UDK 5 Annales, Ser. hist. nat., 13, 2003, 1, pp. 1-134 + 1-51, Koper 2003 ISSN 1408-533X Ai un c NNALEN AnaCi za istrsf(e in mediteransl(e študije Armad di Studi istriani e mediterranei Armais for Istrian and Mediterranean Studies UDK 5 Annales, Ser. hist. nat., 13, 2003, 1, pp. 1-134 + 1-51, Koper 2003 ISSN 1408-533X A NNALE ttnad za istrs/(e in mediteransl(e študije iAnnati di Studi istriani e mediterranei ftnnaCs for 'Istrian and Mediterranean Studies k ISSN 1408-533X 9 . . 9771408533063 UDK 5 ISSN 1408-533X /\ NNALEO Anali za istrske in mediteranske študije Annali di Studi istriani e mediterranei Annals for Istrian and Mediterranean Studies series historia naturalis, 13, 2003, 1 KOPER 2003 ANNALLS • Ser. hist. nat. • 12 • 2002 - 2 Anali za istrske in mediteranske študije - Annali di Studi istriani e mediterranei - Annals for islrtan and Medilerranean Studies ISSN 1408-533X Annales, Ser. hist, nat., 13, 2003, 1 UDK S letnik 13, leto 2003, številka 1 UREDNIŠKI ODBOR/ COM IT AT O DI REDAZIONE/ BOARD OF EDITORS: dr. Roderick M. Baxter (SA), dr. Christian Capape (F), dr. Darko Darovec, dr. Dušan Devetak, dr. Jakov Dulčič (HR), dr. Serena Fonda Umani (IT), dr. Mitja Kaligarič, dr. Andrej Kranjc, dr. Boris KryStufek, dr. Tom Levanič, dr. Lovrenc Lipej, dr. Alenka Malej, dr. Patricija Mozetič, dr. Darko Ogrin, dr. Livio Poldini (IT), dr. Ehud Spanter (IL), dr. Michael Stachowitsch (A), dr. Davorin Tome, Salvator Žltko, dr. Tone Wraber Glavni urednik/Redaftore Capo/Managing Editor: dr. Darko Darovec Odgovorni urednik naravoslovja/ Redattore responsabile per le scienze nabirali/ dr, Lovrenc Lipej Natural Science Editor: U rednica / Redattrice/Editor: Lektor j i/Supervisione/Language editors: P re va ja ki/ Traduttori/Transla tors: Oblikovalec/Progeito grafico/Graphic design: Prelom/Composizione/Typcsctting: dr. Patricija Mozetič Henrik Ciglič (angl./sl.), dr. Michael Stachowitsch (angl.) Henrik Ciglič (angl./sl.), Martina Orlando Bonaca (si./it.) Dušan Podgornik Franc Čuden - Medit d.o.o. 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Redakcija te številke je bila zaključena 10. oktobra 2003 Sotinancirajo/Supporfo finanziario/ Ministrstvo za šolstvo, znanost in šport Republike Slovenije, Financially supported by: Ministrstvo za kulturo Republike Slovenije, Mestna občina Koper, Občina Izola, Občina Piran, Banka Koper ter drugi sponzorji Annales - series historia naturalis izhaja dvakrat letno. Annales - series historia et sociologia izhaja dvakrat letno. Letna naročnina za obe seriji je 7000 SIT, maloprodajna cena tega zvezka je 2500 SIT, Nenaročenih rokopisov in drugega gradiva ne vračamo. Rokopise in naročnino sprejemamo na sedežu uredništva. Rokopise lahko pošiljate tudi članom uredništva. Naklada/Tiratura/Circulation: 700 izvodov Revija Annales series historia naturalis je vključena v naslednje podatkovne baze: BlOSIS-Zoological Record (UK), Aquatic Sciences and Fisheries Abstracts (ASFA). ANNALES • Ser. hist. nat. - 13 • 2003 • 1 Anali za istrske in mediteranske študije - Annafi di Studi istriani e mediterranei - Annals for Istrian and Mediterranean Studies UDK 5 Letnik 13, Koper 2003, številka 1 ISSN 1408-533X VSEBINA / INDICE GENERALE / CONTENTS IHTIOLOGIjA ITTIOLOGIA ICHTHYOLOGY Hakan Kabasakaf Historical and contemporary records of sharks from the Sea of Marmara, Turkey ......................... 1 Starejši in novejši podatki o pojavljanju morskih psov v Marmarskem morju, Turčija Christian Capape, Farid Hemida, Jalti Bensaci, Bechir Safdi & Mohamed Nejmeddine Bradat Records of basking sharks, Cetorhlnus maximus (Gunnerus, 1765) (Chondrichthyes: Cetorhinidae! off the Maghrebin shore {southern Mediterranean): a survey....................................... 13 Pojavljanje morskega psa orjaka, Cetorhinus maximus (Gunnerus, 1756} (Chondrichthyes: Cetorhinidae}, v bližini Maghrebskega obrežja (južno Sredozemlje}: pregled Jakov Duičič, Armin Pailaoro & Sanja Matic On the record of Madeira rockfish Scorpaena madurensis Valenciennes, 1833, in the eastern Adriatic ......................... O vrsti Scorpaena madurensis Valenciennes, ? 833, ujeti v vzhodnem Jadranu 19 MORSKA BIOLOGIJA IN EKOLOGIJA BIOLOG IA ED ECOLOGIA MARINA MARINE BIOLOGY AND ECOLOGY Barbara Sladonja, tvana Maguire, Radovan Erben, Goran Klobučar & Jasna Lajtner Estimating the carrying capacity of coastal areas potentially suitable for mussel culture in the upper Adriatic, Croatia ...................... Ocenjevanje nosilnosti okolja v severnojadranskih obalnih območjih, potencialno primernih za vzgojo školjk Borut Vrišer Meiobenthic fauna (without Harpacticoida) in the southern part of the Gulf of Trieste: List of taxa................................................... Meiobentoška favna (brez harpaktikoidov) južnega dela Tržaškega zaliva: seznam vrst 25 33 Marco Bianchini, Ehud Spanier & Sergio Ragonese Enzymatic variability of Mediterranean Slipper Lobsters Scyllarides latus, from Sicilian waters..... 43 Encimatska variabilnost velikega nagajivca, Scyllarides latus, v sicilijanskih vodah Marco Affronte, Leandro Augusto Stanzani & Giacomo Stanzani First record of the humpback whale, Megaptera novaeangliae (Borowski, 1781), from the Adriatic Sea ........................................... 51 Prvi zapis o kitu grbavcu Megaptera novaeangliae (Borowski, 1781) in the Adriatic Sea KLIMATSKE SPREMEMBE VARIAZIONI CLIMATICHE CLIMATE CHANGES Zatika Črepinšek & Lučka Kajfež-Bogataj Spring phenological trends in Slovenia ................ 57 Trendi pomladanskih fenofaz v Sloveniji Darko Ogrin Suha in mokra leta v submediteranski Sloveniji od 14. do srede 19. stoletja.................................. 65 Dry and wet years in Submediterranean Slovenia fro the 14"' to the mid-19'1' centuries RAZISKAVE SLADKIH VODA RICERCHE Dl ACQUE DOLCI FRESHWATER RESEARCH Janos Nagy & Zoltan Tuba A preliminary report o new type of floating myre from Hungary.............................................. 77 Preliminarno poročilo o novem tipu "zavesastega" barja na Madžarskem Aleksandra Krivograd Klemenčič, Danijel Vrhovšek & Gorazd Kosi ASgae in Dragonja rt ver........................................ 83 Alge v reki Dragonji ANNALES • Ser. hist, nat. • 13 • 2003 • 1 Anali za istrske in mediteranske študije - Annali di Studi istriani e mediterranei - Annals for tstrian and Mediterranean Studies Janja Kogovšek, Sonja Dikovic, Metka Petri č, Josip Rubinič, Martin Knez, Eiza Hrvojič & Tadej Slabe Hydrochemical research of the Mlini springs, Istria ........................................................ 91 Hidrokemične raziskave izvira Mlini, Istra Gregor Muri & Saša Eržen Relations between air temperature, precipitation and surface and vertical water temperature variations in the three Kriško lakes (Julian Alps, NW Slovenia) in July 2002 ................................... 103 Odnos med temperaturo zraka, padavinami ter nihanjem površinske in globinske temperature vode v treh Kriških jezerih (Julijske Alpe, 5Z Slovenija) v juliju 2002 Gregor Kovacič Kraški izviri Bistrice (JZ Slovenija) ........................111 Bistrica karst springs (SW Slovenia) DELO NAŠIH ZAVODOV IN DRUŠTEV ATljVITA DEI NOSTR1ISTITUTI E DELU: NOSTRE SOCIETA ACTIVITIES BY OUR INSTITUTIONS AND ASSOCIATIONS Robert Turk, Vaiter Žiža & Tihomir Makovec Ohranimo želvo v slovenskem morju ..................128 OCENE IN POROČILA RECENSIONI E RELAZIONI REVIEWS AND REPORTS Boris Sket, Matija Gogala, Valika Kuštor (ur.): Živalstvo Slovenije (Davorin Tome).....................126 Andrej GogaSa: Kamen, voda, sonce in veter. Narava Krasa in Slovenske Istre (Mitja Kaligarič) ...........................................127 Ivan Gams: Kras v Sloveniji v prostoru in času (Nataša Režek Donev) ............................. 1 28 Kazalo k slikam na ovitku ....................................130 Index to pictures on the cover..............................1.30 Navodila avtorjem ...............................................131 Instructions to authors.......................................... 133 Slavko Mezek, Bogdan Macarol & Mitja Bricelj Mednarodna delavnica "Ekoremediacije v celostnem upravljanju z vodami v Sredozemlju" .. 123 IHTIOLOGIJA ITTIOLOGIA ICHTHYOLOGY ANNALES • Ser. hist. nat. • 13 - 2003 • 1 original scientific article UDK 597.3(262.4-18) received: 2003-03-01 HISTORICAL AND CONTEMPORARY RECORDS OF SHARKS FROM THE SEA OF MARMARA, TURKEY Hakan KÄBASAKAL Ichthyologies! Research Society, Atatürk Mahallesi, Mente^oglu Caddesi, i'dil apt., No 30, D 4, TR-34764 (Jmraniye, Istanbul E-mail: hakankabasakal@botmai i .corn ABSTRACT Twenty species of sharks, with either confirmed or questionable presence in the Sea of Marmara, comprise nearly the 8% of the total ichthyofauna of Marmaric waters. Regarding their species numbers, squaliform and carcharhini-form sharks, each represented by 7 species, dominated the species composition of sharks in Marmaric waters. Squaliform sharks, scyliorhinid Galeus melastomus, and adult individuals of Hexanchus griseus, have been mostly captured over the deeper parts of shelf and upper slope on the northern side, while Mustelus asterias and M. muste-lus, and scyliorhinids, Scyliorhinus canicula and S. stellaris, as well as the young individuals of H. griseus, and Squatina squatina have been mostly captured in the southern part of Marmara. Alopias vulpinus is the only pelagic species recorded in the present research. The current presence of 5 species, Carcharodon carcharias, Lamna nasus, Galeorhinus galeus, Pnonace glauca and Echinorhinus brucus, is questionable, and for the time being it is not possible to say whether their Mediterranean distribution still extends to Marmaric waters. Southern part of the Sea of Marmara appears a suitable shark nursery, in particular for scyliorhinid and triakid species. Key words: sharks, distribution, shark bycatches, shark nurseries, Sea of Marmara SEGNALAZIÜN! STORICHE E CONTEMPORANEE DI SQUALI NEL MAR Di MARMARA, TURCHIA SINTESI Venti specie di squali, sia che la loro presenza sia confermata o dubbia nel Mar di Marmara, costituiscono quasi I'otto percento dell'ittiofauna totale di tali acque. Perquanto riguarda squali squali form i e carcariniformi, ognuno di essi rappresentato da sette specie, essi dominano la cornposizione di specie di squali in acque marmariche. Squali squaliformi, il boccanera Galeus melastomus, e iridividui aduki dello squalo capopiatto Hexanchus griseus, sono stati catturati principalmente nel le parti piit profonde del piano e del pendió superiore nella parte settentrionale, mentre Mustelus asterias e M. mustelus, gli sciliorinidi Scyliorhinus canicula e S. stellaris, giovani individui di H. griseus, nonché Squatina squatina, sono stati catturati principalmente nella parte meridionale di Marmara. Alopias vulpinus é fuñica specie pelágica riscontraia nella presente ricerca. La presenza di 5 specie, Carcharodon carcharias, Lamna nasus, Galeorhinus galeus, Prionace glauca e Echinorhinus brucus, risulta dubbia, pertanto non é per iI momento possibile ipotizzare un ampliamento delh loro distribuzione mediterránea anche al Mar di Marmara. La parte meridionale del Mar di Marmara appare Idónea alia funzione di nursery, soprattutto per sciliorinidi e triachidi. Parole chiave: squali, distribuzione, catture di squali, nursery per squali, Mar di Marmara 1 ANNAtES • Ser. hist. nat. • 13 • 20Ü.3 • 1 Hilfcan KAFiASAKAL: HISTORICA!. AND CONTHMPORARY RECOROS OF 5HAKKS ROM THE SEA OF MARMARA, TURKEYJ-12 INTRODUCTION Although the origin of the ichthyological studies in the Sea of Marmara dates back to nearly a century {see Bilecenoglu ef at., 2002, for review), very few specific studies on sharks of this unique inland sea have been produced to date. Our knowledge about sharks of the Sea of Marmara is limited to the general ichthyological works (Ninni, 1923 [in Biiecenoglu et a!., 2002]; De-vedjian, 1926; Ayash, 1937; Erazi, 1942; Aksiray, 1987; Bauchot, 1987; Kocatas eta/., 1993; Merit;, 1995; Mater & Merle, 1996), or to a few specific studies on sharks of this sea (Benli et at., 1993; Oku§ et at., 1996; Uysal et at., 1996; Kabasakal, 1998). According to the most recent list of elasmobranch species of the seas of Turkey, 15 confirmed and one questionable species of sharks are present in the Sea of Marmara (Kabasakal, 2002), while the presence of another 4 species of sharks, Galeoihinus galeus, Prionace glauca, (ichinorhinus brucus and Squatina oculata, from Marmaric waters have also been reported in some pioneering works and in a single recent ichthyological work dealing with Turkish seas (Ninni, 1923 [Biiecenoglu ef a!., 2002]; Devedjian, 1926; Ayajli, 1937; Merit, 1994 [in Bile-cenoglu ef al., 2002}). With the exception of S. oculata, whose presence was described in a recent report (Meric, 1994 [Bilecenoglu ef at., 20021), the status of the remaining 3 species, G. galeus, P. glauca and E. bnicus, is uncertain and regarding their presence in the Sea of Marmara (Ninni, 1923 [Bilecenogfu et a!., 20021; Devedjian, 1926; Ayash, 1937), it would be proper to consider them as "doubtful species". The main objective of the present work is to provide information on the basis of a number of historical and contemporary shark records from the Sea of Marmara, and to update the species iist with the addition of new data. MATERIAL AND METHODS The area encompassed by the present research is a subunit of the Mediterranean Sea and known as the Sea of Marmara (Fig. 1). It is connected with the Mediterranean Sea via the Dardanelles and with the Black Sea «pine— PasaUmaiu Vg^): 28" 29" .w Fig. 1: Map of the study area; circled numbers indicate the sampling locations; -k indicates the stranding site of Carcharodon carcharías in the Bosphorus Strait in February 1881. Si. 1: Zemljevid preučevanega območja; obkrožene številke označujejo posamezna vzorčišča; -k ponazarja mesto v Bosporski ožini, kjer je februarja 1881 nasedel beli morski volk Carcharodon carcharías. ANNALES • Ser. hist. nat. • 13 • 2003 • 1 Hakim KA8ASAXAL: H1STORICAI AND CONTEMPORARY RECORDS Of SHARKS FROM THE SEA OF MARMARA, TURKEY, 1-12 through the Bosporus Strait. While Marmara's surface waters are affected by the Black Sea, its deeper layers remain under the influence of the Mediterranean (Ko-cataf et a/., 1993). According to Oztiirk & Oztiirk (1996), the Sea of Marmara is an ecological barrier, a transition zone or an acclimatisation area, influencing the dispersal of species between the Mediterranean and Black Seas. An extensive field survey was carried out between 1991 and 1999 along the coast of Sea of Marmara (Fig. 1) to collect or examine sharks. Whenever possible, the author joined fishermen (mostly purse-seiners, gill-netters and bottom long-liners) to collect shark samples. Sharks delivered to the Istanbul Fish Market were also analysed for the purpose of this research. Furthermore, the available ichthyological literature on the Sea of Marmara was critically reviewed. The following data were recorded for each species: total length (TOT) in cm, sex of the animal, date and location of the capture. Total length of the specimens was measured with the caudal fin in the depressed position. Whenever possible, teeth and skin samples were also collected, now kept in the author's personal collection. Capture locations of the examined specimens, as well as those of recent records are shown in circled numbers in figure 1. Dashed lines in figure 1 indicate northern and southern borders of the by catch area of C. carcharias, L. nasus, A. vul-pinus and P. gtauca, reported by Devedjian (1926), Ayajli (1937), Guney (1974), Uner (1984) and Akjiray (1987) from the Sea of Marmara. For an easier understanding, status of occurrence of sharks recorded from the Sea of Marmara was classified under the following categories: (A) species examined in the present study; and (B) species cited by other researchers but not examined in the present study. Status of occurrence of each species is denoted in parentheses after its scientific name. The absence of a species in the recent catch records or in the recent general ichthyological lists, concerning exclusively the fish fauna of the Sea of Marmara, at least for the last 25 years, was used as the criteria for considering the species as "questionable". Identification of the species follows Whitehead et a\. (1984) and Compagno (1984a, b). Taxonomic nomenclature follows European Register of Marine Species, Chondricthyes brief checklist (http://erms.biol.soton. ac.uk/lists/). All photographs (fig 2-9) were taken by the author. RESULTS AND DISCUSSION Field surveys and review of the available literature have revealed the presence, either confirmed or questionable, of 20 shark species, representing 11 families in the Sea of Marmara. Relevant details about these species are given below. Order Hexanchiformes Family Hexanchidae 1. Hexancbus griseus (Bonnaterre, 1788) (A) Previous recordings: Ninni (1923, [Bilecenoglu eta/., 2002]), Devedjian (1926, as Notidanus griseus), Oner (1984), Meric. (1995), Kabasakai (1998, 2002). Material examined: 1 t? (TOT 250 cm) captured on February 20, 1997, off the coast of §arkoy (40°09'50" N, 27°18'40" E) at a depth of 50 m (Kabasakai, 1998) (Fig. 1, stat. 1); 1 Í? (TOT 125 cm), captured in March 1997 off the coast of ijarkoy (same location as the previous specimen, Fig. 1, st. 1); 2 ? (TOT 380 and 450 cm, respectively) captured off the coast of Tuzla, at a depth of 200 m (Fig. 1, st. 2), second specimen is shown in figure 2; 1 9. (TOT 420 cm) captured in December 1999 off the coast of Yasstada at a depth of 220 m (Fig. 1, st. 3). According to Oner (1984), bluntnose sixgill shark is one of the common and largest sharks of the Sea of Marmara. Merit; (1995) recorded this species from the catches at depths between 120 to 350 m by gill-netting over the northern continental slope, describing it as a rare bycatch by demersal fishing gear. Order Lamniformes Family Lamnidae 2. Carcbarodon carcharias (Linnaeus, 1758) (B) Previous recordings: Devedjian (1926, as Carel ¡aro-don Rondeletii), Güney (1974), Oner (1984), Akjiray (1987), Fergusson (1996), Bilecenoglu etal. (2002). Devedjian (1926) reported on a great white shark (TOT 400 cm) captured in the Sea of Marmara, and added that its stomach content included a number of bonitos. According to Güney (1974) and Oner (1984), C. carcharías is present in the Sea of Marmara in all seasons and it approaches Marmaric entrance of the Bosporus Strait especially in winter. One of the common points stated by these three authors was that the great white shark was usually a common bycatch by tuna handliners in the Sea of Marmara, and this one was captured incidentally as a result of chasing schools of tunas and bonitos. Liner (1984) also reported that most of the great white shark captures were made between December and late March, and that most of the individuals were captured around the Prince Islands (Fig. 1) and near the Bosporus Strait. According to Ak^tray (1987), C carcharias inhabits the Sea of Marmara and rarely occurs near the Pontic entrance of the Bosporus Strait. Fergusson (1996) reported the capture of three individuals of C. carcharias in the Sea of Marmara. These are: one stranded individual (TOT 391 cm) near Beyler- ANNALES • Ser. hist na t. ■ 13 ■ 2003 • 1 Hakim KABASAKAL: HiSTORICAl. AND CONTEMPORARY RECORDS OF SHARKS FROM THE SEA OF MARMARA, TURKEY,!. 12 beyi coast (Bosporus Strait) in February 1881 {* in Fig. 1); 1 2 (TOT 470 cm, W 1500 kg), captured on November 17, 1881; and 1 $ (TOT 500+ cm, W 3750 kg), captured in February 1962. Fergusson (1996) stated that the weight of the last individual was no doubt an error. No contemporary record of C carcharías is available, and no individual of this species was captured or even sighted during the field surveys. Although the presence of C. carcharías in the 5ea of Marmara has been reported by Bilecenoglu ef al. (2002) in the Checklist of the marine fishes of Turkey, the information given herewith is probably based on previous recordings. Therefore, its current presence in Marmaric waters is "questionable" and requires confirmation. 3. Lamria nasus (Bonnaterre, 1788) (B) Previous recordings: Ninni (1923, [Bilecenoglu elal., 2002]), Devedjian (1926, as Lamna cornubica), Güney (1974), Üner (1984), Ak§iray (1987), Bauchot (1987), Mater & Meri^ (1996), Bilecenoglu et al. (2002), Kaba-sakal (2002). Although no capture information on L nasus individuals is available, porbeagle is, according to Devedjian (1926), Güney (1974), (Jner (1984) and Aksiray (1987), yet another common lamnoid shark of the Sea of Marmara, with most of its captures made around the Prince islands and near the Marmaric entrance to the Bosporus Strait (Fig. 1). Güney (1974) and Üner (1984) also reported that, as for C. carcharlas, bycatches of L. nasus by tuna fishing gear occurred mostly in the winter, as a result of chasing schools of tunas and bonitos. The recording of L. nasus by Kabasakai (2002) from the Sea of Marmara is based on previous recordings of this species by other researchers. Although the presence of L. nasus in the Sea of Marmara has been reported by Bilecenoglu et al. (2002), the information given herewith is probably based on previous recordings. No individual of this species was captured or even sighted during the field surveys. Therefore, its current presence in Marmaric waters is "questionable" and requires confirmation. Family Alopiidae 4. Alopias vulpinus (Bonnaterre, 1788) (A) Previous recordings: Ninni (1923, [Bilecenoglu et al., 2002]), Devedjian (1926, as Alopias vulpes), Erazi (1942, as Alopias vulpes), Uner (1984), Kocataj et al. (1993), Kabasakai (2002). Material examined: 1 <3 (TOT 190 cm) captured on April 12, 1997, off the coast of Silivri (Fig. 1, st. 4). Devedjian (1926) reported on some enormous A. vulpinus individuals ending at the Istanbul Fish Market, without giving information on their size or biology. Its presence in the Sea of Marmara was possibly the result of chasing the pelagic fish schools. As A. vulpinus is a highly migratory shark (Compagno, 1984a), it is necessary to investigate its movements in detail to figure out whether its presence in the Sea of Marmara is regular or just incidental. Despite this uncertainty, A. vulpinus is the only confirmed pelagic shark species recorded in Marmaric waters during the present research. Fig. 2: Hexanchus griseus (Bonnaterre, 1788} ($, TOT 450 cm) displayed at a fish market in Istanbul. SI. 2: Hexanchus griseus (Bonnaterre, 1788) ($, TOT 450 cm), postavljen na ogled na istanbulski ribji tržnici. 4 ANNALES ■ Ser. hist nat. • 13 • 2003 • 1 Hakim KABASAKAI: HtSTORlCAl AND CONTf Mf'ORARY RECORDS OF SHARKS FROM THE SEA Of MARMARA, TURKEY, 1-12 -sbssv-- Fig. 3/SI. 3: Calf lis meiastomus Rafmesque, 1810 (i, TOT 22 cm). Fig. 4/Sl, 4: Scyliorhinus canicula (Linnaeus, 1758) (, TOT 125 cm). 6 ANNALES • Ser. hist. nat. • 12 ■ 2002 ■ 2 h il kan kabasakal: h'storiou and contemporary records of sharks erom the sea of marmara, turkey, 1-12 Fig. 7/Sl. 7: Oxynolus centrina (Linnaeus, 1758) (2, TOT 40 cm). Family Carcharhinidae Order Squaliformes 11. Príonace glauca (Linnaeus, 1758) (S) Previous recordings: Ninni (1923, [Bilecenoglu eta/., 2002]), Devedjian (1926, as Carcharías glaucus), Ayasli (1937, as Carcharías glaucus), Güney (1974), Oner (1984), Bilecenoglu et al. (2002). Record of an enormous blue shark (TOT 800 cm) delivered to the Istanbul Pish Market (Ayajli, 1937). The author stated that the stomach content of this individual included remains of tuna fish and dolphin. However, regarding the maximum confirmed size (383 cm) of the blue shark and the unconfirmed reports on larger 480 to 650 cm long individuals (Compagno, 1984b), the size of this individual reported by Ayasli (1937) seems "unreasonable". Furthermore, we could hypothesize that by considering the size (TOT 800 cm) and stomach contents (tuna fish and dolphin), Príonace glauca reported by Aya$li (1937) was actually a Carcharodon carcharías. No photographs or parts of this individual have been preserved. Güney (1974) and Üner (1984) reported that, as far as lamnoid sharks are concerned, bycatches of P. glauca in tuna fishing gear mostly occurred around the Prince Islands and near the Marmaric entrance to the Bosporus Strait. No individual of P. glauca was captured or even sighted during the field surveys, and no contemporary record of this shark from this sea is available. Although the presence of P. glauca in the Sea of Marmara has been reported by Bilecenoglu et al. (2002), the information given herewith is probably based on previous recordings, its current presence in the Sea of Marmara seems "questionable" and requires confirmation. Family Dalatiidae 12. Oxynotus centrina (Linnaeus, 1758) (A) Previous recordings: Erazi (1942, as Squalus centrina), Mater & Meriç (1996), Kabasakal (2002). Material examined: 1 9 0'OT 40 cm, Fig. 7) captured in November 1994 off the northern coast of Yassiada at a depth of 90 m (Fig. 1, st. 11); 2 3 (TOT 35 to 41 cm, respectively) captured in February 1996 off the western coast of Ekinlik Island at a depth of 60 m (Fig. 1, st. 12). O. centrina is a rare bycatch by bottom set gill-nets and long-lines in the Sea of Marmara. 13. Dalatias licha (Bonnaterre, 1788) (8) Previous recordings: Meriç (1995), Kabasakal (2002). Meriç (1995) reported on a single male (TOT 34.5 cm) captured on July 5, 1991, off the coast of Buyukçekmece (Fig. 1, St. 13) at a depth of 270 m. No D. licha individual was captured during the field surveys. It is very rare in the Sea of Marmara, and no information is available on its distribution in the Sea of Marmara. Family Centrophoridae 14. Centrophorus granulosus (Bloch & Schneider, 1801) (B) Previous recordings: Benli et al. (1993), Meriç (1995), Mater& Meriç (1996), Kabasakal (2002), 7 ANNALES • Ser, hist. nat. • 13 • 2003 ■ 1 Hakan KABASAKAL: HISTORICAL AND CONTEMPORARY RECORDS Of SHARKS FROM THE SEA OF MARMARA, TURKEY, 1-12 C granulosus has been recorded for the first time in the Sea of Marmara by Benli et al. (1993); the record is based on 5 specimens captured in the autumn of 1992 at a depth of 400 m (40°36'0S!! N, 28c,36'03" 6) (Fig. 1, St. 14). Merig (1995) reported that gulper sharks were rarely captured by bottom set gill-nets between depths of 120 to 350 m over the northern continental slope of the Sea of Marmara. No individual of C. granulosus was captured during the field surveys. It is very rare in the Sea of Marmara, and no information is available on its distribution in the Sea of Marmara. 15. Centrophorus uyato (Rafinesque, 1810) (B) Previous recordings: Meriç (1995), Kabasakal (2002). Meriç (1995) reported on a female (TOT 44.2 cm) captured on May 19, 1989, off the coast of Yejilkoy (Fig. 1, st. 15) at a depth of 150 m and on a male (TOT 45.3 cm) captured on August 11, 1991, off the coast of Buyukçekmece (Fig. 1, st. 13) at a depth of 270 m. No individual of C uyato was captured during the field surveys. It is very rare in the Sea of Marmara, and no information is available on its' Marmaric distribution. Fig. 8/SI. 8: Squabs acanthias Linnaeus, 1758 0, TOT 45 cm). Fig. 9/St. 9:Squatina squatina (Linnaeus, 1758) (9, TOT 87 cm). Family Squalidae 16. Squabs acanthias Linnaeus, 1758 (A) Previous recordings: Ninni (1923, IBilecenoglu et al., 2002]), Devedjian (1926, as Acanthias vulgaris), Erazi (1942), Bauchot (1987), Meriç (1995), Mater & Meriç (1996), Kabasakal (2002). Material examined: 1 6000 1000 5 Pelagic trawl Ras Tonkourft eastern Algeria 18/05/2000 unpubl. data 19 Female ? ? 5 Pelagic trawl Ras loukoLicIl eastern Algeria 18/05/2000 unpubl, data 20 Male 4250 ? '{ Purse seine Gabfes Gulf southern Tunisia 24/04/2001 21 Male >7000 1500 ? Pelagic trawl Off Annaba eastern Algeria 28/03/2002 unpubl. data Tab. 2: Body measurements made on two Cetorhinus maximus caught off the Algerian coast. Tab. 2: Telesne mere dveh morskih psov orjakov Cetorhinus maximus, ujetih v tunizijskih obrežnih vodah. produces off the Maghrébin shore or whether if onfy feeds in the area. However, as captures of basking sharks increased during the last ten years, both feeding and reproducing cannot be excluded in the area but need further observations. Nevertheless, the belief that the Mediterranean Sea can be considered a potential reproductive area has been given a boost by records of the second Mediterranean filter feeding species, the devil ray Mobula mobuiar reported by Capapi & Zaouaii (1976), Brada'i & Capape (2001) and Hem Ida ef al. (2002a), Moreover, the ray is even considered a Mediterranean endemic species (No-tarbartolo di Sciarra & Bianchi, 1998). In this area, these two species probably found sufficient resources to reproduce as well as to develop, just as other pelagic teleost fishes (Kartas, 1981; Chavance ef a!., 1986; Bradai, 2000). Fig. 3: Fiead of a male shark caught off Annaba, Algerian coast (for details see record 21 in Table 1). (Photo: F. Hemida) SI. 3: Glava samca, ujetega v bližini Annabe ob alžirski obali (o podrobnostih glej zapis št. 21 v tabeli 1). (Foto: F. Hemida) Measurements (mm) Record 16 Record 17 Total length 4900 3300 Snout to first dorsal fin 2020 1700 Snout to second dorsal fin 3600 222.0 First dorsal height 520 350 Second dorsal height 150 100 Pectoral fin length 620 510 Pelvic fin length 390 260 Caudal fin length 1050 770 Snout to nostril 90 60 Mouth width 680 430 Internostril space 140 90 Snout to mouth 310 185 Clasper length 390 - 16 ANNALES • Ser. hist. nat. • 13 • 2003 ■ 1 Chris! ¡an CAPAPE crai.: RECORDS OF BASKfNC 5HARKS. Cl TORHMV5 MA.WMUS {CUNNERIJS, 1765) (C H ON DR IC H T H Y ES"c ET O R H SN i DAE) ...., 13-¡a"'-' POJAVLJANJE MORSKEGA PSA ORJAKA, CETORHINUS MAXIMUS (GUNNERUS,1756) (CHONDRICHTHYES: CETORHINIDAE), V BLiŽiNI MAGHREBSKEGA OBREŽJA (JUŽNO SREDOZEMLJE): PREGLED Christian CAPAPÉ Laboratoire d'Ichtyologie, Université Montpellier SI, Sciences et Techniques du Languedoc, F-34 095 Montpellier cedex 05 E-mail: tapape@univ-montp2,fr Farid HEMtDA & jalil BENSACI Laboratoire Halieutique, Institut des Sciences de la Nature, Université des Sciences et Techniques Houari Boumediertne, 16111 Bab Ezzouar, Alger, S. P. 32, El Alia, Algérie Béchir SAÏDI & Mohamed Nejmeddine 8RADAÏ Institut National des Sciences et Technologies de la Mer, Centre de Sfax, 3018 Sfax, B. P. 1035, Tunisie POVZETEK V pričujočem prispevku avtorji navajajo stare/še in novejše podatke o ujetju morskih psov orjakov Cetorhinus maximus v bližini Maghrebskega obrežja (v alžirskih in tunizijskih vodah} in jih primerjajo s podatki o pojavljanju populacije teh morskih psov v drugih delih Sredozemskega morja. Ključne besede: Chondrichthyes, Cetorhinidae, Cetorhinus maximus, Maghrebsko obrežje, Alžirija, Tunizija, Sredozemsko morje REFERENCES Barrufl, j & i. Mate (1996): Registros de tiburón peregrino (Cetorhinus maximus) en aguas del Mediterráneo. Bol. Asoe. Bp. Elasmo., 2, 37-52. Barrut,}. & I. Mate (2002): Tiburones del Mediterráneo. El liiores del Set-ci fendes, Arenys del Mar, 292 pp. Bradai, M. N. (2000): Diversité du peuplement ichtyque et contribution à la connaissance des sparidés du golfe de Gabes. Ph.D. Thesis. University of Sfax, Tunisia, 600 pp. Bradai, M. N. & C. Capapé (2001): Captures du diable de mer, Mobula mobular dans le golfe de Gabès (Tunisie méridionale, Méditerranée centrale). Cybiurn, 25 (4), 389-391, Bradai, M. N. & M. Ghorbel (1992): Capture d'un requin pèlerin Cetorhinus maximus (Gunnerus, 1765) dans la région du golfe de Gabès, Tunisie. Bull. Inst. natn sci. tech. Océanogr; Pêche, Salammbô, 3,10-15. Capapé, C. (1975): Sélaciens nouveaux et rares le long des côtes tunisiennes. Premières observations biologiques. Arch. Inst. Pasteur, 51(1-2), 107-128. Capapé, C. (1984): Nouvelles données sur la morphologie et la biologie de la reproduction de Carcharhinus plumbeus (Nardo, 1827) (Pisces, Carcharhinidae) des côtes tunisiennes. Inv. Pesq., 48S2), 115-137. Capapé, C, (1987): Propos sur les Sélaciens des côtes tunisiennes. Bull. Inst. natn sci. tech. Océanogr; Pêche, Salammbô, 14, 15-32. Capapé, C. (1989): Les Sélaciens des côtes méditerranéennes: aspects généraux de leur écologie et exemples de peuplements. Océanis, 1S (3), 309-331. Capapé, C., A. Cbadii & R. Prieto (1975): Les Sélaciens dangereux des côtes tunisiennes. Arch. Inst. Pasteur, 53(1-2), 61-108. Capapé, C. & }. Zaouali (1976): Note sur la présence de la Mante de mer Mobula mobular (Bonnaterre, 1788) (Sélaciens, Rajiformes) dans les eaux tunisiennes. Dori-ana, 5(223), 1-8. Chakroun, F. (1966): Capture d'animaux rares en Tunisie. Bull. Inst. natn sci. tech. Océanogr; Pêche, Salammbô, 1(2), 75-79. Collenot, G. (1969): Etude biométrique de la croissance relative des ptérygopodes chez la petite roussette Scylio-rhinus canicula L. Cah. Biol. Mar., 10, 309-323. Compagno, L. V.}. (1984): FAO species catalogue. Vol. 4, Sharks of the world. An anrtotated and illustrated catalogue of shark species known to date. Part 1: Hex-anchiformes to Lamniformes. FAO Fish. Synop., 125 (4), 1-249. Cbavance, P., F. Chabane, F. Hemida , H. Korichi, M. P. Sanchez, }. L. Bouchereau, j. A. Tomasini & F. Djabali (1986): Evaluation du rendement par recrue relatif à partir de fréquences de taille: application à quelques stocks d'anchois, de sardinelles et de chinchards de la Méditerranée occidentale. CGPM, FAO Rapp. Pêches, (347): 186-204. 17 ANNALES • Ser. hist. nat. • 13 • 2003 • 1 CUmUao CAPAPÉ a ¡¡I.: RECORDS Of BASKING SHARKS, CLTORHINUS MAXIMUS {GUNNERUS, 1765) (CHONORICHTI1YES: CFTORHINiDAt) .... 13-18 Dieuzeide, R., M. Novella & ). Roland (1953): Catalogue des Poissons des côtes algériennes. Bull. Stn. Aquic. Pêch. Castiglione (n.s.), 4, 1-135. Golani, D. (1996): The marine ichthyofauna of the Eastern Levant. History, inventory and characterization. Israel j. Zool.,42, 15-55. Hemida, F. (1998): The shark and skate fishery in the Algerian basin: biological and technological aspect. Shark News, 12, p. 14. Hemida, F. & N. Labidi (2001): Nouvelle liste commentée des requins de la côte algérienne. Rapp. Comm. int. Mer Médit., 36, p. 273. Hemida, F. & C. Capapé (2002): Observations on a female Bramble shark, Echinorhinus brucus (Bonnaterre, 1788) (Chondrichlhyes: Echinorhinidae), caught off the Algerian coast (southern Mediterranean). Acta Adriat, 43(1), 103-108. Hemida, F., S. Mehezem & C. Capapé (2002a): Captures of the giant devil ray, Mobula mobular Bonnaterre, 1788 (Chondrichthyes: Mobulidae) off the Algerian coast (southern Mediterranean). Acta Adriat., 43(2), 69-76. Hemida, F., R. Seridji, N. Labidi, J. Bensaci & C. Capapé (2002b): New data on Carcharhinus spp. (Chondrichthyes: Carcharhinidae) from off the Algerian coast (southern Mediterranean). Acta Adriat., 43(2), 83-93. Hemida, F. & C. Capapé (2003): Observations on blue sharks, Prionace glauca (I., 1758) (Chondrichthyes: Carcharhinidae), from the Algerian coast (southern Mediterranean). ]. Mar. Biol. Ass.' U. K., 83(4), 873-874. Bureau, j. C. & T. Monod (eds.) (1973): Check list of the fishes of the north-eastern Atlantic and of the Mediterranean (CLOFNAM). Vol. 11. Bibliography. UNESCO, Paris. Kabasakal, H. (2002): Capture of a female basking shark, Cetorhinus maximus (Gunnerus, 1765), from southern Turkey. Annales Ser. hist, nat,, 12(1), 31-32. Kartas, F. (1981): Les Clupéidés de Tunisie. Caractéristiques biométriques et biologiques. Etude comparée des populations de l'Atlantique et de la Méditerranée. Ph.D. Thesis, University of Tunis, Tunisia, 608 pp. Lipej, L., M. Makovec, M. Orlando & V. Ziza (2000): Occurrence of the basking shark, Cetorhinus maximus (Gunnerus, 1765), in the waters off Piran (Gulf of Trieste, Northern Adriatic). Annales Ser. hist, nat, 10(2), 211-216. Najaï S. (1980): Note sur la présence de deux requins pèlerins dans le golfe de Tunis. Bull. Inst, natn sci. tech. Océanogr; Pêche, Salammbô, 7, 151-152. Notabartoio di Sciara, G. & I. Bianchi (1998): Guida degli squali e del le razze del Mediterráneo. F. Muzzio Ed., Padova. Quignard, J. P. & C. Capapé (1971): Liste commentée des Sélaciens de Tunisie. Bull. inst. natn sci. tech. Océanogr; Pêche, Salammbô, 2(2), 131-141. Quignard, J. P. & C. Capapé (1972). Complément à la liste commentée des Sélaciens de Tunisie. Bull. Inst. natn sci. tech. Océanogr; Pêche, Salammbô, 2(3), 445-447. Raïs, C. & F. Baccar (1998): Compte-rendu de la visite effectuée pour examiner un requin de grande taille capturé à Ghar-El-Melh. Rapp, CAR/ASP, 1 p. Serena F., M. Vaccht & G. Notarbartolo dt Sciarra (2000): Geographical distribution and biological information on the basking shark, Cetorhinus maximus in the Tyrrhenian and Ligurian seas. Proc. 3rd Europ. Elasm. Assoc. Meet., Boulogne-sur-Mer, 1999. Séret, B & J. Y. Sire (eds.), Soc. Fr. Ichtyol. & IRD, Paris, p. 47-56, Soldo, A. & I. jardas (2002): Large sharks in the eastern Adriatic. Proc. 4th Europ. Assoc. Meet., IJvorno (Italy), 2000. Vacchi, M., G. La Mesa, f". Serena & B. Séret (eds.) ICRAM, ARPAT & SFI, Paris, p. 147-155. 18 ANNALES • Ser. hist. nat. • 13 • 2003 • 1 original scientific article UDK 597.5(262.3-12) received: 2003-07-10 ON THE RECORD OF MADEIRA ROCKFISH SCORPAENA MADURENSIS VALENCIENNES, 1833, IN THE EASTERN ADRIATIC Jakov DUL ČIČ, Armin PAL LA ORO & Sanja MATIC institute of Oceanography and Fisheries, HR-2'1000 Split, P.O.BOX 500 E-mail: dulcic@izor.hr ABSTRACT A Madeira rock fish, Scorpaena madurensis Valenciennes, Í833, was caught: near the island ofOaksa (Dubrovnik) in March 2003. As far as the Madeira rock fish is concerned, this is, to our best knowledge, second record of this species for the eastern Adriatic. The presented morphometric and meristic data are the first for this species from the eastern Adriatic, Key words: Scorpaena madurensis, second record, eastern Adriatic TESTIMON1ANZA DS SCORFANOTTO D1 MADEIRA SCORPAENA MADURENSIS VALENCIENNES, 1833 IN ADRIATICO ORIENTALE SINTESI Un esemplare di scorfanotto di Madeira, 5corpaena madurensis Valenciennes, 1833, é stato catturato vicino al-l'isola di Daksa (Ragusa) nel marzo del 2003. Secondo le conoscenze degli autori, si tratta della seconda testimoni-anza della presenza dello scorfanotto di Madeira nell'Adriatico orientate. E'arlicolo riporta i primi dati morfometrici e meristici per questa specie in Adriático orientals. Parole chiave: Scorpaena madurensis, Adriático orientaie, seconda segnalazione 19 ANNALES - Ser. hist. nat. • 13 ■ 2003 ■ 1 lakov PUlČfČeia/.rON THE RECORD OE MADEIRA ROCKFISH SCORPAENA MADURENSIS VALENCIENNES, 1833. IN THE EASTERN ADRIATIC, S9-22 INTRODUCTION MATERIAL AND METHODS Some 430 fish species and subspecies (Cyclostoinata not included) have been observed in the Adriatic Sea (Lipej & Dulcic, in press), and this number can be so far regarded as correct and complete for several reasons. Of this number, the very rare and rare fishes make up almost a quarter (24.2%). The Madeira rockfish Scorpaena madurensis belongs to the very rare species in the Adriatic Sea (Jardas, 1985, 1996), It is a small demersal fish found in shallow coastal waters at depths ranging from 20 to 40 m (Schneider, 1990), It occurs in the eastern Atlantic (Azores, Madeira, and Morocco to the Canaries, Cape Verde and Senegal) and at several localities in the Mediterranean Sea (Schneider, 1990). The records on biology and ecology of this species in the areas of distribution and in the Adriatic Sea are scarce in the literature. Hureau & Litvinenko (1986) noted that the Madeira rockfish feeds on crustaceans and small fishes. Vacchi ef a/. (1999) presented data about the occurrence and habitat of juveniles and adults at Ustica Island (Mediterranean Sea), while Morato etal. (2001) reported the parameters of length-weight relationship of this species for the Azores archipelago. There are no data for the Adriatic Sea, except the notation of the first record for the eastern Adriatic (Kolombatovic, 1904). The main goal of this paper is to present first data on morphometric and meristic characteristics of this species and to register its second record for the eastern Adriatic. The Madeira rockfish was caught on March 15Ih 2003 near the island of Daksa (near Dubrovnik) (Fig. 1) by trammel bottom net (mesh size 28 mm) at a depth of 24 m (on the littoral rocky bottom). The specimen (juvenile stage, female) (Fig. 2) was identified according to jardas (1996). It is deposited and registered in the Ich-thyoiogical Collection of the Institute of Oceanography and Fisheries in Split, Croatia. The specimen was preserved in 4% buffered formaldehyde immediately after capture, subsequently measured to nearest 0.01 mm, and weighed to the nearest 0.01 g. Meristic characteristics considered were: dorsal, anal, pectoral, ventral and caudal fins. RESULTS AND DISCUSSION The record of the Madeira rockfish near Daksa Island (Dubrovnik) is the second record of this species in the eastern Adriatic. Kolombatovic (1904) recorded 5. madurensis (he identified the specimen as Sebastes maderensis Lowe) (total length TL - 130 mm) for the first time on August 3rti near the island of Lastovo (open Central Adriatic) in 1902. The same author mentioned that some specimens had already been found near Malaga (Spain), Beirut (Lebanon) and along the coast of Syria. S. madurensis is a poorly known species distributed on the littoral rocky bottoms of some areas of the Mediterranean Sea, such as southeastern Spain, Sicily, Daksa 42°20'N Grebeni _ Fig. 1: Scorpaena madurensis. Geographic location of the record in the South Adriatic area (SW-S Daksa Islet). Si 1: Lokacija v Jadranu, kjer je bila ujeta Scorpaena madurensis OZ-} otoček Daksa). 20 ANNALLS • Ser. hist. nat. • 13 • 2003 • 1 lakov DULČC at al.: ON THE RECORD Of MADEIRA ROCKffSH SCORPAENA MADURENSIS VAIENCISNNES, IB33, IN THE EASTERN ADRIATIC, ¡9-22 Greece (Ionian and South Aegean) and Lebanon (Tor-(onese, 1975; Kaspirts, 1976; Economidis & Daoulas, 1981; Lanfranco, 1993). Hureau & Litvinenko (1986) referred to several localities in the Mediterranean where the Madeira rockfish occurs: southeastern coast of Spain, Strait of Messina, Syracuse and coast of Lebanon. It is very interesting that they excluded the Adriatic Sea as its distribution area. Tab. 1: Sc.orpaena madurensis. Morphomctric (in cm) and meristic data (Daksa Island, Dubrovnik, March 2003). Tab. 1: Scorpaena madurensis. Morfometricni (v cm) in meristicni podatki (otocek Daksa, Dubrovnik, marec 2003). Measurements (cm) 9 juv. Total length (TL) 11.31 Standard length (SL) 8.72 Head length (HI.) 3.71 jOrbital diameter (O) 0.91 jinterorbitai width (IO) 0.43 iPreorbital length (PRO!J 0.85 Jpostorbital length (POOL) 1.95 ¡Predorsa! distance (PDD) 2.55 Preventral distance (PVD) 3.75 Preanal distance (PAD) 6.49 Prepectora! distance (PPD) 3.07 |Dorsal fin length (DL) 5.16 ¡Anal fin length (AL) 1.04 Ventral fin length (VL) 2.71 [Pectoral fin length (PL) 2.51 Caudal fin length (CL) 2.56 3.03 Maximum height (Hmax) Caudal peduncul height (Hmini 0.89 Dorsal ray (D) Xt/10 Anal ray (A) ill/5 Pectoral ray (P) 15 Ventral ray (V) I/5 Caudal ray (Q 11-11-11 In Table 1, the main morphometric and meristic data are presented and are the first for this species from the Adriatic Sea. They are in agreement with those presented by Hureau & Litvinenko (1986) and Jardas (1996). Kolombatovič (1904) reported the length of 130 mm of the caught Madeira rockfish at the Lastovo Island, and this has been, until now, the only reported length of this species caught in the eastern Adriatic. Bini (1968) pointed that this species attains a maximum size of 14 cm, while Morato ei ai. (2001) gave length range for the specimens caught at the Azores from 5.4 to 17.8 cm (mates: from 8.4 to 17. cm; females: from 6.9 to 15.6 cm). The specimen caught near Daksa was caught on the littoral rocky bottom together with photophilic algae, which is very much in line with the findings of Vacchi et ai. (1999). They observed specimens on hard substrate, both on rocky bottoms with photophilic algae, rich in crevices and with different slope, and, to a lesser extent, on hard bottom with pebbles characterised by gentle slope (Ustica Island, Northern coast of Sicily). Moreover, they also found that both young and adults seemed to require the same habitat features. Riera ei al. (1995) reported that littoral crevices and cavities along the shallow waters (0.8-15 m depth) represent the preferred habitat of this species. As for the bottom slope, it does not seem to affect the distribution of specimens and, in terms of ecological requirements, no difference between young and adults has been found (Riera et ai., 1995). Bini (1968) considered it preferentially inhabits the rocky coasts of the islands between 20 and 40 m depth. Fig. 2/51. 2: Scorpaena madurensis Valenciennes, 1833. (Photo/Foto: A. Paflaoro). 21 ANNALES • Ser. hist. nat. - 13 • 2003 • 1 lakov PULCTČ el si: ON THE RECORD OF MADEIRA ROCKFISH SCORPAtNA MADURENSIS VALENCIENNES, 1 833, IN T HE EASTERN ADRIATIC. 1 9-22 O VRSTI SCORPAENA MADURENSIS VALENCIENNES, 1 833, UJET! V VZHODNEM JADRANU Jakov DULČIČ, Ann in PALLAORO & Sanja MATIČ inštitut za oceanografijo in ribištvo, HR-21000 Split, P.O.BOX 500 POVZETEK Marca 2003 je bila v bližini otočka Daksa pri Dubrovniku ujeta Scorpaena madurensis Valenciennes, 1833. Po razpoložljivi literaturi je to šele drugi podatek za to vrsto v vzhodnem Jadranskem morju. Predstavljeni morfome-trični in meristični podatki so prvi za to vrsto iz vzhodnega Jadrana, Ključne besede: Scorpaena madurensis, drugi podatek, vzhodni Jadran REFERENCES Bint, G. (1968): Atlante dei Pesci delie Coste Itaiiane. Vols. V, VI. Mondo Somerso, Milano. Economidis, P. S. & H. K. Daoulas (1981): The Scorpi-onfishes (Pisces, Scorpaenidae) of the North Aegean Sea. Bull. Mus. natl. Hist, nat., Paris, 4 ser., 3, section A, no. 4, 1219-1224. Hureau, J.-C. & N. I. Litvinenko (1986): Scorpaenidae. In: Whitehead, P. J. P., M.-L. Bauchot, J.-C. Hureau, J. Nielsen & E. Tortonese (eds.). Fishes of the Northeastern Atlantic and the Mediterranean. UNESCO, Paris, Vol. 3, 121 1-1229. jardas, I. (1985): Check-list of the fishes (sensu lato) of the Adriatic Sea (Cyclostomata, Selachii, Osteichthyes) with respect of taxonomy and established number. Bio-sistematika, 1, 45-74. Jardas, I. (1996): Jadranska ihtiofauna. Skolska knjiga, Zagreb, 533 pp. Kaspiris, P. (1976): New fish records from the Greek part of the Ionian Sea. Rev. Trav. Inst. Peches marit., 40, 627-628. Kolombatoviif, J. (1904): Contribution! alia fauna dei vertebrati dei la Dalmazia. Glas. hrv. narav. druStva, 15, 182-191. Lanfranco, G. G. (1993): The fish around Malta (Central Mediterranean). Progress Press, Malta, 132 pp. Lipej, L. & J. Dulcic (in press): Fish diversity - what is new in the Adriatic Sea? In: Griffiths, H. I„ 8. Krystufek & j. M. Reed (eds.). Balkan Biodiversity. Pattern and Process in Europe's Biodiversity Hotspot. Kluwer Academic Publishers B.V. Morato, T., P, Alfonso, P. Lourinho, J. P. Barreiros, R. S. Santos & R. D, M. Nash (2001): The length-weight relationships for 21 coastal fish species of the Azores, northeastern Atlantic. Fish. Res,, 50, 297-302, Riera, F., A. M. Grau, Pastor & S. Pou (1995): Faunistical and demographicai observations in balearic ichthyofaLina. Meridization or subtropicalization phenomena. In: Actes Colloque sci. "La Mediterranee: Variabilities climatiques, Environnement et Biodiversite". Montpellier, France, p. 213-220. Schneider, W. (1990): FAO species identification sheets for fishery purposes. Field guide to the commercial marine resources of the Gulf of Guinea. Prepared and published with the support of the FAO Regional Office for Africa. FAO, Rome, 268 pp. Tortonese, E. (1975): Osteichthyes (Pesci Ossei). Parte seconda. Fauna d'ltalia, vol. XI. Calderini, Bologna, 636 pp. Vacchi, M., M. Boyer, S. Bussotti, P. Guidetti & G. La Mesa (1999): Some interesting species in the coastal fish fauna of Ustica Island (Mediterranean Sea). Cybium, 4, 323-331. 22 MORSKA BIOLOGIJA IN EKOLOGIJA BIOLOGIA ED ECOLOGIA MARINA MARINE BIOLOGY AND ECOLOGY ANNALES ■ Ser. hist. nat. • 13 ■ 2003 • 1 origina! scientific article . UDK 639.4:574.6(262.3-18) received: 2003-03-17 ESTIMATING THE CARRYING CAPACITY OF COASTAL AREAS POTENTIALLY SUITABLE FOR MUSSEL CULTURE IN THE UPPER ADRIATIC, CROATIA Barbara SLADONjA institute for Agriculture and Tourism, HR-52440 Poteč, P.O. Box 31 E-ma i i : barbara@iptpo.hr Radovan ERBEN, Ivana MAGUIRE, Goran KLOBUČAR & Jasna LAJTNER Department of Zoology, Faculty of Science, University of Zagreb, HR-10000 Zagreb, Rooseveitov teg 6 ABSTRACT This paper deals with the application of a carrying capacity model, designed to evaluate the suitability of ten coastal inlets situated on islands in the upper Adriatic Sea for mussel production, and to estimate a potential production quantity. This approach allowed the estimation of a potential carrying capacity of the researched stations and suggestions for a possible launch of mussel production in these areas. The results of this study are considered to be useful for the management of coastal areas suitable for bivalve farming, especially in this particular case of island development II has been established that the model was suitable for evaluation and that all selected stations have good conditions and carrying capacity for mussel production. Mussel farming could, therefore, improve the island economy. Key words: carrying capacity, mussel farming, dimensioning of mussel farms, island development, Croatia VALUTAZIONE Di AREE COSTALI POTENZ!ALMENTE IDONEE ALLA MITILICOLTURA NEL NORD ADRIATICO, CROAZÎA S INT ESI L'articolo tratta l'applicazione del modello di capacita portante destínalo alla valutazione dell'idoneità alla mi-tilic.olr.ura di dieci insenature costaíi sitúate su isole del Nord Adriático e alla stima délia quantité di produzione Potenziale. L'approcclo permette la valutazione délia capacita portante potenziale delle stazioni studiate, nonché la fonnulazione di proposte per un possibile lancio de/la mitilicoltura in tali aree. I risultati del presente studio ven-gono considerad vantagglosi per la gestione delle aree costal i idonee alla col tura di bivalvi, in particotare nell'ambito dello sviluppo insulare. Il modello si è rivelato adatto alla valutazione e tutte le stazioni prescelte hanno dimostrato di avere condizioni e capacita portanti favorevoli alla mitilicoltura. La coltura di mitili perianto potrebbe migliorare l'economia insulare. Parole chiave: capacita portante, mitilicoltura, climensionamento di mitilicolture, sviluppo insulare, Croazia 25 ANNALES • See. hist. nai. • 13 - 2003 • 1 Barbara SLADONjA e! al.: ESTIMATING THE CARRYING CAPACITY OE COASTAL AREA5 POTENTIALLY SUITABLE FOR MUSSEL CUI.TURE .... 25-32 INTRODUCTION The coast of Croatia and especially its islands have a number of areas potentially suitable for sea organism farming. Seashetl farming has a long tradition on the eastern Adriatic coast, probably dating from the Roman period, but the first written documents originating from the 16,h century describe Mali slon Bay. in the 20th century, seafood farming intensified on over 30 localities from Slovenian coast down to Boka Kotorska Bay (Basioli, 1981). Former seafood production (during the Austro-Hungarian Empire) was much higher than today. The Austrian Fishery and Maricult.ure Society used several locations on the coast and islands for oyster and blue mussel culture (Quinto Congresso generale delia Società Austriaca di Pesca e piscicoltura marina, 1893). One of the main social and economical problems in Croatia today is maintaining the population on the islands and revitalising the economy. Aquaculture could be one of the main economy branches on the islands and on the coast in general. Aquaculture is characterised by great dependence on the quality and productivity of the environment, its development also bears a risk of negative environmental impact, such as pollution, landscape modification, or biodiversity change. Aquaculture development needs to follow the rules for use and conservation of natural resources in aquatic ecosystems (Bussani, 1983). Aquaculture as a renewable resource is a capital thai: must ensure a sustainable flow of benefits to users. Coastal zones are always subjects of different conflicting needs, which include recreational and tourist requirements, navigational access and traditional commercial fishing rights. Optimisation of available space is consequently a challenge that also faces the developing aquaculture industry. Few mussel species are fanned all around the world. The world production in 2000 exceeded 1.5 million. More than 20 countries have significant production, although only two of them dominate the market, i.e. China with 40% of the total world production and Spain with 20%. On the eastern Adriatic coast, the majority of shell production is located in Mali ston Bay {90% of total production), with other larger farms situated in Lim Bay, Piran Bay, mouth of the river Krka, and Budava Bay (Hrs-Brenko, 1985). In 1984, 300 t of mussels, 40 t of oysters and 260 t of blue mussels were produced in Mali ston Bay (Benovs^:, 1980, 1997). Considering the natural features of our coast, it could be said that the seafood production is still far from possible and satisfactory. The most farmed mussels are those belonging to the genus My (i lus (M. edults - blue mussel), while the genus Perna (former green mussel) is farmed in warmer waters, as around Thailand, China or New Zealand. : The capacity at the Gulf scale depends on primary production, trophic relationships, and modification of bio-geochemical cycles and community structure in the vicinity of culture sites (Foster-Smith, 1975; Frechette & Bourget, 1985; Frfechette etal., 1991, 1992). On a smaller scale, however, the possibility of local food depletion should be considered, in many coastal ecosystems, bivalve suspension feeders, such as mussels, oysters and clams, occur in high densities. Feeding is performed by pumping and filtering large volumes of water through gills. Due to the filtration activity by bivalves, depletion of organic matter, bacteria and phyto-plankton in the overlying water has been observed in various ecosystems (MohSenberg & Riisgard, 1979; Wright ef al.f 1982; Mantoura & Llewellyn, 1983; Frechette & Bourget, 1985). Indeed, dense arrays of long lines are likely to lead to a depletion of seston (Loo & Rosenberg, 1989), which could affect the optimal size of growing sites, a problem thai: has been considered by Incze et al. (1981}. In addition, local depletion of seston raises the issue of determining the optimal distance between the sites, as they should be positioned in such a way to enable water replenishment by mixing and plankton growth before reaching next downstream site. Early attempts to assess the impact of shellfish aquacuiture focused on the issue of carrying capacity, or the ability of the system to support shellfish production were made (Incze et ai, 1981; Loo & Rosenberg, 1989). More recently, the emphasis has been on modelling the impact of shellfish (Rodhouse & Roden, 1987). A carrying capacity model has been tested by applying it to ten island bays in the upper Adriatic. The model is based on particle and not on energy flow. The main objective was to test the model, and to apply it in specific conditions of the chosen bays. A three-season field programme was undertaken to assess the spatial and periodical distribution of total and organic seston and transport mechanisms of water and seston in the vicinity of a site. These terms of the seston budget were used to determine the dominant processes involved, and thus to evaluate the possibility of launching mussel fanning. MATERIALS AND METHODS Location The study was carried out in the upper Adriatic Sea, on four Croatian islands. Ten potentially suitable stations for mussel farming were investigated (Fig. 1): Cres island: Pogana Bay (si. 1), Krk Island: Puntarska draga (st. 2) and Soline Bay (st. 3), Rab Island: St. Eufemija Bay (st. 4), Kamporska draga {st. 5), Lopar Bay (st. 6) and Supetar Bay {st. 7), Pag Island: Caska Bay {st. 8), Stara Novalja Bay (st. 9), and Stara Povljana Bay (st. 10). 26 ANNALJES • Ser. hist. nat. ■ 13 ■ 2003 • 1 Baibara SIADON1A el al.: ESTIMATING '[HE CARRYING CAPACITY OF COASTAL AREAS PO'TCNTIAUY SUITABLE TOR MUSSEL CULTURE .... fig. 1: Ten investigated stations along Croatian islands potentially suitable for mussel farming. SI. 1; Deset raziskanih vzorčišč vzdolž hrvaških otokov, potencialno primernih za školjkarstvo. Sampling Sampling took place in the winter (February) of 1998, and in the summer (July) and autumn (December) .of 1999. Three replicates of water samples were taken at 0,5 and 10 m using a 5 I Niskin bottle. Currents were ■measured by a pseudo-eulerian method using Andria's cross (Mosetti, 1979). Compass recorded the direction. Methods Total particulate matter or seston (TPM) and particulate organic matter (POM) was determined as triplicates in the Zoology Department of the Faculty of Science. Samples for seston analysis in triplicates of 250 mi were filtrated on combusted and pre-weighied Whatman GF/F filters. The filters were transferred to a 60"C drying oven for 24 hours. On the following day, filters were weighted to obtain values of TPM and combusted at 450 to 500°C for 24 h arid re-weighted to estimate particulate inorganic matter (PiM) and POM (Magazzti, 1984). We used standard statistic equations (standard deviation and t-test). : Filtration rate is defined as the rate of removal of particles from a suspension in which the animals feed, or a measure of the equivalent volume of water that must have been filtered to account for the rate of removal (CoughIan, 1969; Foster-Smith, 1975; Meyhofer, 1985; Prins et al., 1994; Riisgird, 2001). We used literature data for calculating the filtration rate. In Table 1, values of bl ue mussel filtration rates are presented,' FihSlly, :we used the average filtration rate for the blue mussel; Food supply is a function of water movement and quantity of particles in the water, whereas food demand is a function of filtration rate and food concentration. Carrying capacity is calculated by dividing food supply with food demand. Tab. 1; Data of mussel filtration rate from bibliography. Tab. I; Podatki iz bibliografije o hitrosti filtracije školjk. Mussel filtration rate (1/h) Bibliographic source 2.06 foster-Smith (1975) 0.33-1.25 (0.79) Foster-Smith (1975) 0.35-1.05 (0.7) Foster-Smith (1975) 1.54 Foster-Smith (1975) 1.47 Foster-Smith (1975) 1.2-3.4 (2.3) Schuite (1975) 0.S-2.0 (1.25) Mohlenberg & Riisgard (1979) 1-2.5 (1.75) Widdows ef al. (1979) 2.SO MartinCic (1998) t .60 average value The modelling approach itself has shown certain weaknesses, including sensitivity to a restricted set of underlying assumptions and insensitivity to a potentially wide array of unspecified parameters. Despite these numerous limitations, approximations of carrying capacities for intensive cultivation remain of interest. The salient feature of both models is that it is based on particle flow, and not on energy flow. Clearly, the limitations of the modelling approach are not eliminated by these simplifications. This model is offered as an approach, and not as a unique solution. The model is based on water movements and on the seston quantity in the area. A biological concept of the carrying capacity can be defined as the stock density at which production levels are maximized, without a negative environmental impact. The carrying capacity model studied here is based on balance between mussel nutritive needs and food supply within the system. The estimation of the carrying capacity of bivalves in open systems is rendered difficult due to several factors: 1) seasonal and size-related changes in the energy demands of the cultured organisms;-2) seasonal changes in the abundance and nature of potential food substrates found in natural waters; 3) general lack of knowledge concerning the degree to which bivalves utilize various particles in the seston, and 4) difficulties of quantifying mixing and flow through most culture areas. The mode! of Carver & Mallet (1990) was developed in Canada (Nova Scotia). Authors used a somewhat simplistic but practical approach to determine estimates of carrying capacity for a mussel operation in a semi-closed coastal inlet on the Atlantic coast. Rather than 27 ANNALES • Ser. hist. nat. • 13 • 2003 • 1 Barbara Sl.ADONfA el si.: ESTIMATING THE CARRYING CAPACIT Y Of COASTAL AREAS POTENTIALLY SUITABLE FOR MUSSEl CULTURE .... 25-32 relying on laboratory-derived values, authors obtained extensive field data on water exchange, food levels and in situ mussel filtration rates. The volume of the Basin was estimated as well as the volume of water flowing in and out of the system in each tidal cycle. Data of suspended particulate matter was used in order to calculate food levels (food supply and food demand). Finally, carrying capacity was obtained dividing food supply by food demand. Equations are presented in Table 4. RESULTS AND DISCUSSION Environmental study Current velocities are shown in Table 2. As expected, the strongest currents were measured in winter as a consequence of meteorological conditions. We did not find significant differences between stations. Measurements of the currents gave us results comparable with other authors (Princi et a/., 1980; Stravisi & Battista, 1992). Two current types are usually present in the Adriatic (Mosetti, 1966). On a large scale, there is a constant slow current below 10 m depth, parallel to the coast in the northern direction. On a small scale, currents are influenced by wind, tide and morphological circumstances. It is Important for good water quality in mussel farms to have fast water exchange and currents able to replenish the water quite frequently. The biggest bay is Caska on Pag Island, while the smallest is Pogana on Cres Island. As far as the bay volume is concerned, the largest goes to St. Povljana Bay on Pag, and the smallest to Punat Bay on Krk. In Table 4, all hydrologic data about bays is presented (water tidal oscillations, water surface and volume, water exchange). Water exchange in all examined bays showed good results (from 5-30% of water exchange/day). For example, the Gulf of Trieste that is known for its high number of mussel farms (Martincic, 1998) has an average water exchange of only 7%. The bay studied by Carver & Mallet (1990) had a water exchange of approx. 50%. Tills is particularly important for water replenishment that depends not only on tidal currents but also on permanent currents and also imports from the land. Temperature, salinity and oxygen are parameters closely linked with each other and connected with external meteorological and hydroiogicai conditions. Their variations are mostly of temporal character. During winter, the water column is homogeneous due to strong water mixing, while in spring it is possible to observe water stratification, which continues into and through the entire summer (Marchetti & Cotta Ramusino, 1992). Stratification is present both for temperature (presence of thermocline) and salinity (picnocline). In spring, superficial water in fact heats up, and due to the freshwater income from the land the salinity varies greatly between the sea's surface and floor. Tab. 2: Current velocities at sampling stations. Tab. 2: Hitrosti tokov na vzorciscih. | Stations Winter Summer Autumn 1 9.5 15.2 0.07 2 0.6 12.5 10.0 3 5.9 0.9 0.9 4 18.0 14.7 8.3 5 12.8 16.7 0.1 6 26.3 16.7 8.3 7 10.2 9.5 10.5 8 12.5 7.1 14.9 1 9 15.0 8.3 8.3 L to 0.3 0.3 0.3 Analysis of TPM showed a maximum concentration of particulate matter in summer (Tab. 3). Considering the low depth of water at most stations, high TPM values are probably a consequence of bottom resuspension. The obtained data were not significantly different between stations. The relatively high standard deviations can be explained with the fact that these values are calculated as an average of three depths (0, 5 and 10 m). These are depths at which mussels are farmed and although different they were not statistically significant. For further calculations, we thus decided to work with average data. The lowest POM concentration was recorded in winter, the highest in autumn. Differences between winter and summer as well as between winter and autumn are statistically significant (t-test ~ 0.000828, t-test = 0.002804), while those between summer and autumn are not significant (t-test = 0.285358), All the examined stations had a good quantity of POM, ranging between 1,2 mg/l (Lopar and St. Novalja Bays) and 4.2 mg/l in St. Povljana Bay. TPM is related to land contributions and also to phytoplankton production (Schulte, 1975; Valli, 1980; Fonda Umani & Ghirardelli, 1988; Williams & Claustre, 1991). Suspended matter is usually composed of Inorganic detritus, especially close to the shore or in shallow waters. Even by taking this into consideration, we found some relatively high concentrations of organic matter, with values ranging from 14% (winter) to 77% (autumn) of POM. Bayne & Widdows (1978) recorded, for the coastal area of Spain, values from 3 to 100 mg/l of TPM, with only 5-30 % of organic components. Our results can be well compared to data measured in the Gulf of Trieste (Adriatic Sea). Authors measured from 0.7 to 4 mg/l of TPM, with 25 to 31% of organic matter (Fonda Umani & Ghirardelli, 1988). Since the organic component is formed by live planktonic organisms and organic products of biode-position, it is normal that we found the lowest concentration of organic matter in winter, when no planktonic 28 ANNALES • Ser. hist. nat. • 13 • 2003 • 1 Barbara SLADONjA et ai: ESTIMATING THE CARRYING CAPACITY OF COASTAL AREAS POTENTIALLY SUIÏAIÏLE FOR MUSSEL CULTURE ...,25-32 Tab. 3: Mean values (±s.d.) of total particulate matter (TPM) and particulate organic matter (POM) during three seasons at ten sampling stations. Relative contribution of POM as % of TPM is also shown. Tab. 3: Srednje vrednosti (±s.d.) celotne suspendirane snovi (TPM) in partikulatne organske snovi (POM) v treh sezonah na desetih preučevanih vzorčiščih. Prikazan je tudi relativni prispevek POM kot % TPM. Station Winter Summer Autumn TPM (mg/l) POM (mg/l) POM (% of TPM) TPM POM POM (% of TPM) TPM POM POM (% of TPM) 1 3.3 (1.0) 0.4 (0.3) 14.0(11,5) 4.1 (1.7) 2.6 (0.8) 68.0 (20.7) 3.5 (0.9) 2.0 (0.3) 60.0(11.0) 2 3.4 (1.4) 0.9 (0.1) 28.7 (8.1) 3.3 (1.0) 2.2 (0.5) 69.0 (7.5) 3.8 (1.7) 1.5 (0.9) 39.7(15.6) 3 3.9 (0.8) 1.2 (0.1) 31.0 (2.8) 6.3 (3.3) 3.0(1.2) 48-0 (22.3) 3.5(1.1) 1.3 (5.7) 37.0(15.5) 4 17.8 (20.5) 1.7(1.1) 18.0(10.5) 7.4 (2.0) 1.8 (0.9) 25.3(12.5) 3.0(1.8) 2.1 (0.7) 75.3 (15.9) 5 3.0(1.6) 0.5 (0.3) 17.3 (4.2) 4.3 (2.9) 1.9 (0.6) 49.7(13.7) 2.6 (1.0) 2.0 (0.7) 76.7 (4.2) 6 4.8 (4,0) 0.7 (0.0) 21.0 (13.1) 4.1 (2-3) 1.7(0.7) 47.3 (15.3) 7.0 (5.8) 1.3 (0.5) 22.3(8.1) 7 3.8 (1.4) 0.8 (0.4) 22.0 (6.9) 4.3(1.9) 1.8(0.3) 44.7 (11.7) 2.6(0.6) 1.2(0.2) 48.3 (19.5) 8 6.8 (4.8) 1.6 (0.8) 25.0 (5.6) 7.1 (4.0) 3.9(1.1) 62.0 (17.1) 3.4(1.1) 1.7(0.6) 50.3 (4.5) 9 3.0 (0.7) 1.1 (0.3) 35.7 (7.8) 2.6 (0.3) 1.3 (0.4) 50.3 (19.8) 2.9 (0.4) 1.1 (0.4) 36.7(7.5) 10 2.3 (0.6) 0.5 (0.1) 22.0 (7.8) 18.0 (6.5) 4.2 (1.3) 23.0 (9.8) 2.8(1.3) 1.8 (6.0) 64.0 (25.3) blooms are present, and the highest percentage in autumn due to the active planktonic bloom or scenes-cent phase of the bloom (Marchetti & Cotia Ramusino, 1992). Carrying capacity mode! There is an abundance of data in literature on the influence of water flow on the particles or food concentration (Dame et a/., 1980; Incze ef a/., 1981; Cloern, 1982; Frechette & Bourget, 1985; Loo & Rosenberg, 1989). in estuaries, the seston movement is dominated by the river outflow, while in the coastal inlets it is primarily determined by tidal currents, which are often very weak. Food supply in the water depends not only on the water flow but also on the quantity and quality of particles present in it (Zentilin & Pellizzato, 1996). Variations in food supply are in relation to tidal oscillations and thus to tidal volume, as well as to POM oscillations in the water. We observed that maximum POM levels at our stations were comparable to the values reported in other mussel studies (Bayne & Widdows, 1978; Widdows ef at., 1979; Wildish & Kristmanson, 1984; Carver & Mallet, 1990). Values lower than 1 mg/i are common along the Atlantic coast, while higher values are generally characteristic of estuaries and coastal inlets (Carver & Maliet, 1990). The lowest food supply was noted for the wintertime, as a result of the low primary production. Among the stations, we calculated the highest quantity of food supply in Caska and St. Povljana Bays on Pag island. Rodhouse & Roden (1987) found that zooplankton compete with cultured mussels for food particles and estimated that herbivorous zooplankton consume 29% of the annual phytoplankton production in Killary Harbour, Ireland. On the other hand, recent evidence suggests that mussels can significantly reduce microzoo-plankton levels (Incze et ai, 1981), thereby effectively decreasing food competition. Given that increasing stock densities have a positive effect on primary production, our estimates of food supply should eventually include not only the POM delivered to the system, but also locally produced POM. Food demand was calculated with estimates on filtration rate and food concentration. At our sites, there were always enough particles present in the water to satisfy the average filtration needs by mussels. Mussels consume live and inorganic particles in the water (plankton and detritus). Since we did not find significant differences in carrying capacities measured in winter, summer and autumn, average data is presented (Tab. 4). In the end, we concentrated on potential differences between stations. Relatively large water volumes and high POM concentrations gave high carrying capacities. St. Novalja and St. Povljana Bays had a carrying capacity higher than 2000 t. The lowest carrying capacity was calculated for Pogana (about 600 t). In estimating the carrying capacity, we assumed that the mussels had access to 100% of the available food supply. This approach does not allow factors such as incomplete mixing of particles in the Gulf, loss of particles in the outflow, and contamination of "new" particle-rich water by "old" particle-depleted water from the previous tidal cycle. A positive effect of mussel stock densities on nutrient regeneration, which can enhance local primary production, should also be considered. 29 ANNALES ■ Ser. hist. nat. • 13 • 2003 • 1 Batbuta SlADONjA etui.: ESTIMATING THE CARRYING CAPACITY OF COASTAL AREAS POTENTIALLY SUITABLE FOR MUSSEL CULTURE .... 25-32 Tab. 4: Carrying capacity equations and hydrologicai data for the ten sampling stations. Tab. 4: Enačbe za izračun nosilnosti okolja in hidrološki podatki za deset vzorčišč. Parameter Equation Cres Krk Krk Rab Rab Rab Rab PaR Pa* PaS st. 1 sf. 2 st. 3 st. 4 st. S st. 6 st. 7 st. S s!. 9 st. 10 a Average ebb tide (cm) 32.2 32.2 32.2 32.2 32.2 32.2 32.2 32.2 32.2 32.2 b Average high tide (cm) 30.3 30.3 30.3 30.3 30.3 30.3 30.3 30.3 30.3 30.3 c Daily oscilations (cm) (a+b) x 2 17.5 125 125 125 125 125 125 125 125 125 d Tidal volume per day (x 10" m3) c x i 201 377 430 320 463 271 560 1398 675 1030 e Tidal volume per week (x 1Q4 m3) d x 7 1407 2644 3016 2246 3244 1903 3920 9789 4731 7211 f Bay volume in ebb tide (x 10" m3) M/2 1217 878 1106 2344 9732 2426 6274 11487 10683 15714 8 Bay volume in high tide (x 10* tn3) j+d/2 1418 1255 1537 2665 10196 2697 6834 12886 11359 16745 h Water exchange per day (%) d/g 14 30 28 12 5 10 8 11 6 6 i Total by surface (Aioi) rrr 1609300 3024209 3449123 2569200 3710500 2176800 4482500 11194100 5410100 8245700 j Bay volume (V,0i) x 1m3 1318 1067 1322 2505 9964 2562 6554 12187 11021 16230 k POM (mp/l) 1.7 2.6 2.4 1.9 1.5 1.2 1.3 2.4 1.2 4.2 I Food supply (x 106 S POM/week) e x k 23.4 68.4 72.4 42.0 47.6 23.4 49.4 233.2 55.1 202.1 m Food demand (g POM/kg mussels/week) k/1000 x 1.6 x 24h x 7 x 83 37.2 57.3 53.5 41.6 32.7 27.5 28.3 53.5 26.0 62.5 Carrying capacity (tons of mussels) l/m 629 1193 1353 1010 1456 851 1746 4359 2119 3234 All the sites have shown to be suitable for mussel production. Carrying capacities higher than 500 t can be considered as high. The lowest recorded carrying capacity was in Pogana Bay on the island of Cres (600 t). Generally, the best island for mussel production should be Pag, where all three bays showed very high carrying capacities (higher than 2000 t). CONCLUSIONS It. can be concluded that all the examined sites on Croatian islands are suitable for mussel farming. The present study only confirmed this statement already known to national experts. Mariculture could be an ad- ditional motive and way of earning money for these island populations, as well as incentive for new people settling there. Among 10 sites, the best are those on the island of Pag, but none turned out to be non-suitable for mussel farming. Similar study should be performed on other islands and new locations for this economic activity suggested. ACKNOWLEDGEMENTS The project was financially supported by the Croatian Ministry for Public Works and Reconstruction. 30 ANNALES • Ser. hist. nat. • 13 • 2003 • 1 8arl»ra 51.ADONJA et ai: ESTIMAI ING THE CARRYINC CAPACiTV OF COASTAL AREAS POTÉNTiALLY SUITASEE FOR MUSSEt. CULTURE ..., 25-32 OCENJEVANJE NOSILNOSTI OKOLJA V SEVERNOJADRANSKIH OBALNIH OBMOČJIH, POTENCIALNO PRIMERNIH ZA VZGOJO ŠKOLJK Barbara SLADONJA Institute for Agriculture and Tourism, HR-S2440 Poreč, P.O. Box 31 E-rnail: barbara@iptpo.hr Radovan ERBEN, Ivana MACUIRE, Coran KLOBUČAR & jasna LAjTNER Department of Zooiogy, Faculty of Science, University of Zagreb, HR-10000 Zagreb, Rooseveltov trg 6 POVZETEK V desetih manjših zalivih ob severnojadranskih otokih je bil uporabljen model za ugotavljanje nosilnosti tamkajšnjega morskega okolja. Študija, katere namen je bil ugotoviti primernost teh voda za gojenje školjk, je slonela na terenskih podatkih o izmenjavi vode in količini hrane v njej, dobljenih med vzorčenjem pozimi, poleti in jeseni leta 1999. Rezultati so pokazali, da so vse preučevane lokalitete primerne za školjkarstvo. Najnižja nosilnost okolja je bila ugotovljena v zalivu Pogana na Cresu, sicer pa je bila izmenjava vode zadostna v vseh preučevanih zalivih (od 5-■30% na danj. Dobljene rezultate bi lahko uporabili za upravljanje obalnih območij, primernih za vzgojo školjk, posebno v primerih načrtovanega otoškega razvoja. Školjkarstvo bi lahko seveda močno izboljšalo otoško gospodarstvo. Ključne besede: nosilnost okolja, školjkarstvo, dimenzioniranje školjčišč, otoški razvoj, Hrvaška REFERENCES Basioli, J. (1981): Uzgoj školjkaša na istočnoj obali jad-ranskog mora s posebnim osvrtom na Malostonski zal-jfev. Zbornik radova savjetovanja "Malostonski zaljev pnrodna podloga i društveno valoriziranje", Dubrovnik, 1981, str. 268-282. Bayne, B. L. & j. Widdows (1978): The physiological ecology of two populations of Mytilus edulis L. Oecolo-gia, 37, 137-162. Benovic, A. (1980): Razvoj marikulture u kanalu Ma log Stona. Morsko ribarstvo, 32(1), 26-28. Benovic, A. (1997): The history, present condition, and future of the molluscan fisheries of Croatia. NOAA Tech. Rep. NMFS, 129, p. 217-226. Bussani, M. (1983.): Cuida pratica di mitiiicoltura. Edagricole, Bologna. Carver, C. E. A. & A. L. Mallet (1990): Estimating the carrying capacity of a coastal inlet for mussel culture. Aquaculture, 88, 39-53. cioern, J. E. (1982): Does the benthos control phyto-plankton biomass in South San Francisco Bay? Mar. Ecol. Prog. Ser., 9, 191-202. Coughlan, J. (1969): The estimation of filtering rate from the clearance of suspension. Mar. Biol., 2, 356-358. Dame, R. F., R. Zingmark, H. Stevenson & D. Nelson (1980): Filter feeding coupling between the estuarine water column and benthic subsystems. In: Kennedy, V.S. (ed): Estuarine Perspectives. Academic Press, New York, p. 521-526. Fonda Umani, S, & E. Ghirardelli (1988): Caratteristiche chimiche e biologiche del sisterna pelagico del Golfo di Trieste. Hydrores, V(6), 71-82. Foster-Smith, R. L, (1975): The effects of concentration of suspension on the filtration rates and pseudofaecal production for Mytilus edulis L., Cerastoderma edule (L.) and Venerupis pullastra (Montagu). J. Exp. Mar. Biol. EcoL, 17, 1-22. Frechette, M. & E. Bourget (1985): Energy flow between the pelagic and benthic zones: factors controlling particulate organic matter available to an int.ertidal mussel bed. Can. J. Fish. Aquat. Sci., 42, 1 158-1 165. Frechette, M., D. A. Booth, B. Myrand & H. Berard (1991): Variability and transport of organic seston near a mussel aquaculture site. ICES Mar. Sci. Symp., 192, 24-32. Frechette, M., A. E. Aitken & t. Pag6 (1992): interdependence of food and space limitation of a benthic suspension feeder: consequences for self - thinning relationships. Mar. Ecol. Prog. Ser., 83, 55-62. 31 ANNALES • Ser. hist. nat. • 13 • 2003 • 1 Barbara SLADONJA et al.: ESTIMATING THE CARRYING CAPACITY OP COASTAl. AREAS POTENTIALLY 5UITAGLE FOR MUSSEL CULTURE ..., 25-32 Hrs-Brenko, M. (1985); Marikultura. Pomorski zbornik, 23(1}, 217-236. Incze, 1. S., R. A. Lutz & E. True (1981): Modeling carrying capacities for bivalve molluscs in open, sus-pended-culture systems. }. World Marie. Soc., 12(1), 143-155. Loo, L. O. & R. Rosenberg (1989): Bivalve suspension-feeding dynamics and benthic-pelagic coupling in an eutrophicated marine bay. j. Exp. Mar. Biol. Ecol., 130, 253-273. Magazzu, G. (1984): Metodi di analisi per acque di mare. Materiale in sospensione. Método gravimetrico. Quad. 1st. Ric. Acque, 59. Mantoura, R. F. C. & C. A. Llewellyn (1983): The rapid determination of algal chlorophyll and carotenoid pigments and their breakdown products in natural waters by reverse-phase high-performance liquid chromatography. Anal. Chim. Acta, 151, 297-314. Marchetti, R. & M. Cotta Ramusino (1992): Ecología. Atti V Congresso Nazionale della Societa Italiana di Ecologia, Milano, 21-25 Setiembre 1992. MartinÉic, B. (1998): Modello di carrying capacity ap-plicato alie mitilicolture in sospensione. Ph.D. thesis. Universita degli studi di Firenze, Pisa e LJdine, p. 15-108. Meyhófer, E. (1985): Comparative pumping rates in suspension-feeding bivalves. Mar. Biol., 85, 137-142. Mohtenberg, F. & H. U, Riisgárd (1979): Filtration rate, using a new indirect technique, in thirteen species of suspension-feeding bivalves. Mar. Biol., 54, 143-148. Mosetti, F. (1966): Cortsideraziorti preliminari sulla dinámica dell'Adriatico Settentrionale. Arch. Oceanogr. Limnol., 15 (Suppl.), 237-244. Mosetti, F. (1979): Fondamenti di Oceanología e Idrologia. Unione Tipográfica - Editrice Torinese, Torino, p. 458-475. Princi, M., F. Stravisi & M. Specchi (1980): Osservazi-oni morfologiche, fisiche e chimiche sulla Baia di Mug-gia (Golfo di Trieste - Alto Adriático). Mem. Biol. Mar. Oceanogr., 10 (Suppl.), 275-284. Prins, T. C., N. Dankers & A. C. Smaai (1994): Seasonal variation in the filtration rates of a semi-natural mussel bed in relation to seston composition, j. Exp. Mar. Biol. Ecol., 176, 69-86. Rirsgard, H. U. (2001): On measurements of filtration rates in bivalves - the stony road to reliable data: review and interpretation. Mar. Ecol. Prog. Ser., 211, 275-291. Rodhouse, P. G, & C. M. Roden (1987): Carbon budget for a coastal inlet in relation to intensive cultivation of suspension - feeding bivalve molluscs. Mar. Ecol. Prog. Ser., 36, 225-236. Schulte, E. H, (1975): Influence of algal concentration and temperature on the filtration rate of Mytilus edulis. Mar. Biol., 30, 331-341. Stravisi, F. & G. Battista (1992): Correntometria costiera nel Golfo di Trieste. Rapporto Interno LC 92/4. Labora-torio di Climatologia, Dipartimento di Fisica Teorica, Universita degli Studi di Trieste. Valli, G. (1980): Riproduzione ed a cc re set men to di al-cune specie di molluschi eduii nelle Lagune di Grado e marano. Nova Thalassia, 4(SuppL), 49-65. Widdows, J., P. Fieth & C. M. Worrall (1979): Relationships between seston, available food and feeding activity in the common mussel MytHus edulis. Mar. Biol., 50, 195-207. Wildish, D. J. & D. D. Krisimanson (1984): Importance to mussels of the benthtc boundary layer. Can. j. Fish, Aquat. Sci., 41, 1618-1625. Williamson, R. & H. Claustre (1991): Photosynthetic pigments as biomarkers of phytoplankton populations and processes involved in the transformation of particulate organic matter at the Biotrans site (47'N, 20"W). Deep-Sea Res., 38(3), 347-355. Wright, R. T., R. B. Coffin, C. P. Ersing & D. Pearson (1982): Field and laboratory measurements of bivalve filtration of natural marine bacterioplankton, Limnol. Oceanogr., 27(1), 91-98. Zentilin, A. & M. Pellizzato (1996): La molluschicoltura in Italia. Atti XX Convegno Nazionale sui Problemi della Pesca e dell'Acquicoltura, Cesenatico, 11-12 ottobre 1996, p. 113-119. 32 ANNALES - Ser, hist. nat. • 13 • 2003 • 1 review UDK 591.9:574,5(262.3-18) ; received: 2003-03-10 MEIOBENTHIC FAUNA (WITHOUT HARPACTICOiDA) IN THE SOUTHERN PART OF GULF OF TRIESTE, SLOVENIA: LIST OF TAXA Borut VRISER Nations! institute of Biology, Marine Biology Station, S!-6330 Piran, Fomače 41 E-mail: vriser@mbss.otg ABSTRACT The article presents an integral systematic review of meiobenthic fauna (without the already presented Copepoda ■ Harpaclicoida), arranged on the basis of extensive material gathered in the course of numerous investigations during the last 30 years in the southern part of the Gulf of Trieste. The emphasis is on a systematic survey, which includes a ■total of 30 higher taxa with nearly 180 species, although still a minor part of all expected but undiscovered species of the area. Key words: meiofauna, list of taxa, Gulf of Trieste, Slovenia FAUNA MESOBENTONICA {ESCLUSI GL! ARPACTICOIDI) DELLA PARTE MERiDIONALE DEL GOLFO DI TRIESTE, SLOVENIA: LISTA DEI TAXA SINTESi Vaitlcolo presenta una revisione sistemática integrale delta fauna meiobentonica (esclusi i copepodi arpacticoidi :gia presentati), preparata in base at vasto materiale raccolto durante le numeróse ricerche effettuate negli ultimi 30 ■Ami nella parte meridionals del Golfo di Trieste. Posta in rilievo l'indagine sistemática che include 30 taxa superiori :'CÓn" quasi 180 specie, benché queste rappresentino solo una piccola parte di tutte le specie attese ma ancora ■sconosciute dell'area. Paroie chiave: meiofauna, lista dei taxa, Golfo di Trieste, Slovenia 33 ANNALES • Ser. hist. ¡iat. • 13 • 2003 • 1 ¡3 o rus VRISER: MEIOBENTHSC FAUNA (WITHOUT HARPACTICOi DA] IN THE SOUTHERN PART OF GULF OF TRIESTE. SLOVENIA: LIST OF TAXA, 33-« INTRODUCTION The paper presents meiofauna of the southern part of Guif of Trieste, Copepoda excluded. The present work is a continuation of the survey of meiobenthos in the Slovene sea (initiated several years ago), with an emphasis on its species structure and spatial distribution. In the first two articles (Vriser, 2000a, b), the systematic» and ecology of harpacticoid copepods (Copepoda, Harpae-ticoida) as one of the most dominant groups were presented, while the aim of this paper is to outline the taxonomic structure of the remaining meiofauna. Meiobenthos of the southern part of Gulf of Trieste has so far not been researched at: such level as already mentioned harpacticoid copepods. The extent of more complete taxonomic determinations is here incomparably poorer. Amongst the causes for such state of affairs we must highlight, apart from a tmly exceptional bulk of the material itself, mainly the following very specific and excusable reasons: 1. in many groups, particularly in those that are sparse or with more delicate body structure, taxonomic study would require some very special and to them adapted sampling techniques and substantially greater number of parallel samples, as well as often repeated seasonal sampling; 2. even today, many groups remain poorly researched, with insufficient, outdated or hardly accessible literature; 3. lack of suitable specialists or taxonomic consultants; 4. predominantly juvenile character of several groups (temporary meiofauna, i.e. juvenile stages of the future macrofauna), which greatly aggravates precise identification of species; 5. damaged body structures of the more delicate, especially "worm-like" groups owing to the use of routine methods of fauna extraction from the substrate, which are more or less unsuitable for these partictilar groups; 6. incompatibility of the necessary (stated) specific methodological approaches with simultaneous demands of general ecological studies of the great spatial or temporal frequency span. In spite of it all, a fairly clear structural and ecological picture has crystallised from the research lasting for more than thirty years, which in many groups reached a notable degree of a systematic rounding up. The research into some methodologically exceptionally demanding taxa unfortunately remained at its initial stage (e.g. Nemertinea, Nematoda, Oligochaeta, if mentioning only the most abundant ones) and is still waiting to be continued. We believe that in spite of the above-mentioned gaps, fauna other than copepod, too, would deserve its first presentation of a clearer although for the time being still unavoidably preliminary systematic survey. MATERIAL AND METHODS Most of our samplings were implemented with gravity core sampler (Meischner & Rumohr, 1974); only in lagoonar conditions they were also carried out manually, always with three parallel samples in the surface sediment of 10 cm2, 5-10 cm deep. Meiofauna was extracted with the sieving-decantation technique according to Wieser (1960) on 1 mm, 0.125 mm, and 0.050 mm sieves, preserved {4% formalin with seawater), sorted out, counted and, if at all possible, identified to its species. Only a minor part of the meiofauna groups was taxonómically analysed by specialists: Foraminifera (Franc Cimerman, Slovenian Museum of Natural History, Ljubljana), Polychaeta (Andrej Avcin, Marine Biology Station Piran, National institute of Biology, Ljubljana), Tanaidacea (Dusan Zavodnik, Centre for Marine Research, Rudjer Boskovic Institute, Rovinj), Insecta (Ignac Sivec, Slovenian Museum of Natural History, Ljubljana), Bryozoa (Brian M. Marcotte, Clark University, Worcester, USA). For taxonomic determination, authentication and classification of all remaining groups stated in brackets below, the author used the following important references: Bartsch & lliffe, 1985 (Acariña); Bonaduce ei a/., 1975 (Ostracoda); Bouillon & Grohmann, 1990 (Hydro-zoa); Chevreux & Fage, 1925 (Amphipoda); De Mln & Vio, 1997 (Gastropoda, Bivalvia); .Gruner, 1965 (Iso-poda), Higgins, 1977 (Kinorhyncha); Hulings, 1971 (Hydrozoa, Kinorhyncha); Karaman, 1972, 1973, (Amphipoda); Klie, 1938 (Ostracoda); Nordsieck, 1968, 1972 (Gastropoda), 1969 (Bivalvia); Piatt. & Warwick, 1983, 1988 (Nematoda); Riedl, 1956 (Turbeliaria), 1983 (Anthozoa, Cirripedia, Decapoda, Cumacea, Lep-tostraca, Sipunculida, Chaetognatha, Holothurioidea, Asteroidea, Ophiuroidea, Echinoidea, Ascidiacea, Ne-mertinea); Rieger, 1971 (Turbeliaria); Salvini-Plawen, 1966 (Hydrozoa); Sars, 1896 (Isopoda). ECOLOGICAL CHARACTERISTICS OF THE RESEARCHED ENVIRONMENT The so far carried out research into the meiofauna of southern Guif of Trieste has dealt with the entire depth span of these waters: from 0.3-5 m in coastal studies, to the samplings in the Gulf's open waters (19-30 m depth). Meiofauna of the four coastal sampling profiles (1-15 m) in the Bays of Koper, Strunjan and Piran was comparatively researched in the summer and winter months, while the meiofauna of deeper areas was studied only in the summer. Thermic conditions of the entire area range from 9-21 "C, with average salinity of 37.5 psu, oxygen content in the span of 55-96% saturation, except in the very rare 34 ANNALES • Ser. hist, nat. • 13 ■ 2003 • 1 Bomi VRISER: ML IO ¡3 £ NTH IC FAUNA (WITHOUT HARPACTICOIDAI IN THE SOUTHERN PART OF GULF OF TRIESTE, SLOVENIA: LIST OF TAX A, 33-42 periods of hypoxia crisis, when the values can fail below 40%, With the exception of some marginal coastal localities (Koper and Piran Bays), which were at the time of sampling still under a great impact of organic pollution of urban origin, all the remaining meiofauna dealt with in this paper belonged to a clean and unburdened environment. The substrate of the investigated area consists of clayey silt {10-20% clay), which along the coast gradually turns into silty clays {up to 25% of clay) and, towards the open sea, into fine sands (Ogoreiec et al., 1991). TAXONOMiC EXTENT OF RESEARCH iNTO THE MEIOFAUNA OF SOUTHERN GULF OF TRIESTE Taxonomic structure of meiofauna of the selected research area has in fact never been studied purposely {with the exception of harpacticoid copepods), at least not exclusively with this aim, for the emphasis was largely on the ecological complexities and typology of its associations. Although subordinate, it still was a component part of these investigations, whose selection, arranged according to the thematic criterion, is here presented only in a condensed form. In Slovenia, the first ecological meiobenthic research was initiated by Marcotte & Coull (1974) on the coastal profile of Piran Bay. This research was followed by the author's investigations in the experimental basins of Strunjan (Vriser, 1979, 1982), on the coastal profiles of the Bays of Koper, Strunjan and Piran (Vriser, 1983-84, 1986), in the open waters of Gulf of Trieste {Vriser, 1989. 1991, 1992), in the Bays of Strunjan and izola (Vriser, 1999, 2001), and in coastal lagoons (Vriser, 2002). At first, i.e. until the mid-1980s, the investigations were still directed at utterly ecological objectives, dealing primarily with the impacts of pollution on the meio-fauna's associations. Nonetheless, these works contributed most of the taxonomic data presented herewith. To a smaller extent they were supplemented by the long-term studies of seasonal dynamics and meiofauna's long-term oscillations in the centre of Gulf of Trieste (Vriser, 1996, 1997; Vriser & VukoviC, 1999), as well as of its recolonisation characteristics (VriSer, 1998; Vriser & Vukovic, 2000). There are unfortunately no other studies that would have contributed to a clearer picture of the systematic structure of the meiofauna in the southern part of Gulf of Trieste, but let us mention numerous investigations of separate groups of this fauna on at least three sites in the immediate vicinity of our waters, which are due to their closeness of a considerable significance for as well. The first such site is situated close to Trieste (Italy): it is in fact the site of the former marine biology station, where the first meiobenthic determinations were made in the early 20!i' century.....e.g. Grtinspan (1908) with the group Gastrotricha. The second such site is the area around Rovinj (Croatia), where numerous investigations were made in the 1950s and 1960s by a number of taxonomists, such as Riedl (1956) (group Turbellaria), Sterrer {1965, 1967) (group Gnathostomulicla), Schrom (1966a) (group Gastrotricha) and Saivini-Plawen (1966, 1968) (groups Cni-daria, Kamptozoa, Acuiifera). The third interesting site is the area around Venice, where much research was carried out by Schrom (1966b, c), Hummon et al. (1990) and Evans et al. (1993), all concentrating on the group Gastrotricha, and by Rieger (1971) (group Turbellaria). Here follows a survey of all 31 registered higher taxa of the researched meiofauna, arranged in systematic succession (Riedl, 1983). Only some of the groups and species from the list are planktonic, all the rest being benthic. For each group, an approximate estimate of their occurrence in our sea is stated, i.e. their quantitative representativeness (% relative abundance within total meiofauna, hereinafter referred to as rel. ab.) and an estimate of their systematic covering, i.e. of the suppositional and actually established number of species in the area researched. Al! estimates about the probable number of species stated in further text thus refer exclusively to meiofauna. For within the same groups the number of macrobenthic species can be here and there not only higher but also lower than in the meiofauna, i.e. by spatially variable share (number of species) of that particular meiofauna's component, which in contrast to the juvenile macrofauna does not surpass, not even in the adult stage, the size of 1 mm (permanent meiofauna). However, the precise number of these species in the majority of dominant groups of our meiofauna is still not known. FORAMINIFERA Foraminifera, which are no doubt part of meiofauna, are by most meiofaunists omitted from their research for methodological reasons. Namely, with the standard methods of colouring, suitable for the remaining fauna, it is not possible to distinguish between live and dead foraminiferous individuals. Foraminifera can thus be subject of only specialised sampling techniques, extraction, colouring, separation and particularly identification. Occurrence: massive. If taken into account, foraminifera would be one of the first three dominant groups of meiofauna. Number of species: no actual data at hand. All 13 determined species from our list are from the Strunjan lagoon. 35 ANNALES • Ser. hist. nat. • 13 • 2003 • 1 Borut VRSSER: MEIOBENTHIC FAUNA (WITHOUT HARPAC'T'ICOIOA) IN THE SOUTHERN PARTOF GULf OFTRIESTE, 5LOVENIA: EIST OETAXA, 33-42 HYDROZOA Occurrence: rare, more common only here and there, generally below 0.1% rel. ab. Number of species: unknown, perhaps up to 10 species. 5 species determined partially. ANTHOZOA Occurrence: only a few fragments of juvenile individuals were registered, presumably from the group of Anthipatharia. Number of species: unknown. TURBELLARIA Occurrence: mass group in most samples, 1% rel. ab. Number of species: presumably up to 50, almost all of them permanently meiobenthic. 7 species determined partially. NEMERTiNEA Occurrence: rare, below 0.2% rel. ab. Number of species: unknown, no determinations. NEMATODA Occurrence: most abundant, dominant group (70% rel. ab.} throughout in all samples! Number of species: unknown, possibly up to 100, almost exclusively permanent meiobenthic species. Only 4 less common species determined. KINORHYNCHA Occurrence: common group, 0.25% rel. ab. Number of species: about 10 species of permanent meio-fauna, 8 partial determinations. POLYCHAETA Occurrence: third most abundant group (8% rel. ab.). Number of species: unknown, perhaps up to 100 species, to a great extent of temporary character (juvenile macrofauna), 38 species registered and in most cases determined. OLIGOCHAETA Occurrence: very abundant group (2% rel. ab.). Number of species: unknown, perhaps few dozen species. No species determined. OSTRACODA Occurrence: common group, mostly with low abun- dances (0.25% rel. ab.). Number of species: unknown, perhaps over 50 species. 16 species registered and partially determined in our samples. CIRRIPEDIA Only two coincidentally caught juvenile individuals. DIECAPODA Occurrence: rare, generally below 0.1% rel. ab. Number of species: perhaps up to 20 species, 10 more common species partially identified. AMPH1PODA Occurrence: modest, in places somewhat more common, generally below 0.1% rel. ab. Number of species: perhaps up to 30 species, 14 more common species partially identified. 1SOPODA Occurrence: rare individuals, generally below 0.1% rel. ab. Number of species: unknown, 13 species partially determined. MYSIDACEA Occurrence: rare, mostly occurring individually, altogether below 0.1% rel. ab. Number of species: unknown, 4 species partially identified. CUMACEA Occurrence: rare, mostly occurring individually, altogether below 0.1% rel. ab. Number of species: perhaps above 10 species, 4 only partially determined. TANA1DACEA Occurrence: rare, mostly occurring individually, generally below 0.1% rel. ab. Number of species: 4, with 3 of them identified. LEPTOSTRACA A single identified individual. ACAR1NA Occurrence: rare, mostly occurring individually, generally below 0.1% rel. ab. Number of species: perhaps up to 10 species, with 4 of them identified only partially. 36 ANNALES • Ser. hist. nat. • 13 • 2003 • 1 Sou» VRlSER: ME1013ENTHIC EAUNA tWIIHOUT HARPACTICOIPA) IN THE SOUTHERN PART OE GULF OF TRIESTE. SLOVENIA: LIST OF TAXA, 33-« INSECTA Some rare and in only at two localities found dipteral larvae (family Chironomidae) of unknown number of species. S1PUNCUL1DA A single and only partially determined individual. GASTROPODA Occurrence: common, although not massive, usually with a few individuals per sample. Altogether 0.30% rel. ab. Number of species: unknown, possibly over 100 species. Only 10 species partially identified. 8IVALVIA Occurrence: massive, even with a few dozen individuals per sample. Altogether 0.25% rel. ab. Number of species: unknown, possibly over 100 species, with only 9 partially determined. BRYOZOA Some rare individuals, 1 partially identified species. CHAETOGNATHA Two coincldentally caught planktonic individuals of the same species. HOLOTHURIOIDEA Some rare juvenile individuals, 3 partially identified species. ASTEROIDEA Some rare juvenile individuals, 1 identified species. OPHIUROIDEA Occurrence: ail over the research area, individual juveniles, only 1 species determined. ECHINOIDEA Some rare individual larvae of unknown number of species. ASC1DIACEA At the end of taxonomic survey of our meiofauna, a question might be raised, where to place, in view of its species diversity, the area researched, if looking at potentially similar parts of the near and far neighbourhood. No comparable surveys can unfortunately be traced, while any serious diversity evaluation of our data is rendered very difficult by at this moment still highly inadequate systematic extent of research into the dominant, abundant and species-rich groups, such as Nematoda, Oligochaeta, Nemertinea, Polychaeta, Gastropoda and Bivalvia. Much work is thus still waiting for the future taxonomists, for the species determinations carried so far have probably reached less than a third of their presumed total number. In spite of the stated taxonomic gaps, we could venture a judgment - on the very basis of the existing facts - that along with harpacticoid copepods {130 species) the fauna presented in this paper (180 species) also significantly contributes to the high diversity of our coastal waters. LIST OF SPECIES With the exception of harpacticoid copepods, the list presents all till now registered taxonomic groups of meiofauna in the area researched. They are arranged according to the already mentioned system, i.e. in compliance with the available degree of their systematic analysis. This, however, can be only at the level of the higher taxa (e.g. ordo, classis, subclassis, familia), or it is determined down to the level of genus and species. The different species within the same taxon are either indicated as undetermined number of species (spp.) or are differentiated and numbered (genus sp. 1, sp. 2, etc.). Complete species determinations were given where at all possible. FORAMINIFERA Ammonia beccarii (t.) - smooth Ammonia beccarii (L.) - ornamented Ammonia sp. 1 Cribroeiphiclium sp, 1 Eggereila advena Cushman Elpbidiurn crispurn (L.) Elpbidium sp. 1 Miiionella. sp. 1 Quinquelocuiina sp. 1 Rosaiina globularis d'Orbigny Sigmoilina cf. costata Schlumberger Triioculina laevigata d'Orbigny Trochammina inflata (Montagu) HYDROZOA Some rare larvae. Siphonohydra sp. 1 Halammohydra sp, 1 37 ANNALES ■ Ser, hist. naf. • 13 • 2003 • 1 Borat VRISER: MEIOBENTH1C FAUNA (WITHOUT HARPACTICOIDA) IN Halammohydra sp. 2 Pinushydra sp. 1 Psammohydra sp. 1 ANTHOZOA Anthipatharia gen. spp. TURBELI.ARIA Allostoma sp. 1 Convoluta convoluta Abi Id Nemertoderma spp. Diopisthoporus spp. Mecynostomum spp. Paraphartostoma spp. Plagiostomum sp. 1 NEMERTINEA l leteronemertini gen. spp. Hoplonemertini gen. spp. NEMATODA Cyatholaimus sp. 1 Desmoscolex sp. 1 Enoplus sp. 1 Euchromadora striata (Eberth) KINORHYNCHA Echinoderes sp. 1 Echinoderes sp. 2 Neocentrophyes sp. 1 Pycnophyes sp. 1 Pycnophyes sp. 2 Pycnophyes sp. 3 Trachydemus sp. 1 Trachydemus sp. 2 POLYCHAETA Aonides oxycephala (Sars) Aricidea spp. Brada viltosa (Rathke) Capitella capitata (Fabricius) Capitellidae gen. spp. Cirratulus filiformis (Keferstein) Cossura soyeri Laubter Dorvillea sp. 1 Euclymene palermitana (Grube) Eunice vittata {delle Chiaje) Hesionidae gen. spp. Hyalinoecia brementi Fauvel Lumbrineris gracilis (Ehlers) THE SOUTHERN PART Of GULP Of TRIESTE, SLOVENIA: LIST OF TAXA, 33-42 Lumbrineris spp. Magelona sp. 1 Maldane glebifex Grube Micronephtys sp, 1 Nereidae gen. sp. 1 Nereidae gen. sp. 2 Notomastus sp. 1 Notomastus sp. 2 Onuphis sp. 1 Owenia fusiformis delie Chiaje Paraonis lyra Southern Proxillella sp. 1 Proxillella sp. 2 Proxillella sp. 3 Prionospio cirrifera Wiren Prionospio malmgreni Claparede Sabellidae gen. spp. Scolelepis fuliginosa (Claparede) Sphaerosyllis sp. 1 Spionidae gen. spp. Spirorbinae gen, spp. Syllidae gen. sp, 1 Syilidae gen, sp, 2 Syllidae gen. sp, 3 Terebellides stroemi Sars OLIGOCHAETA Enhytraeidae gen. spp. OSTRACODA Callistocythere adriatlca Masoli Callistocythere sp. 1 Callistocythere sp. 2 Costa ed wards i (Roemer) Costa batei (Brady) Cythere antiquata Baird Cytheretta adriatica Ruggert Cytheridea neapo/j'iana Kolmann Hiltermannicythere túrbida (G.W.Müller) Loxoconha sp.1 Loxoconcha sp.2 Neocytherideis sp. 1 Neocytherideis sp. 2 Pterygocythereis jonesi (Baird) Sem/eyl/ierura sp. 1 Semicytherura sp. 2 CIRRIPEDIA Chthamalus sp. 1 DECAPODA Callianassa stebbingi Borra 38 ANNALES • Ser. hist. nat. -13- 2003 • 1 Boflil VRISER: MEiOSENTHiC EAUNA (WITHOUT HARI'ACTICOIDAJ IN THE50UTHERN PART OF GUI.F OF TRIFSTE.3LOyeNIA:l!St;ÖF-TAXA;33s«- Carcinus sp. 1 TANAIDACEA Crangon sp. 1 Lthusa mascarone Herbst Apseudes latreillei (Milne Edw.) - ■ Galathea sp. 1 Leptochelia savignyi (Kröyer) Hippolyte sp. 1 Tanais cavolinii Milne Edw. Macropodia longirostris (Fabricius) Palaemon sp. 1 LEPTOSTRACA Processa canaliculata ÍLeach) Sicyonia sp. 1 Nebalia bipes Fabr. AMPHIPODA ACARINA Ampelisca typica (Bate) Agauopsis brevipalpus Trousseart Ampelisca spinnipes Boeck Agauopsis sp. 1 Ampelisca sp. 1 Copidognathus sp. 1 Ampelisca sp. 2 Copidognathus sp. 2 Capreila sp. 1 Dexamine sp. 1 INSECTA Cammarus locusta (L.) Caminaras sp. 1 CHtronomidae gen. spp. Gammarus sp. 2 L ep idepec reu ms p. 1 SIPUNCULIDA Lysiana5sa sp. 1 ieucothoe sp. 1 Phascolosoma sp. 1 Phtisica marina Slabber Pseudoproteüa sp. 1 GASTROPODA l SOPO DA Bittium reticuiatum Da Costa Cerithium vulgatum Bruguiere An i lucra physodes (L.) Conus sp. 1 Arcturus sp. 1 Gibhula spp. Bopyrus squiltarum Latr. Haminea hydatis (L.) Cirolana borealis Lili. Monodonta spp. Cyathura carinata (Kr.) Nassa spp. Cymodoce truncata (Mont.) Opistobranchia spp. Üynamene sp. 1 Polyriices sp. 1 Gnathia sp. 1 Rissoa spp. Idotea bal tica (Paii.) Ligia italica Fabr. 81VALVIA L minoría sp. 1 Nerocilla sp. 1 Aloidis gibba (Olivi) Synisoma sp, 1 Cardio idea spp. Chlamys sp, 1 MYSIDACEA Gastrana fragilis (L.) Loripes lacteus (L.) Diamysis sp. 1 Macoma sp. 1 Mys/s sp. 1 Nucula sulcata (Bronn) Siriella clausiG. Sars Teliina pulchella Lamarck Siriella sp. 1 Venerupis sp. 1 CUMACEA BRYOZOA Cumella sp. 1 Aetidae gen. spp. Diastylis sp. 1 ßicellardiidae gen. spp. Iphinoe sp. 1 Monobryozoon gen. sp, 1 Leucon mediterráneas Sars 39 ANNALES • Ser. hist. nat. • 13 • 2003 • 1 Borut VRIŠERr MESOBENTHIC FAUNA [WITHOUT HARPAC.TSCOiFM) IN CHAETOCNATHA Spadella c.ephaloptera (Busch) HOLOTHLJRIOIDEA Holothuria sp. 1 Labidoplax sp. 1 Trachythyone sp. 1 ASÏEROIDEA Asterina gibbosa (Pennant) Astropecten sp. 1 THE SOUTHERN PART OF CUIF OF TRIESTE, SLOVENIA: LIST OF TAX A, 33-42 OPHiUROIDEA Amphipholis squamata (Delie Chiaje) Amphiura spp. Ophiothrix spp. ECU I NO IDEA Echinopluteus ■■ larvae ASCiDIACEA Perophora - larvae Clavelinidae - larvae MEIOBENTOŠKA FAVNA (BREZ HARPAKTIKOIDOV) JUŽNEGA DELA TRŽAŠKEGA ZALIVA: SEZNAM TAKSONOV Borut VRIŠER Nacionalni inštitut za biologijo, Morska biološka postaja, Si-6330 Piran, Fornače 41 E-maii: vriser@mbss.org POVZETEK Prispevek je dostej prvi poskus celovitejšega sistematskega pregleda bentoške meiofavne '(izvzeti so že predstavljeni Harpacticoida), pripravljenega na osnovi obsežnega gradiva, zbranega med številnimi raziskavami v zadnjih tridesetih let na območju južnega dela Tržaškega zaliva, ki danes pripada teritorialnim vodam republike Slovenije. Poudarek dela je na taksonomskem seznamu, ki obsega 30 večjih skupin s 180 popolnoma ali le delno determiniranimi vrstam/. Ključne besede: meiofavna, seznam vrst, Tržaški zaliv, Slovenija REFERENCES Bartsch, I. & T. M. Iliffe (1985): The halacarid fauna (Halacaridae, Acari) of Bermuda's caves. Stygologia, 1(3), 301-321. Bonaduce, G., G. Ciampo & M. Masolt (1975): Distribution of Ostracoda in the Adriatic sea. Repr. Pubbl. Staz. Zool. Napoli, 40, 1-304. Bouillon, J. & P. A. Grohmann (1990): Pinushydra chiquitita gen. et sp. nov. (Cnidaria, Hydrozoa, Athe-cata), a solitary marine mesopsammic polyp. Cah. Biol. Mar., 31, 291-305. Chevreux, E. & L. Fage (1925): Faune de France. 9. Amphipodes, Paul Lechevalier, Paris. 486 pp. De Mm, R. & E. Vio (1997): Moiluschi conchiferi del litorale sloveno. Annales Ser. hist, nat, 7(1), 241-258. 40 ANNALES • Ser. hist. nat. • 13 • 2003 ■ 1 bixiil vrišer: mei08enth1c fauna (without harpacticoida) in the southern part of culi" of trieste, slovenia: ust of taxa, 33-42 Gruner, H. E. (1965): Krebstiere oder Crustacea. V. iso-poda. tn: Dahl, F. (ed.): Die Tierweit Deutschlands, 51. G. Fischer Verl., jena. 371 pp. Grünspan, T. (1908): Beiträge zur Systematik der Gastrotrichen. Zoo!. Jahrb. Syst., 26(2), 214-254. Higgins, R. P. (1977): Two new species of Echt node ¡es (Kinorhyncha) from the South Carolina. Trans. Am. Mi-crosc. Soc., 96(3), 341-354. Hillings, N. C. (1971): Proceedings of the first international conference on meiofauna. Smithsonian Contr. Zoo!., 76, Washington, 126 pp. Hummon, W. D., M« A. Todaro, M, Balsamo & P. Ton-giorgi (1990): Effects of Pollution on marine Gastrotri-cha in the Northwestern Adriatic Sea. Mar. Pol!. Bull., 21(5), 241-243. Evans, W. A., M. A. Todaro & W. Hummon (1993): Eutrophication and Gastrotrich diversity in the Northern Adriatic Sea. Mar. Poll. Bull., 26(5), 268-272. Kararnan, G. S. (1972): On some new or very interesting Amphipoda of the Adriatic Sea. Mem. Mus. Civ. Stor. Nat. Verona, 20, 99-147. Karaman, G. S. (1973): Contribution to the knowledge of the Amphipoda, the Phoxocephalidae family of the Adriatic Sea. Glas, Republ, Zav. Zašt. Prir. - Prir, Muz. Titograd, 5, 47-101. Klie, W. (1938): Krebstiere oder Crustacea. ML Ostra-coda, Muschelkrebse. In: Dahl, F. (ed.): Die Tierwelt Deutschlands, 34. G. Fischer Verl., Jena, 230 pp. Marcotie, B. M. & B. C. Coull (1974): Pollution, diversity and melobenthic communities in the North Adriatic (Bay of Piran, Yugoslavia). Vie Milieu Ser. 8 Oceanogr., :24(2), 282-300. Meischner, D. & J. Rumohr (1974): A light-weight, high momentum gravity corer for subaqueous sediments. Senckenb. Marit., 6,105-116. Nords i eck, F. (1968): Die Europäischen Meeres Gehausseschnecken (Prosobranchia). G. Fischer Verl., ■Stuttgart, 273 pp. Nordsieck, F. (1969): Die Europaischen Meeres-:muscheln (Bivalvia). G. Fischer Verl., Stuttgart, 256 pp. Nordsieck, F. (1972): Die Europäischen Meeresschnecken (Opistobranchia mit Pyramide!! idae, Ris-soaceae). G. Fischer Verl., Stuttgart, 327 pp. Ogorelec, B,, M. Mišic & }. Faganeii (1991): Marine geology of the Gulf of Trieste (Northern Adriatic): Sedi-mentological aspects. Mar. Geo!., 99, 79-92. Piatt, H. M. & R. M. Warwick (1983): Free-living marine Nematodes. I. British enoplids. Cambridge Univ. Press, Cambridge, London, New York, New Roche!le, Melbourne, Sydney, 307 pp. Piatt, H. M. & R. M. Warwick (1988): Free-living marine Nematodes. II. British chromadorids. E.J. Bril! / Dr. W. Backhuys, Leiden, New York, Köbenhavn, Köln. 502 pp. Riedl, R. (1956): Zur Kenntnis der Turbellarien Adri-atischer Schlammböden sowie ihrer geographischen und faunistischen Beziehungen. Thalassia Jugosl., 1, 69-125. Riedl, R. (1983): Fauna und Flora des Mittelmeeres. Verl. Paul Parey, Hamburg, Berlin, 836 pp. Rieger, R. M. (1971): Die Turbellarienfamiiie Doiicho-macrostomidae RIEGER. II. Dolichomacrostominae I. Zoo!. Jb. Syst., 98, 569-703. Salvini-Plawen, L. von (1966): Zur Kenntnis der Cni-daria des nordadriatischen Mesopsammon. Ver-ff. Inst. Meeresforsch. Bremerhav., 2, 165-186. Salvini-Plawen, L. von (1968): Neue Formen im marinen Mesopsammon: Kamptozoa und Aculifera (nebst der für die Adria neuen Sandfauna). Ann. Nathist. Mus. Wien, 72, 231-272. Sars, G. O. (1896): An account of the Crustacea of Norway. II. Isopoda, Part I, II. Apseudidae, Tanaidae. Pubi, Bergen Museum, Bergen, 255 pp. Schrom, H. (1966a): Zur Kenntnis des Mesopsammales der Nordadria: II. Die Sande in der Umgebung von Rovi- gno und ihre Faunenmerkmale. Thalassia Jugosl., 4, 65- 79. Schrom, H. (1966b): Gastrotrichen aus Feinsanden der Umgebung von Venedig. Boll. Mus. Civ. Stor. Nat. Ve-nezia, 17, 31-44. Schrom, H. (1966c): Verteilung einiger Gastrotrichen im oberen Eulitoral eines nordadriatischen Sandstrandes. VerOff. Inst. Meeresforsch. Bremerhav., 2, 95-104. Sterrer, W. (1965): Cnathostomula axi Kirsteuer und Austrognathia (ein weiteres gnathostomuliden - genus) aus der Nordadria. Z. Morph. Ökol. Tiere, 55, 783-795. Sterrer, W. (1967): Beiträge zur Kenntnis der Gnathos-tomulida. I. Anatomie und Morphologie des Genus Pterognathia Sterrer. Arkiv för Zoologi, 22(1), 1-125. Vrišer, B. (1979): Modifikacije meiofavne v umetno poluiranem lagunarnem ekosistemu. Biol. vestn., 27(1), 75-86. Vrišer, B. (1982): Strukturne in bioprodukcijske značilnosti meiofavne v čistem in umetno onesnaženem okolju Strunjanske lagune. Acta Adriat., 23(1/2), 339-353. Vrišer, B. (1983-84): Meiofaunat community structure and species diversity in the Bays of Koper, Strunjan and Piran (Gulf of Triest, North Adriatic). Nova Thalassia, 6, 5-17. Vrišer, B. (1986): Vpliv organskega onesnaženja na meiofavno priobalnih glinastih muljev Koprskega zaliva. Biol. vestn., 34(2), 93-104. Vrišer, B. (1989): Meiofavna južnega dela Tržaškega zaliva. I. Taksonomska struktura in abundanca. Biol. vestn., 37(4), 65-76. Vrišer, B. (1991): Meiofauna of the southern part of the Gulf of Trieste (Northern Adriatic) II. Problems of the me-soscale spatial distribution. Biol, vestn., 39(1), 165-176. Vrišer, B. (1992): Meiofavna južnega dela Tržaškega zaliva, ill. Favna in združbe harpaktikoidov (Copepoda: Harpacticoida). Biol. vestn., 40(2), 89-106. Vrišer, B. (1996): Sezonska dinamika in variabilnost harpaktikoidov (Copepoda : Harpacticoida) v Tržaškem 41 ANNALES • Ser. hist. nat. • 13 • 2003 • 1 Borif! VRISSR: MEfQSENTHSC FAUNA {WITHOUT HARPACTICOIDA) in THE SOUTHERN PART OF GULF OF TRIESTE, SIOVENIA: UST OE TAXA. 33-42 zaiivu: trüetna raziskava. Annaies Ser. hist, nat., 6(1), 53-60. Vriser, B. (1997): Seasonal and three-year variability of meiofauna in the Gulf of Trieste (Northern Adriatic). Period. bioL, 99(2), 209-212. VriSer, B. (1998): Meiofauna! recolonization of defau-nated sediments: a field experiment; preliminary results. Period, bio!., 100(1), 63-69. Vriser, B. (1999): Meiofavna Strunjanskega zaliva 18 let pozneje: ponovljena raziskava. Anuales Ser. hist, nat., 9(2), 209-212. Vriser, B. (2000a): Meiobenthic Harpacticoida (Cope-poda) from the southern part of the Gulf of Trieste (northern Adriatic). I. List of taxa. Annaies Ser. hist, nat, 10(1), 23-38. Vriser, B. (2000b): Meiobenthic Harpacticoida (Cope-poria) from the southern part of the Gulf of Trieste {northern Adriatic). II. Ecology and spatial distribution. Annaies Ser. hist, nat., 10(1), 39-53. Vriser, B. (2001): Meiofavna izolske iuke pred graditvijo marine in po njej: ponovljena raziskava - preliminarni rezultati. Annaies Ser. hist, nat., 1 1(1), 75-78. Vriser, B. (2002): The meiofauna of two protected shallow biotopes on the Slovene coast: the Škocjan inlet and the Strunjan lagoon. Anuales Ser. hist, nat., 12(2), 203-210. Vrišer, B. & A. Vukovič (1999): Seasonal and long-term variability of meiofauna in the environment, frequently affected by hypoxia in central part of the Gulf of Trieste. Annaies Ser. hist, nat, 9(2), 203-208. Vrišer, B. & A. Vukovič (2000): Meiofauna! recolonization of defaunated sediments: tl. Harpacticoida (Cope-poda); preliminary results. Period, bio!., 102(2), 201-206. Wieser, W. (1960): Benthic studies in Buzzards Bay. II. The meiofauna. Limnoi. Oceanogr., 5, 121-137. 42 ANNALES • Ser. hist, nat. • 13 • 2003 • 1 original scientific article UDK 595.3:575.17(262-191.2) received: 2003-01-05 ENZYMATIC VARIABILITY OF MEDITERRANEAN SLIPPER LOBSTERS, SCYLLARIDES LATUS, FROM SICILIAN WATERS Marco L. ß IANCHI NI CNR and Sot. Porto Romano, S-Rome, Piazza P. Paoli 3 f':'-maii: imarboE@mciink.it Ehud SPANIER Leon Recarrati Institute for Maritime Studies, University of Haifa, IL-31905 Haifa, Mount Carmei Sergio RAGONESE 1st. ricerche Risorse Marine e ¡'Ambiente, IRMA/CNR, 1-91026 Mazara del Vallo (TP), Via Luigi Vaccara 61 ABSTRACT A genetic comparison of slipper lobsters, Scyliarides latus, from different areas in Sicily was carried out; electro-phoretically checking 22 enzymatic activity zones. The analysis has shown a low degree of variability among the specimens; therefore, non-local breeders might be used for restocking without harming the biodiversity. Key words: Crustacea, Decapoda, Scyllaridae, Scyliarides, genetics, electrophoresis VARIABILITA ENZiMATICA NELLA MAGNOSA MEDiTERRANEA, SCYLLARIDES LATUS, Dl ACQUE SSCILIANE SINTESI L'articolo presenta il confronto genetico tra magnose fScyllarides latus/ provenienti da diverse aree siciliane, confronto effettuato con il controllo elettroforetico di 22 zone di attivita enzimatica. L'analisi ha evidenziato un basso grado di variability tra gli individui, pertanto gli autori ipotizzano che esemplari allevali in altre localita po-trebbero venirusati nel ripopolamento, evitando efletti negativi sulla biodiversita. Parole chiave: Crustacea, Decapoda, Scyllaridae, Scyliarides, genetica, elettroforesi 43 ANNALES • Ser. hist. riat. • 13 • 2003 ■ 1 Marro L BIANCHINI el al.: ENZYMATIC VARIABILITY Of MEDITERRANEAN SLIPPER LOBSTERS, SCYLlAftlOES LATUS. FROM SICILIAN WATERS, «-SO INTRODUCTION On the Sicilian coasts, restocking of the now rare Mediterranean slipper lobster, Scyllarides talus, could achieve stable results, since the decline of the resource seems due to a shortage in recruitment, not to environmental degradation {Bianchini eta/,, 1998), Of course, a soLind enhancement program should operate without disrupting the existing equilibrium. To preserve the biological diversity, and to reduce the risks related to the introduction in the genetic pool of characteristics different from the local ones, it is necessary to make sure that brooders and seeding animals belong to the autochthonous population, or that their origin is genetically similar. With this in mind, morphological (Bianchini eta/., 1996) and karyological (Deiana et at., 1997) studies may be used for screening, together with genetic analyses, based on PCR methods or on electrophoretic techniques. This last approach is based on the notion that proteins under the effect of an electric field migrate along the medium in accordance to their net charge and their molecular weight; utilizing this phenomenon, the electrophoresis displays molecular differences due to ami-noacidic substitutions or deletions. In fact, these differences arise from nucleotide mutations at DNA level of the structural gene, which produce isozymes (Hunter & Markert, 1957) migrating at different velocities. The isozymes, i.e. the multiple forms that an enzyme could as- sume, may depend on the presence of more than one locus codifying the enzyme (allozymes, following Pra-kash et at., 1969), or on the effect of post-translational modifications on the formed polypeptic chains (Richardson et at., 1986); a locus is considered polymorphic when the frequency of the most common allele is lower than 95%. The last step in the analysis of enzymatic polymorphisms is the interpretation of the observed electrophoretic pattern, which requires special care in case of species not extensively studied (Richardson et at., 1986). MATERIALS AND METHODS Thirty-three Mediterranean slipper lobsters, Scyl-larides latus, coming from different Sicilian areas (Fig. 1) were examined; their morphometric data are given in Table 1. The electrophoretic runs were commissioned to an external University laboratory, using funds provided by a national program on slipper lobster restocking (III triennial plan of the former Ministry of Merchant Marine). Pereiopod muscles were used; samples were transported in liquid N2 to the laboratory, where they were manLially homogenized in water, centrifuged at 3000 rpm for 30 min, and stored at -70 "C. The methodology used to study the Scy Ha rides latus population was the electrophoretic analysis of the enzymatic polymorphisms. Lower Tyrrhenian \ i é ¿.Trapani al ermo J" X fyMéskma / ; X J V"- / S-«., J Agrigento T Catania Ionian Sea '.J'-->. \ V X «¡A? ¿■iv S 'f i x Strait of Sicily Fig. 1: Areas of collection (crosses) of the Sicilian "population" of slipper lobster (Scyllarides latus). Fig. 1: Območja zbiranja (križci) sictlijanske "populacije" velikega nagajivca (Scyüarides latus). 44 ANNALES • Ser. hist. riat. • 13 • 2003 ■ 1 Marco L. BIANCH1N1 el si.: ENZYMATIC VARIABILITY OF MEDITERRANEAN SLIPPER LOBSTERS, $CYU.ARIDES LATUS, FROM SICILIAN WATEKS^ÏÎ 50 Cel ¡ogel (cellulose acetate) was used as support; the electrophoretic runs were performed in Chemetron tanks filled with 250 ml of bridge buffer, holding 3 cel toge! stripes (5.7x14 cm), pre-soaked for 15 min in a gel buffer eqLial to that of the run ("continuous buffer"). Each celloge! strip carried 5 samples; to allow comparison, the last sample of each strip was repeated on the next one. At the end of the run, every strip was coloured with techniques specific for each enzyme, using buffered solutions with substrates, coenzymes and/or coupled enzymes and colours that bond with the final products. A thermostat was used for the enzymatic reaction; once the colour appeared, the reaction was stopped immersing the ceilogel stripes in acetic acid (10%), and the stripes were sealed and kept at 4 'C. Twenty enzymatic sets, accounting for 22 independently variable activity zones, i.e. accounted as the product of 22 loci, were examined. Table 2 reports the tested enzymes, their abbreviations, and the number of interpreted loci; the allele designation follows the numeric system based on the relative gel mobility of isozymes. Table 3 reports, for each tested enzyme, the run conditions (buffers, times, applied tension in Volt, electrical input in mA, depending on the buffer ionic strength) and the colouring techniques, as well as the respective bibliographic references. Tab. 1: Morphometric characteristics of the slipper lobsters (Scyllarides latus) analysed eiectrophoretically by sex (F - female> M = male). Tab. 1: Morfometrične značilnosti velikih nagajivcev (Scyllarides latus), analizirane elektroforetlčno po spolu (F = moški, M = ženske). The Sicilian slipper lobsters show a very modest electrophoretic variability in the 22 examined loci (Tab. 4): 20 loci are completely, or almost completely, fixed in the same allele, and the polymorphism is low in the other 2 loci (IDH and MDH-2) too. Table 5 reports the estimates of the populattonafgenetic variability, expressed as mean number of alleles per locus (N0), percent of polymorphic loci (p), observed (H0) and expected (HJ heterozygosity (Nei, 1978). The studied population presents low values of polymorphism, with Ho=0.020, Hj=0.019, mean number of alleles per locus equal to 1.2 and percent of polymorphic loci equal to 9.1. Moreover, the observed genotypic frequencies were compared with the expected frequencies, to display possible divergences from the Hardy-Weinberg equilibrium, per population and per locus (Tab. 6). Using the ~¡C analysis, the studied Sicilian population of 5. latus results in substantial equilibrium in all the examined loci. Tab. 2: Enzymatic systems analysed eiectrophoretically in the slipper lobster (Scyllarides latus). Tab. 2: Elektroforetlčno analizirani encimatski sistemi velikega nagajivca (Scyllarides latus). enzyme (Enzyme Commission number) abbreviation No. of loci Alcohol dehydrogenase (1.1.1.1) ADM 1 Adenilate chinase (2.7.4.3) ADK 1 Aldolase (4.1.2.13) ALDO 1 Creatine chinase (2.7.3.2) CK 1 Esterase (3.1.1.1) EST 1 Fructose-1 ,G-diphosphatase (3.1.3.11) FDP 1 Fumarase (4,2.1.2) FUM 2 Glyceraldehyde-3-phosphate dehydrogenase (1.2.1.12) GAPD 1 Glucose-phosphate isomerase (5.3.1.9) GPI 1 Esochinase (2.7.1.1) HK 1 Isocitrate dehydrogenase (1.1.1.42) IDH 1 Lactate dehydrogenase (1.1.1.27) LDH 1 Ma late dehydrogenase (1.1.1.37) MDH 2 Malic enzyme (1.1.1.40) me 1 Mannose-phosphate isomerase (5.3.1.8) MP! 1 Amino-peptidase (3.4.11) PEP 1 6-Phosphogluconate dehydrogenase (1.1.1.44) 6PGD 1 Phosphoglucomutase (2.7.5.1) Tgm 1 Trioso-phosphate isomerase tp! 1 (5.3.1.1) Xantine dehydrogenase (1.2.1.37) XDH 1 Total number of analyzed enzymes - 20 Total number of interpreted loci = 22 45 f M number 13 20 weight (g) mean 440.6 361.7 SD 191.0 76.7 min 258.0 237,0 max 940.0 523.0 carapace length (mm) mean 100.4 94.8 SD 13.2 7.0 min 88.6 81.7 max 132.2 106.7 RESULTS ANNALES • Ser. hist, nat. • 13 • 2003 • 1 Marco L. BSANCHiNi el a!.: ENZYMATjC VARIABILITY OF MEDITERRANEAN SLIPPER S..08STER5, SCYUARIOtS LAWS. FROM SICILIAN WATERS, 43-50 Tab. 3: Electrophoretic methods used for separation of the slipper lobster (Scyllarides latus) samples. Tab. 3: Elektroforetične metode, uporabljene za ločevanje primerkov velikega nagajivca (Scyllarides latus). enzyme buffer (conc.) Volt/hour/mA coloring technique (reference) ADH C (1 x) 160/2:00/10 Richardson etal., 1986 ADK B (2 x) 160/2:30/18 Richardson etal., 1986 ALDO TEC 0.075 (1x) 160/2:00/14 Harris & Hopkinson, 1976 CK C(2x) 160/2:00/18 Richardson et ai, 1986 EST G (1 x) 160/1:00/18 Richardson etal., 1986 FDP B (1x) 160/2:00/10 Richardson et at, 1986 FUM A (2x) 160/1:30/8 Richardson etal., 1986 GAPD C (1 x) 160/2:00/10 Richardson eta/., 1986 GPI C (1x) 160/2:00/10 Richardson et a/., 1986 HK C (1 x) 160/1:15/10 Richardson etal., 1986 IDH A (1x) 160/1:45/10 Ayala etal., 1972 LDH BOx) 160/1:45/10 Selander etal., 1971 MDH C Ox) 160/1:30/10 Richardson etal., 1986 ME B Ox) 160/1:30/10 Richardson etal., 1986 MPI B Ox) 160/1:0Q/10 Richardson etal., 1986 PEP A (2x) 160/1:45/8 Richardson etal., 1986 6PGD B Ox) 160/1:30/10 Richardson etal., 1986 PGM C Ox) 160/1:45/8 Richardson etal, 1986 TPI B Ox) 160/2:00/10 Richardson etal., 1986 XDH F (1x) 160/1:45/18 Richardson etal., 1986 Bibliographic references for the buffers: A, B, C, F, G: Richardson ef a/., 1986 TEC 0.075: Meera Khan, 1971 DISCUSSION The electrophoretic analysis of the enzymatic: polymorphisms has shown low levels of variability in the Sicilian population of Scyllarides latus. This result should not be interpreted as a bottleneck effect of the numerical scarcity of the Sicilian population, but may be structural to the taxon (Hardwick & Cline, 1984, 1985, 1986). In fact, preliminary unpublished results on two other populations, from Israel and from the Azores, seem to confirm a minimal heterozygosity. Moreover, this lack of genetic diversity is in substantial agreement with the pattern observed in other species of large-size decapod crustaceans (Hedgecock, 1987). On the other hand, the apparent resemblance of the slipper lobster samples could be linked to peculiar variability patterns of the gene-enzyme systems hitherto tested; other kind of loci might display higher levels of variation. The genetic analyses have shown a high similitude among the studied animals, coming from distant geographical locations: this fact suggests that non-local specimens could be used, as breeders or seeding stuff, in restocking and stock enhancement programs in impoverished areas, without exorbitant risks of genetic contamination and biodiversity reduction. Nevertheless, the seemingly genetic homogeneity of the Mediterranean slipper lobsters needs further testing, perhaps with more sophisticated techniques (e.g. the analysis of microsateilite loci), before the actual introduction of allochthonous material. CONCLUSIONS On the Sicilian coasts, restocking of the now rare Mediterranean slipper lobster, Scyllarides latus, could achieve stable results, since the decline of the resource seems due to a shortage in recruitment, not to environmental degradation. To preserve the biodiversity, and to reduce the risks related to the introduction in the genetic pool of characteristics different from the local ones, it is necessary to make sure that brooders and seeding animals belong to the autochthonous population, or that their origin is genetically similar. With this in mind, a genetic comparison of slipper lobsters, Scyllarides latus, from different areas in Sicily was carried out, electrophoretically checking 22 enzymatic activity zones (ADH, ADK, ALDO, CK, EST, FDP, FUM-1, FUM-2, GAPD, GPI, HK, IDH, LDH, MDH-1, MDH-2, ME, MPI, PEP-2, 6PGD, PGM, TPi, XDH). 46 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 Marco L 8MNCHSIMI el al.: ENZYMATIC VARI A8ILITY OF MEDITERRANEAN SUPPER LOBSTERS, SCYLLARIDES LATUS, FROM SICILIAN WATERS, 43-SO Tab. 4: Frequencies of alleles for 22 loci in the Sicilian population of slipper lobster (Scyllarides latus). Legend: N -number of specimens; A = most common/only allele; B - second allele. Tab. 4: Frekvence alel za 22 lokacij sicilijanske populacije velikega nagajivca (Scyllarides latus). Legenda: N - št. primerkov; A = najpogostejši/edini alel; B - drugi alel. llnrUS [ÄÖH [n- 29 [Ä 1.000 fÄDK n 24 !A 1.000 1 ALDO In 29 IÄ" 1.000 l jčk in" 24 [A 1.000 ¡EST [n 29 A 0.983 B 0.017 FDP n 27 A 1.000 FUM-1 n 29 :A 1.000 I FUM-2 n 29 A 0.983 B 0.017 GAPD n 29 A 1.000 GPf n 29 A 1.000 HK n 29 A 1.000 locus IDH N 29 A 0.948 8 0.052 LDH N 29 A 1.000 MDH-1 N 29 A 0.983 B 0.017 MDH-2 N 29 A 0.879 B 0.121 ME iN 29 ¡A 1.000 MP1 N 29 A 1.000 PEP-2 N 29 A 1.000 6PGD N 29 A 1.000 PCM N 29 A 1.000 TPI N 29 A 1.000 XDH N 29 A 1.000 Tab. 5: Cenetic variability estimates (± standard error) for 22 loci in the Sicilian population of slipper lobster (Scyllarides latus). Tab. 5: Ocene genetske variabilnosti (± standardna napaka) za 22 lokacij sicilijanske populacije velikega nagajivca (Scyllarides latus). mean No. ind./popuiat. (± SD) mean No. ai-leles/locus (NJ % polymorphic loci (p) mean heterozygosis (± SD) J observed (H„) j expected (Hj j 28.5 (0.3) 1.2 (0.1) 9.1 0.020(0.012) j 0.019(0.011) 47 ANNALES • Ser. hist. »at. • 13 • 2003 • 1 Marco L BSANCHINI & si: ENZYMATIC VARIABILITY Of MEDITERRANEAN SUPPfR I OBSTERS, SQ'UAfflDCS M TUS. FROM SICILIAN WATERS, 43-50 Tab. 6; test for the rejection of the Hardy-Weinberg equilibrium in the Sicilian population of slipper lobster (Scyllarides latus). Tab. 6: Test % za zavrnitev Hardy-Weinbergovega ravnovesja v sicilijanski populaciji velikega nagajivca (Scyllarides latus). locus/class observed expected 9 X d.o.f. P EST 0.000 1 1.000 A-A 28 28.000 A-B 1 1.000 B-B 0 0.000 FVJM-2 0.000 1 1.000 A-A 28 28.000 A-B 1 1.000 B-B 0 0.000 IDH 0,057 1 0.812 A-A 26 26.053 A-B 3 2.895 B-B 0 0.053 |mdh-i 0.000 1 1.000 A-A 28 28.000 A-B 1 1.000 B-B 0 0.000 MDH-2 0.461 1 0.497 A-A 22 22.368 A-B 7 6.263 B-B 0 0.368 The Sicilian slipper lobsters show a very modest electrophoretic variability in the examined loci. 20 loci are completely, or almost completely, fixed in the same allele, and the polymorphism is low in tine other 2 loci (IDH and MDH-2) too. The observed heterozygosity (HJ equals 0.020, and the expected heterozygosity (Ha) equals 0.019, the mean number of alleles per locus (Na) is 1.2 and the percent of polymorphic loci is 9.1. Moreover, using the y? analysis, the studied Sicilian population of S. latus results in substantial equilibrium in all the examined loci. In fact, this lack of genetic diversity is in substantial agreement with the pattern observed in other species of large-size decapod crustaceans. The genetic analyses have shown a high similitude among the studied animals, coming from distant geographical locations: this result suggests that non-local specimens could be used, as breeders or seeding stuff, in restocking and stock enhancement programs in impoverished areas, without exorbitant risks of genetic contamination and biodiversity reduction. 48 ANNALES • Ser. hist, nat, ■ 13 • 2003 • 1 — Marco ! .. 8UNCH1N! el ah ENZYMATIC VARIABILITY OF MEDITERRANEAN SURF'S LOBSTERS, SCVUAKlOFS I :\TUS, FROM SICILIAN WATERS, 43-50 ENCtMATSKA VARIABILNOST VELIKEGA NAGAJIVCA, SCYLLARIDES LATUS, V SICiLIJANSKiH VODAH Marco/... BIANCHINI CNR and Soc, Porto Romano, i-Rome, Piazza P. Paoli 3 E-mail: imarbot@mclink.it Ehud SPAN1ER Leon Recanati Institute for Maritime Studies, University of Haifa, 11-31905 Haifa, Mount Carine! Sergio RAGONESE 1st. ricerche Risorse Marine e I'Ambiente, IRM A/CNR, i-91026 Mazara del Valio (TP), Via Luigi Vaccara 61 POVZETEK V sicilijanskih obalnih vodah bi z vlaganjem zdaj redkega velikega nagajivca, Scyllarides latus, dosegli bržkone dobre rezu/tate, saj vse kaže, da upadanja njegove populacije ne gre pripisati degradaciji tega morskega okolja. Toda da bi ohranili biodiverziteto v teh vodah in hkrati zmanjšali tveganja, povezana z vlaganjem osebkov v genetski "pool" z značilnostmi, ki se razlikujejo od lokalnih, bi bilo treba zagotoviti, da osebki za razplod teh rakov pripadajo avtohtoni populaciji, ali pa da je njihov izvor genetsko podoben lokalnemu. V ta namen smo opravili genetske primerjave med velikimi nagajivci, Scyllarides latus, iz različnih območij si-cilijanskih obalnih voda z elektroforetičnim pregledovanjem 22 encimatskih con aktivnosti (ADhi, ADK, ALDO, CK, EST, EDP, FUM-1, FUM-2, CAPO, GPI, HK, IDH, LDH, MDH-1, MDH-2, ME, MPl, PEP-2, 6PGD, PGM, TPI, XDH). Na raziskanih lokalitetah je bila ugotovljena zelo skromna elektroforetična variabilnost velikih nagajivcev. 20 lokaiitet je docela, ali skoraj docela, ustaljenih v istem alelu, polimorfizem pa je nizek tudi v dveh preostalih lokacijah (IDH in MDH-2). Opazovana heterozigotnost (Hj je bila 0,020, pričakovana heterozigotnost (HJ 0,019, srednje število alel na lokal iteto (NJ 1,2 in odstotek polimorfične lokalitete 9,1. Poleg tega smo z analizo ugotovili, da je preučevana sicilijanska populacija velikega nagajivca v precejšnjem ravnovesju na vseh pregledanih lokacijah. Pravzaprav se to pomanjkanje genetske pestrosti v precejšnji meri ujema z vzorcem, opaženim pri drugih vrstah velikih dekapodnih rakov. Genetske analize so pokazale veliko podobnost med preučevanimi živalmi z oddaljenih geografskih lokacij, kar daje misliti, da bi za razplod in povečanje populacije v teh osiromašenih vodah lahko uporabili oseMe iz drugih voda, in to brez večjih tveganj za genetsko "kontaminacijo" in zmanjšano biodiverziteto v si-cilijanskih obalnih vodah. Ključne besede: Crustacea, Decapoda, Scyilartdae, Scyllarides, genetika, elektroforeza REFERENCES Ayafa, F. J.,}. R, Powefl, M. L. Tracey, C. A. Mourao & S. Perez-Saias (1972): Enzyme variability in the Droso-phila willistoni group. IV. Genie variation in natural populations of Drosophila willistoni. Genetics, 70, 113-139. Bianchini, M. L., L. Chessa, S. Greco, S. Ragonese & G. Scarpelli (1996): Morphometry aspects of slipper lobster, Scyllarides latus. Proc. VI. Coll. Crustacea Decapoda Medit. 12-15 September 1996, Firenze, Italy. Bianchini, M. L., S. Greco & S. Ragonese (1998): II pro-getto "Valutazione del la fattibilith e potenzialitis del ri- popolamento attivo per la magnosa, Scyllarides latus (Crostacei Decapodi)": sintesi e risultati. Biol. Mar. Medit., 5(3), 1277-1283. Deiana, A. M., M. L. Bianchini, E. Coiuccia, A. Milia, R. Cannas, D. Serran & S. Salvadori (1997): Dati preliminary sulla cariologia del la magnosa (Scyllarides latus, Crustacea, Decapoda). Biol. Mar. Medit., 4(1), 640-642. Hardwick, C. W. Jr. & G. B. Cline (1984): Genetic characterization of a population of Scyllarides nodifer using isoelectric focusing (IEF) on some gene products, j. Ala. Acad. Sci., 55, 140-162. Hardwick, C. W. Jr. & G. B. Cline (1985): Differences in isoelectric focusing and eiectrophoretic mobility of iso- 49 ANNALES • Ser. hist nat. ■ 13 - 2003 • 1 Marco L. BSANCHINI e! ai: ENZYMATIC VARIABILITY OF MEDITERRANEAN SLIPPER LOBSTERS. SCYUARIOtS LATUS, f ROM SICILIAN WATERS, 43-50 zymes and proteins in tissue extracts of the slipper lobster Scyllarides nodifer (Stimpson). Isozyme Bull., 18, 53-55. Hardwick, C. W. jr. & G. B, Cline (1986): Isozymic analysis of the slipper lobster Scy liar ides nodifer (Stimpson) from the northern Gulf of Mexico, isozyme Bull., 19, 34-35. Harris, H. & D. A. Hopkinson (1976): Handbook of enzyme electrophoresis in human genetics. North Holland Publ. Co., Amsterdam, 374 pp. Hedgecock, D. (1987); Population genetic bases for improving cultured crustaceans. Proc. World Symp. Selection, Hybridization, Genetic Engineering in Aquaculture, Vol. 1, Berlin. Hunter, R. L. & C. L, Marker! (1957): Histochemical demonstration of enzymes separated by zone electrophoresis in starch gel. Science, 125, 1294-1295. Meera Khan, P. (1971): Enzyme electrophoresis on cellulose acetate gel: zymogram patterns in man-mouse and man-Chinese hamster somatic cell hybrids. Arch. Biochem. Biophys., 145,470-483. Nei, M. (1978): Estimation of average heterozygosity and genetic distance from a small number of individuals. Genetics, 89, 583-590. Prakash, S., R. C. lewontin & J. L. Hubby (1969): A molecular approach to the study of genie heterozygosity in natural populations. IV. Patterns of genie variation in central, marginal and isolated populations of Drosophila pseudo-obscura. Genetics, 61, 841-858. Richardson, B. P. R. Baverstock & M. Adams (1986): Allozyme electrophoresis: a handbook for animal sys-tematics and population studies. Academic Press, Sydney, Orlando. Seiander, R. K., M. H. Smith, S. Y. Yang, W. E. Johnson & J. B. Gentry (1971): Biochemical polymorphism and systematic« in the genus Peromyscus. I. Variations in the old-field mouse {Peromyscus polionotus). In: Studies in genetics. Vol. VI. Univ. Texas Publ. 7103, 49-90. 50 ANNALES • Ser. hist, nat. • 13 • 2003 • 1 short scientific article . . UDK 599.51(262.3) received: 2003-06-30 FIRST RECORD OF THE HUMPBACK WHALE, MEGAPTERA NOVAEANCUAE (BOROWSKI, 1 781), FROM THE ADRIATIC SEA Marco AFFRONTE, Leandro Augusto STANZAN1 & Giacomo STANZANi Fondazione Cetacea Onlus, [-47838 Riccione (RNÍ, Via Milano 63 E-mail: ambientemace@fondazionecetacea.org ABSTRACT Only five records of humpback whale Megaptera novaeangliae (Borowski, 1781} have been reported from the entire Mediterranean Sea, but none from the Adriatic. Here we report on a 90-minute sighting of a 9-W m long specimen in the central Adriatic in August 2002, Key words: Megaptera novaeangliae, humpback whale, first record, Adriatic Sea PRIMA SEGNALAZIONE DI MEGATTERA MEGAPTERA NOVAEANGLIAE (BOROWSKI, 1781) IN MARE ADRIATICO SINTESt Per il mare Mediterráneo sonó note solo cinque segnalazioni di megattera Megaptera novaeangliae (Borowski, 1781), fino ad oggi nessuna delle quali in Adriático. L'articolo riporta l'avvistamento durato novanta minuti di un esemplare di megattera di 9-10 metri, in Adriático centrale. Parole chiave: Megaptera novaeangliae, megattera, primo avvistamento, mare Adriático 51 ANNALES • Ser. hist nat. • 13 • 2003 • 1 Marco AfTRON'TE el si.: FIRST RECORD OF THE HUMPBACK WHALE. Mr CAP ICR A NOVACANCLIAE (BOROWm, 17151!, FROM THE ADRIATIC SEA. SI-54 INTRODUCTION Humpback whales Megaptera novaeangliae (Borow-ski, 1781) are distributed in all oceans, ranging from tropical wintering grounds along the islands and continental coasts to the edges of polar ice zones in summer. In the eastern North Atlantic they overwinter around the Cape Verde Islands and off northwest Africa. These stocks spend summer from New England to southeastern Baffin Island, along the western coast of Greenland, north to Disko Bay, around Iceland and around Norway. The summer migration of the Cape Verde population northward is still poorly documented {teatherwood & Reeves, 1983). Htimpback whales are seen around Cape Verde Islands from December until june. if the migration from Cape Verde northward really exists, it should therefore start from May (jann & Wenzel, 2001; Jann et. ai., in press). The relationships between the animals in Cape Verde and those wintering in the West Indies remain unknown. But the analysis of luimpback songs from the Cape Verde Islands and the West Indies suggests a possible exchange of animals between these feeding grounds (Winn & Winn, 1978). No documented population of humpback whales exists in the Mediterranean, where the specimens observed were certainly vagrants from the eastern North Atlantic population. On!y five records have been reported for the entire Mediterranean Sea: a young specimen captured near Toulon (France) in 1885; two specimens sighted and photographed in 1986 north of Minorca (Balearic Islands, Spain); a juvenile in the Gulf of Gabes (Tunisia) in 1992, and a young specimen incidentally captured near Cavalaire (France) in 1993 (Notarbartolo di Sciara, 2002). !ri April 2001, a humpback whale, measuring about 10-11 m in length and seemingly in good health, was seen breaching in the Argolic Gulf near Tolos (Greece), about 55 miles southwest of Athens. Video footage was presented during the 15,h European Cetacean Society Meeting held in Rome in May 2001. Additional records are currently in press by Frantzis and colleagues (Frantzis etal., in press). In this paper we report the first record of Megaptera novaeangliae in the Adriatic Sea and the Italian waters. MATERIALS AND METHODS The Adriatic, basin is part of the Mediterranean Sea, linked to its central part through the Strait of Otranto. The bottom is mainly sandy or muddy. It is a warm sea with a mean temperature almost always above 11-12 °C The shallow northern basin is cooler in winter, reaching 6-8 *C, and warmer in summer, when the surface temperature can reach 26-28 *C The salinity shows great oscillations and the coastal water can be greenish due to f ^¿fe Fig. I: The humpback whale's back appeared skinny, with vertebra protruding. (Photo: C. Stanzani) SI. 1: Osebkov hrbet se je zdel mršav z močno poudarjenimi hrbteničnimi vretenci. (Foto: G. Stanzani) the high concentration of phytoplankton. After heavy rains it can take on a yellow color (Buljan & Zore-Armanda, 1976). As part of the national network of Centra Studi Ceta-cei, Fondazione Cetacea is working on marine mammals in the northern Adriatic Sea, Within this framework, the Fondazione Cetacea began, in 1993, the "Onde dai Mare" (Waves from the sea) project, whose purpose is to increase the awareness about cetacean species living in Italian waters. This is done through education and active participation of all persons either working at sea (fishermen or sailors) or vacationing there. The project consists of a network of "calling centers" usually located in marine protected areas, aquaria or other facilities able to contact a large number of people. RESULTS AND DISCUSSION On 4 August, 2002, at 13:00 h, the Pesaro Coast Guard reported a sighting of a "big cetacean" off the Fano coast (43*50' N, 13*02' E). Three hours later, the specimen was sighted again by a sports boat, only 150 meters off the coast of Senigallia (4.3U45' N, 13*15' E). The Fondazione Cetacea group reached the animal, with the help of Protezione Civile Numana and Monte Conero diving center of Numana, at about 18:00 h. In the meantime it had moved about 2 miles off. The very long, almost completely white flippers and the typical knobs on the head and on the leading edge of the flippers allowed us to identify it as a humpback whale. It was about 9-10 m in total length. We followed the specimen for about 1.5 hrs, in good sea, wind and visibility conditions. During the entire sighting, the humpback whale was moving steadily southward without notable deviation. Many photographs and a video were taken (Figs. 1 and 2). 52 ANNALES • Ser. hist, nat. • 13 • 2003 • 1 -Marco A [FRONTE er jJ.: RRST RECORD OF THE HUMPBACK WHAI.E, MiCAPTFRA NOVAliANCUAt: (BOROWSKf. 1 78 U, FROM THE ADRIATIC SEA, 51-54 Fig. 2: The very long and white flippers are amongst the most recognizable features of the humpback whale. (Photo: G. Stanzani) Fig. 2: Zelo dolge, bele prsne plavuti so med najbolj opaznimi značilnostmi ktta grbavca. (Foto: G. Stanzani) The specimen seemed to be in distress and very weakened as confirmed by the photographs and video observation. The back, normally much smoother in an animal in good health, displayed strange indentations and "bumps". When the visual contact with the animal was lost, it was swimming south. We received no further news in the following days, either from the Coast Guard or from fishermen, so we can only assume that it left the Adriatic basin. ACKNOWLEDGMENTS Many thanks are due to Luca Amico and the Pro-tezione Civile of Numana staff and to Marco Giuliano and the Centra Sub Monte Conero, Numana for their irreplaceable support. We also thank Giampaolo Ratio, Maurizio Spoto and Paolo Zucca for promptly alerting us. PRVI ZAPIS O KITU CRBAVCU MEGAPTERA NOVAEANGLIAE (BOROVVSK1, 1781) IN THE ADRIATIC SEA Marco AFFRONTE, Leandro Augusto STANZANI & Giacorno STANZANI Fondazione Cetacea Onlus, 1-47838 Riccione (RN1, Via Milana fi3 E-mail: ambientemare@forida2ionecelacea.org POVZETEK Kit grbavec Megaptera novaeangliae (Borowski, 1781) je bil v Sredozemskem morju doslej zabeležen le petkrat, a Se nikoli v jadranskem morju. Najstarejši zapis je znan iz leta 1885, ko so v bližini Touiona v Franciji ujeli mladega grbavca. Nadalje sledijo s fotografijami dokumentirano opazovanje dveh grbavcev v vodah okoli Menorce (Baleari) iz leta 1986, zapis o mladem osebku v zalivu Gabes (Tunizija) iz leta 1992 ter zapis o nesrečno ujetem mladiču pri Cavalairu v Franciji leta 1993. Nekaj svežih podatkov o pojavljanju grbavca v grških vodah pa še čaka objavo. V pričujočem zapisu avtorji obravnavajo 90 minut dolgo opazovanje kita grbavca 4. avgusta 2002 v vodah blizu Sennigalie (43"45' N, 1315' E). Ključne besede: Megaptera novaeangliae, kit grbavec, prvi zapis, jadransko morje 53 ANNALES ■ Ser. hist. nat. ■ 13 • 2003 • 1 Marco AFFRONTS el slrRRST RECORD Of THE HUMPBACK WHALE, MfCAPTCRA NOVAEANGLIAt: (80R0WSKI, 178», FROM THE ADRIATIC SEA, 51-54 REFERENCES Buljan, M. & M, Zore-Armanda (1976): Oceanograpbi-cal properties of the Adriatic Sea. Oceanogr. Mar. BioL Annu. Rev., 14, 11-98. Frantzis, A., P. Aiexiadou, G, Paximadis, E. Politi, A. Cannier & M. Corsini-Foka (in press): Current knowledge on the cetacean fauna of the Greek Seas. J. Cetacean Res. Manage. Jann, B. & F. W. Wenzei (2001): Humpback whales in the Cape Verde Islands. Paper SC/NAH19, 1WC Scientific Committee, July 2001, London. Jann, B., J. Alien, M. Carrillo, S. Hanquet, S. K. Katona, A. R. Martin, R. R. Reeves, R. Seton, P. T, Stevick & F. W. Wenzei (in press): Migration of a humpback whale between Cape Verde Islands and Iceland, j. Cetacean Res. Manage. Leatherwood, S. & R, R. Reeves (1983): The Sierra Club Handbook of Whales and Dolphins. Sierra Club Books, San Francisco, CA, USA. Notarbartolo di Sciara, G. (2002): Cetaceans species occurring in the Mediterranean and Black Seas. In: Notarbartolo di Sciara, G. (ed.): Cetaceans species occurring in the Mediterranean and Black Seas: state of knowledge and conservation strategies. A report to the ACCOBAMS Secretariat, Monaco, February 2002, Section 3, 17 pp. Winn, H. E. & L. K, Winn (1978): The song of the humpback whale, Megaptera riovaeangliae, in the West Indies. Mar. Biol., 47, 97-114. 54 KLIMATSKE SPREMEMBE VARIAZIONI CLIMATICHE CLIMATE CHANGES ANNALES • Ser. hist, nat. • 13 • 2003 • 1 original scientific article UDK 581.5:551.542(497.4) received: 2003-04-18 SPRING PHENOLOGiCAL TRENDS IN SLOVENIA Zalika ČREP1NŠEK & Lučka KAjFEŽ-BOGATA} Biotechnical Faculty, University of Ljubljana, Si-J000 Ljubljana, jamnikarjeva 101 E-mail: zalika.crepinsek@bf.uni-tj.si ABSTRACT The long-term phytophenological and meteorological data set for the 1955-2000 period was analysed to assess the impact of increased winter and spring temperatures on the plant development in Slovenia. The 46-year series of the leaf unfolding and flowering were studied for 11 plants (herbaceous plants, shrubs and trees) at eight selected observation points. The mean linear trends in phenophases appearance were negative, ranging from -1.4 days per decade for leaf unfolding, -2.2 days per decade for late-spring flowering, and -3.1 days per decade for early-spring ■flowering. This resulted in earlier leaf unfolding of 6 days and earlier flowering of 10-14 days for the discussed period. A W-day shift to earlier spring in Slovenia corresponded well with changes in early-spring temperatures from February to April. Key words: phenology, growing season, trends, air temperature changes, Slovenia TENDENZE FENOLOGICHE PRIMAVERILI IN SLOVENÍA SINTESl : L'ártico lo riporta l'analisí di una serie pluriennale di dati fitofenologici e meteorología per il periodo 1955-2000, effettuata alio scopo di valutare l'impatto delTinnaízamento delle temperature invernalí e primaverili sullo sviluppo de i le piante in Sloveriia. La serie studiata comprende dati inerenti la schiusa delle gemme e la fioritura per 11 piante (erbacee, arbusti ed alberi) in otto postazioni d'osservazione per un periodo di 46 anni. Le tendenze lineari medie delle fenofasi sono risultate negative, variando tra -1.4 giorni per decennio per la schiusa delle gemme, -2.2 giorni per decennio per la fioritura tardo-primaverile, e -3.1 giorni per decennio per la fioritura aíi'inizio della primavera. Considerando Tintero periodo di osservazione, le autrici concludono che la schiusa delle gemme si é verificata nell'ultimo decennio con un anticipo medio di 6 giorni, mentre hanno calcolato un anticipo di 10-14 giorni per la fioritura rispetto alia prima decade di osservazione. Le variazioni osservate in Slovenia, ossia un anticipo di 10 giorni nella comparsa della primavera, corrispondono alie variazioni della temperatura dell'aria aíi'inizio del periodo primaverile, da febbraio ad aprile. Parole chiave: fenología, staglone di crescita, tendenze, variazioni della temperatura dell'aria, Slovenia 57 ANNALES • Ser. hist. nat. ■ 13 ■ 2003 • 1 Zatika ČKEPiNŠCK & Lučka KAJ FE 2-BOGATA]: SPRING PHENOLOGICAL TRENOS iN SLOVENIA, 57-64 INTRODUCTION Phytophenoiogy deals with the recurring growth and development phenomena of plants in their annual rhythm (Lieth, 1974). The occurrence times of characteristic vegetation stages (phenophases) are in close relation to the climate of the observation site and current weather. Inter-annual changes in spring plant phenology may be the most sensitive and observable indicators of the plant response to climate change {Beaubien & Free-land, 2000). There are significant differences between the way different plants species respond to climate change. Even small differences in phenology between species can lead to rather large changes in growth when they grow in mixed stands, and consequently also to a significant change of selection pressure (Kramer ef at., 2000). Earlier spring development is occtirring in different parts of Europe. The earliest flowering species in the growing season show more variability in bloom time over the years than later-flowering species (Fitter ef ai, 1995). Abas (1999) reported that springtime has advanced 8 days on average over the last 80-year period; the last 40-year period has warmed even faster. Pheno-logical data of the International Phenological gardens for the period 1969-1998 showed that the average beginning of growing season across Europe advanced by 8 days (Chmielewski & Rotzer, 2002). The investigation showed (Chmielewski & Rotzer, 2001) that a warming in the early spring (February-April) by 1 °C causes an advance in the beginning of growing season of 7 days. Study by Defila & Clot (2001) showed a clear trend towards earlier appearance dates in spring in Switzerland. For Hungary, Walkovszky (1998) investigated the changes in phenology of the locust tree: a rise in temperature by 1 °C led to a week earlier flowering. Trends in timing of phenological events have been described for England by Fitter et al. (1995) and Sparks et ai (2000). Earlier spring plant development has been reported also for North America (Beaubien & Freeland, 2000): a movement towards by 8 days in the timing of spring development was noticed in the Edmonton area (Alberta/Canada) over the last six decades. The observed trends in the onset of spring corresponded well with changes in air temperatures and circulation (North Atlantic Oscillation) in Europe (Chmielewski & Rotzer, 2001; CrepinSek ef at., 2002) respectively with Southern Oscillation over western Canada (Beaubien & Freeland, 2000). Besides being influenced by temperature and the length of day, phenological dates are mainly induced by weather during the actual vegetation period, the past vegetation period and the dormancy period (Defila & Clot, 2001). Man-induced changes are thought to be among the causes of global warming, and higher temperatures in late winter and early spring induce growing season to become earlier (Bergant et al., 2002). This study analyses long-term phenological time series to assess the impact of air temperature changes on selected plants in Slovenia, MATERIAL AND METHODS For the long-term phenological analyses only the best quality phenological data, that over at least 30 years, were selected. The study is based on eleven common plants at eight different observation points (Tab. 1), These phenological. data-series were extracted from the historical phenological data set of the Environmental Agency of Slovenia. Spring phenophases (leaf unfolding, flowering) were selected for study as the effect of climate change is more pronounced in earfy spring in Slovenia and owing to the availability of quality data set. First, logical and critical control of the data was performed including plotting of ail phenological data. No data were added or corrected because filling in the gaps could change the trends of complete records. For this study, the phenological dates of eleven species were combined in an annual leaf unfolding index, early-spring flowering index and late-spring flowering index to determine the changes at the beginning of the growing season in Slovenia for the 1955-2000 period (Tab. 1). Combining species phenophases to derive an index value has the advantage of summarizing plant responses to weather conditions over extended period or region (Castonguay & Dube, 1985; Beaubien & Freeland, 2000; Chmielewski & Rotzer, 2001). Such phenological information, combined from several stations, obtain a common but more reliable data (Schaber, 2002). For the study of phenological and mean monthly air temperature time series, the linear trend analysis was used. For statistical analysis, the STATGRAPHICS Plus 4.0 and EXCEL 2002 standard modules were applied. Correlations were calculated between phenological data and mean monthly air temperatures for 46 years (1955-2000). 58 ANNALES • Ser. hist. nat. • 13 ■ 2003 -1 --~ ZnJfci ČRERNŠEK & Lučka KAJFEŽ-BOGATAJ: SPRING PHENOi.OGICAL TRENDS IN SLOVENIA,-.57-M-: Tab- 1: Phenological data: phenophases, indicator plants, phenologies! indexes and locations. Tah. I: Fenoioški podatki: fenofaze, indikatorske rastline, fenoioški indeksi, lokacije. PHENOPHASES - First leaf unfolding date - Flowering date INDICATOR PLANTS beech -black locust - common elder - common lilac - common silver birch - dandelion - goat willow - hazel ~ horse-chestnut - large-leaved lime ■- snowdrop Fagus sylvatica L. Robinia pseudacacia I... Sambucus nigra L. Syringa vulgaris L. Betula pendula Roth. Taraxacum officinale Weber/Wiggers Salix caprea L. Cory/us avellana L. Aesculus hippocastanum L. Tilia platyphyllos Scop. Galanthus nivalis L. PHENOLOGICAL INDEXES Phenological data set was used to calculate four phenological indexes: leaf unfolding index - LI Leaf unfolding index is determined as the annual mean of the leaf unfolding dates for beech, common silver birch, large-leaved lime and horse-chestnut. Early-sprtng flowering index - fd i-'arly-pring-flowering index is determined as the annual mean of the flowering dates for common silver birch, dandelion, goat willow, haze! and snowdrop. Late-spring flowering index - F2I Late-spring flowering index is determined as the annual mean of the flowering dates for black locust, common elder, common lilac and large-leaved lime. Growing season index - GSI Growing season index is the mean value of the three phenological indexes (LI, Fsl, f^U for eleven species at eight locations: GSI - {LI + F,l + F2!)/3 LOCATIONS - Celje 46n1 S'N, 15°15'E, 242 m a.s.l - Ilirska Bistrica 45°34'N, 14°15'E, 414 m a.s.l. Lesce 46°22'N, 14n11'E, 515 m a.s.l. - Ljubljana 46°04'N, 14°31'E, 299 m a.s.l. -Maribor 46°32'N, 15°39'E, 275 m a.s.l. - Murska Sobota 46°39'N, 15°12'E, 190 m a.s.i. - Novo mesto 45<348'N, 15°11 % 220 m a.s.l. - Rateče 46°30'N, 1.3043'E, 864 m a.s.l. RESULTS Growing season index and its variability The beginning of growing season is an important feature in agriculture and forestry. Its variability is mainly driven by environmental factors, particularly by temperature. As a long-term average (1955-2000), the beginning of growing season (defined as growing season index - GSI) in Slovenia starts on 24 April. Standard deviation of growing season index is 6.7 days and variation interval 30 days. Between 1988 and 2000, 11 out of 59 ANNALES • Ser. hist, nat. • 13 • 2003 • 1 ZaSitca CREPSNŠEK & lučka KAJFEŽ-BOGATAJ: SPRING PHENOlOGICAl TRErND5 IN SLOVENiA, S7-64 Trends The trends of all phenological phases (each phenological phase is average for eight locations) are given in Table 2. All but one of the trends of the spring records were significantly negative (38% at the 0.01 level, 31% at the 0.05 level, 23% at the 0.10 level; 8% were not significant). Negative trends indicate an earlier onset of leaf unfolding and flowering during the past decades. The mean linear trends (days/decade) ranged from -1.4 for leaf unfolding, -2.2 for late-spring flowering, and -3.1 for early-spring flowering. This means a movement forward by 6 days in the timing of leafing and of 10-14 days in the timing of flowering. The growing season index showed a significant negative trend of-2.2 days per decade, corresponding to 10 days earlier beginning of growing season over the last five decades. There are differences among the spring trends of different phenophases observed, the higher trends being found for early-spring flowering of Cory I ¡us, Salix and Calanthus, indicating that changes of events occurring in the early spring are more distinct and related to considerable change In late-winter and early-spring temperatures (Fig. 3). Changes are more distinct for phenophases of flowering, indicating that these phenophases are more sensitive to air temperatures. Tab, 2: Long-term trends of spring phenological phases in Slovenia for the 1955-2000 period. Significant trends are marked as follows: "'p<0.01,' p<0.05,'p<0.10. Tab. 2: Dolgoletni trendi pomladanskih fenofaz v Sloveniji za obdobje 1955-2000- Značilni trendi so označeni: '"p<0.01, " p<0.05, 'p<0.10. Phenological phase Change (days per decade) Regression R3 I Flowering of black locust -2.6 -0.27 0.21" j Flowering of common elder -2.6 -0.25 0.21'" Flowering of common lilac -2.2 -0.21 0.16™ j Flowering of common silver birch -1.3 -0.14 0.06' | Flowering of dandelion -1.7 -0.18 0.07 I Flowering of goat willow -4.6 -0.45 0.24"" j Flowering of hazel -4.3 -0.44 0.13" j Flowering of large-leaved lime -1.3 -0.14 0.08" Flowering of snowdrop -3.7 -0.37 0.17"" I Leaf unfolding of beech -1.1 -0.11 0.10" Leaf unfolding of common silver birch -2.0 -0.19 0.13" Leaf unfolding of horse-chestnut -1.7 -0.18 0.14" Leaf unfolding of large-leaved lime -0.6 -0.07 0.03 13 years showed an earlier onset of spring comparing long-term average (Fig. 1), Five earliest springs were noticed in 1994, 1990, 1989, 2000 and 1998. The beginning of growing season was extremely early in 1994 <10 April), and extremely late in 1956 (8 May). Year Fig. 1: Long-term trend in growing season index. The Julian days are shown as deviations from the mean growing season index for all data. Si. 1: Dolgoletni trend indeksa rastne sezone. Julijanski dnevi so prikazani kot odkloni od povprečnega indeksa rastne sezone za vse podatke. 60 ANNALES • Ser. hist nat. • 13 • 2003 • 1 Zatika ČREP1NŠEK & Urclta KAJFE2-60GATA|: SPRING Pí-tEN O LOGICAL TRENDS IN SLOVENIA, .57-64 Year Fig. 2: Leaf unfolding index and air temperatures with deviations from the long-term means (1955-2000). Ver-tical bars represent the annual leaf unfolding indexes (the mean of first leaf unfolding dates for; Fagus sylva-tica, Betu I a pendula, Aesculus hippocastanum and Tilia piatyphyllos) expressed as deviations in days from the mean value. The line represents the annual deviations of temperature CC) from the spring mean iemperafure (February-April). $1. 2: Indeks oil stanja ¡n temperature zraka z odkloni od dolgoletnega povprečja (1955-2000). Navpični stolpci ponazarjajo letne indekse olistanja (povprečje datumov olistanja za Fagus sylvatica. Betula pendula, Aesculus hippocastanum in Tilia piatyphyllos), izražene kot odklon (število dni) od povprečja. Krivulja ponazarja letni odklon temperature zraka CO od povprečja temperature pomladnih mesecev (februar-april). Relations to air temperatures The annual timing of spring phenophases is largely a response to temperature and reflects thermal conditions of the current year and location. From February to April, .significant negative correlation coefficients between GSI and temperature were found, meaning that higher temperatures in early spring promote earlier flowering and leaf unfolding (Fig. 4). Annual monthly temperatures for eight locations for February, March and April were averaged for each year. These temperatures and GSI correlated at high significant correlation coefficient (R = -0.90). A comparison with the simpler relationship with the one-month temperatures confirmed that relationships were tighter when the temperatures of many months were dealt with together. The later beginning of growing season was associated well with lower than average temperatures (Figs. 1 &. 2). According to the regression equation, a warming of 1 °C promotes beginning of growing season by 4.1 days in Slovenia (Fig. 4). A trend analysis of air temperature was carried out in order to investigate the cause of spring phenological trends. Mean temperatures for the months of February, March and April were averaged for each year for eight selected locations. We found positive trend in air temperature (+ 1.6 °C) for months from February to April in the last 46 years, which explicated the observed trend at the beginning of growing season (Fig. 5). Ft'g. 3: Early-spring flowering index and air temperatures with deviations from the long-term means (1955-2000). Vertical bars represent the annual early-spring indexes (the mean of flowering dates for: Betula péndula, Taraxacum officinale, Salix caprea, Corylus avellana and Galanthus nivalis) expressed as deviations in days from the mean value. The fine represents the annual deviations of temperature CQ from the spring mean temperature (February-April). SI. 3: Indeks cvetenja v zgodnji pomladi in temperature zraka z odkloni od dolgoletnega povprečja (1955-2000). Navpični stolpci ponazarjajo letne indekse cvetenja (povprečje datumov cvetenja za: Betula pendula, Taraxacum officinale, Salix caprea, Corylus avellana in Galanthus nivalis), izražene kot odklon (število dni) od povprečja. Krivulja ponazarja letni odklon temperature zraka (°C) od povprečja temperature pomladnih mesecev (februar-april). DISCUSSION Our investigation has shown that there has been a trend to earlier leaf unfolding and flowering over the last 46 years in Slovenia. The obtained results concerning the regional trend in the beginning of growing season in Slovenia agreed with those for Europe-wide trends of Chmielewski & Rotzer (2002) and Menzel .(2000). Spring phenological trends correspond well with changes in air temperature of early spring (February-April). The results of our analysis confirm the findings of others authors concerning the influence of air temperature on the timing of spring events (Chmielewski & Rotzer, 2001). The result that an increase in mean spring temperature of 1 nC is associated with an advanced beginning of growing season by 4 days coincide with the findings of Fitter et a/. (1995) and Sparks et al. (2000). 61 ANNALES - Ser. hist. nat. • 13 ■ 2003 - 1 "^iîrCRH>!?J5ÊK"& lučka KAIRŽ-BOGATAj: SPRING PMtNOLOGICAE TRENDS IN SLOVENiÂTs'-M Fig. 4: Relationship between mean spring temperature Tfeb-Apr (February to April) and growing season index (GSt)-~ A warming of 1 "C in TM, Apr means approximately 4 days earlier beginning of growing season in Slovenia. SI. 4: Povezava med temperaturo pomladnih mesecev fpcb.Apr (februar-april) in indeksom rastne sezone (GSI). Otoplitev za 1 "C glede na Tf,.^Apr pomeni približno 4 dni zgodnejši začetek rastne sezone v Sloveniji. There is no doubt that the global wanning led to an earlier beginning of growing season. What are implications of this trend to earlier development for plant species? Plants have different sensitivities to climatic oscillations; this could lead to changes in the population dynamics. Differences in phenological response may affect competition between plant species (Kramer et al., 2000) and promote those with better adaptive response. Changes in species distribution and abundance are the expected results of climate change, which may have positive or negative effects. New crop varieties can become more productive for certain regions and on the other hand new pests, diseases or weediness risk can turn up. We would expect that flowering will remain in approximate synchrony with the pollinating species, but implications of trends in phenological responses need to be examined for all levels of system plant-environment system (Beaubien, 1996). An increasing frequency of warmer winters and springs may result in intensified damage because of late spring frosts in agronomy or forestry resulted in the year's seed production lost or decreasing forest community composition following early promoted growth. 195S 1960 1965 WO 1975 1980 1 1990 1995 2000 Year Fig. 5: Long-term trend in mean air temperature from February to April (TFeh_Apr) in Slovenia for the 1955-2000 period. SI. 5: Dolgoletni trend povprečne temperature zraka od februarja do aprila (Tfe^Ap7) v Sloveniji za obdobje 1955-2000. If the predicted winter and spring warming over the next decades is carried into effect, then we must expect a continued trend to earlier development, but a linear extrapolation of the statistical trends, found in our or In other investigations, is of course not adequate. The lower limit for a spring phenophases date is probably best determined by examining species phenology at the southern limit of their distribution (Sparks et ai, 2000). The early spring phenophases provides the best timing predictor for subsequent plant events and thus phenological data and trends over time could assist us in adapting to climate change and variability. CONCLUSIONS The most important results of this study can be summed up as follows: 1. Spring phenological data for the 1955-2000 period were combined in an annual leaf unfolding index, early spring flowering index and late spring flowering index to determine the changes at the beginning of growing season in Slovenia. 2. in the last five decades, the average beginning of growing season in Slovenia has advanced by 10 days, whereby the extreme early dates were observed in the last decade. 3. There were significant differences among the trends of different phenophases in spring: the mean linear trends ranged from -1.4 day per decade for leaf unfolding; -2.2 days per decade for late spring flowering, and -3.1 days per decade for early spring flowering. 4. The leaf unfolding was 6 days earlier and flowering 10-14 days earlier over the 46 years studied. 62 ANNALES • Ser. hist, nat. • 13 • 2003 • 1 Zaiiks ČREPiNSEK & Lutka KAjEEŽ-BOGATAj: SPRfNC, PHENOLOCICAL TRENDS IN SLOVENiA, 57-64 5. The observed trends at the beginning of growing season correspond well with the changes in air temperature in the eariy spring from February to April. 6. A warming in the eariy spring by 1 °C leads to an advanced spring by approximately 4 days in Slovenia. ACKNOWLEDGEMENTS Phenologies! and meteorological- data sets were kindly supplied by the Environmental Agency of the Slovene Ministry of the Environment, Spatial Planning and Energy. TRENDI POMLADANSKIH EENOFA2 V SLOVENIJI Zalika ČREPINŠEK & Lučka KAjFEŽ-BOGA TAJ Biotehniška fakulteta, Univerza v Ljubljani, Si-1000 Ljubljana, famnikarjeva 101 E-rrtai!: zaiika.crepin5ek@bf.1jni-lj.si POVZETEK Avtorici pričujočega prispevka sta na osnovi dolgoletnih fenoloških in meteoroloških podatkov za obdobje 1955-2000 analizirali vpliv naraščajočih temperatur zimskih in pomladnih mesecev na fenološkl razvoj rastlin v Sloveniji. Na osmih izbranih lokacijah sta analizirali 46-letni niz podatkov za fenofazo ollstanja pri bukvi, navadni brezi, navadni lipi in divjem kostanju ter za fenofazo cvetenja pri navadni brezi, regratu, ivi, leski, zvončku, robiniji, črnem bezgu, španskem bezgu in navadni lipi. Da bi ugotovili spremembe ob začetku rastne sezone, sta fenološke podatke tdružili v letnem indeksu ollstanja, indeksu cvetenja v zgodnji pomladi In indeksu cvetenja v pozni pomladi. Trendi spomladanskih fenofaz različnih rastlin so se med sabo statistično značilno razlikovali. Srednji linearni trendi (dnevi na dekado) so se gibali med -1,4 za fenofazo olistanja, -2,2 za fenofazo cvetenja v pozni pomladi in -3,1 za fenofazo cvetenja v zgodnji pomladi. V preučevanem obdobju je olistanje nastopilo v zadnji clekadi v povprečju 6 dni zgodneje, cvetenje pa 10-14 dni zgodneje glede na začetno dekado. Ugotovljene spremembe (10-dnevni zgodnejši nastop pomladi} v povprečnem začetku rastne sezone v Sloveniji so se ujemale s spremembami temperature zraka zgodaj spomladi (med februarjem in aprilom). Raziskave so pokazale, da je otoplitev za 1 °C zgodaj spomladi pospešila. začetek rastne sezone za 4 dni. Ključne besede: fenologlja, rastna sezona, trendi, spremembe temperature zraka, Slovenija REFERENCES Ahas, R. (1999): Long-term phyto-, omitho- and ich-thyophenologica! research for the 21s! century. Int. j. Biometeorol., 42(3), 1 19-123. Beaubien, E.G. (1996): Relationships between plant phenology in continental western Canada and Pacific Ocean temperatures. In: Hočevar, A., Z. Črepinšek & L. Kajfež-Bogataj (eds.): Proceedings of the 14,h International Congress of Biometeoroiogy, Ljubljana, 1-8 Sept 1996. Mednarodno biometeorološko društvo in Slovensko meteorološko društvo, Ljubljana, p. 150-160. Beaubien, £. G. & H. J. Freeland (2000): Spring phenology trends in Alberta, Canada: links to ocean temperature. Int. j. Biometeorol., 44(2), 53-59. Bergant, K., l. Kajfež-Bogataj & z. Črepinšek (2002): Statistical downscaling of GCM simulated average monthly air temperature to the beginning of flowering of dandelion (Taraxacum officinale) in Slovenia. Int. j. Biometeorol., 46(1), 22-32. Castonguay, Y. & P. A. Dube (1985): Climatic analysis of a phenoiogical zonation: A multivariate approach. Agric. Forest Meteorol., 35, 31-45. Chmielewski, F. M. & T. Rotzer (2001): Response of tree phenology to climate change across Europe. Agric. Forest Meteorol., 108(2), 101-112. Chmielewski, f. M. & T. Rotzer (2002): Annual and spatial'variability of the beginning of growing season in Europe in relation to air temperature changes. Clim. Res., 19, 257-264. 63 ANNALES • Ser. hist. nat. - 13 • 2003 • 1 ZaSïka ČRERINŠEK i. Lučka KAjPEŽ-BOCATAJ: spring PENOLOGICAL TRENDS IN SLOVENIA. S7-M Črepinšek, Z., L. Kajfež-Bogata j & K. Bergant (2002): Correlation between spring phenophases and North Atlantic oscillation index in Slovenia. Research reports. Biotechnicai Faculty, University of Ljubljana, Ljubljana, 79(1), p. 89-98. Defila, C. & B. Clot (2001): Phytophenological trends in Switzerland, int. J. Biometeorol., 45(4), 203-207. Fitter, A. H., R.S.R. Fitter, I.T.B. Harris & M. H. Williamson (1995): Relationships between first flowering date and temperature in the flora of a locality in centra! England. Funct. Ecol., 9, 55-60. Kramer, K., I. Leinonen & L. Loustau D. (2000): The importance of phenology for the evahtation of impact of climate change on growth of boreal, temperate and Mediterranean forest ecosystems: an overview. Int. }. Biometeorol., 44(2), 67-75. Lieth, H. (1974): Purposes of a Phenology Book. In: Li-eth, H. (ed.S: Phenology and Seasonality Modelling. Ecological Studies 8. Springer-Verlag, New York, 444 pp. Menzet, A. (2000): Trends in phenological phases in Europe between 1951 and 1996. Int. j. Biometeorol., 44, 76-81. Schaber, j. (2002): Phenology in Germany in the 20lh century: Methods, Analyses and Models. PIK Report No. /8. Potsdam Institute for Climate Impact Research, Potsdam, 146, 39-91. Sparks, T. H., E. P. Jeffree & C. E. Jeffree (2000): An examination of the relationship between flowering times and temperature at the national scale using long-term phenological records from the UK. int. j. Biometeorol, 44(2), 82-87. Walkovszky, A. (1998): Changes in phenology of the locust tree (Robinia pseudoacacia L.) in Hungary. Int. j. Biometeorol., 41(4), 155-160. ANNALES • Ser. hist, nat. • 13 • 2003 • 1 pregledni članek UD K 551 -582:55T.577(497^4-T-4)'ír37l B"; prejeto: 2003-04-04 SUHA IN MOKRA LETA V SUBMEDiTERANSKI SLOVENIJI OD 14. DO SREDE 19. STOLETJA Darko OCRIN Oddelek za geografijo, filozofska fakulteta, Univerza v Ljubljani, SI-1000 Ljubljana, Aškerčeva 2 E-mail: Darko. Ogrtn@ff.uni-lj,si IZVLEČEK V prispevku je prikazan poskus rekonstrukcije suhih in mokrih let v času med 14. in sredo 19. stoletja v primorskem delu Slovenije. Podatke srno večinoma črpali iz sekundarnih in terciarnih zgodovinskih virov, predvsem kronik. Podnebje slovenskega Primorja je submediteransko, z razmeroma pogostimi sušami v poletnih mesecih, ki so na Krasu tudi posledica njegovih petrografskih značilnosti. Izdelana kronologija sušnih in nadpovprečno mokrih let ne omogoča popolne klimatske rekonstrukcije, ker je podatkov premalo. Kljub temu pa lahko izločimo tri obdobja s pogostejšimi sušami: 1540 do 1662, prva polovica 18. stoletja in prva polovica 19. stoletja. Ključne besede: suša, variiranje podnebja, klimatologija, Submediteranska Slovenija, Slovenija ANNI D! SICCITA ED ANNI DI PIOGGE NELLA SLOVENIA SUBMEDITERRANEA DAL 14° ALLA META DEL 19° SECOLO SINTESI Nell'articolo viene presentato il tentativo di ricostruzione del ¡'andamento degli anni di siccita e quelli di piogge nel periodo compreso Ira il 14" e la meth del 19 secolo nei litorale sloveno. / dati provengono principalmente da fonti storiche secondarie e terziarie, soprattutto croniche. II clima del litorale sloveno e submediterraneo, con una frequenza relativamente alta di periodi di sicclfá nei mesi estivi, dovuti anche a fattori parcialmente petrografici sul Carao. La cronología ott.enuta per gli anni di siccith e per quelli di piogge non ha portato ad una ricostruzione dimatica completa, a causa di un'insufficienza di dati, Nonostante cío, l'autore evidenzia tre periodi di siccita frequente: dal 1540 al 1662, la prima meta del I ff secolo e la prima meta del 19' secolo. Parole chíave: siccitót, variazioni ciimatiche, climatología, Slovenia submediterranea, Slovenia 65 ANNALES ■ Ser. hist. nat. • 13 • 2003 ■ 1 Darko OGRIN: SUHA iN MOKRA LETA VSUBMEiXfERANSKI SLOVENIJI OD i 4. DO SREDE 19. STOLETJA, 65-74 UVOD Slovenija ima povprečno okoli 1500 mm padavin letno, kar jo uvršča med najbolj namočene predele Evrope in tudi sveta. Največ jih pade na alpsko-dinarski pregradi, v 120 do 130 padavinskih dnevih tudi več kot 3000 mm. Od tod se namočenost zmanjšuje proti morju, kjer zabeležijo kakih 1000 mm padavin v okoli 100 padavinskih dneh in proti V oziroma SV, kjer jih v Prekmurju pade od 800 do 900 mm (Ogrin, 2002; Vrhovec, 2.002). Razporeditev padavin prek celotnega leta je razmeroma enakomerna, zato običajno ni daljših in izrazitih sušnih ali namočenih obdobij. Posledica dobre namo-čenosti in zmernih temperatur je vlažnostni suficit, saj v Sloveniji ni pokrajine, kjer bi potencialna evapo-transpiracija glede na dolgoletna povprečja presegla količino padavin. Določen primanjkljaj se pojavlja samo v poletnih mesecih v Primorju in Prekmurju, kjer pa je običajno vendarle dovolj padavin za normalno rast vegetacije. Neugodna značilnost padavin v Sloveniji je njihova velika variabilnost. V povprečju znaša okoli 30%, v posameznih letih pa je pri mesečnih vsotah dolgoletno povprečje lahko preseženo za več kot 100% ali pa padavin praktično ni, in to ne glede na letni čas. Posledica tega so lahko suše in poplave. Problem aktualnih suš, še posebej v kmetijstvu, je dobro poznan in v strokovni literaturi ustrezno predstavljen (npr. Natek, 1987; Dolinar-Lešnik, 1989; Matajc, 1991, 1995, 1996, 2002; Gams, 1999). Še bolj pereč pa bi utegnil postati problem pomanjkanja vlage v rastni sezoni z vidika napovedanih podnebnih sprememb, kar nakazuje zadnje desetletje, ko temperature naraščajo in so suše pogostejše. Po nekaterih napovedih (Kajfež-Bogataj, 1998; Anonymous, 2001) naj bi se temperature v Sloveniji do srede tega stoletja povečale za okoli 2 °C, količina padavin pa zmanjšala za 10 do 20%. To bi pomenilo razširitev zaradi suše potencialno ogroženih območij in večjo pogostost in intenzivnost suš v pokrajinah, ki so jih suše ogrožale tudi doslej, med njimi tudi dela Slovenije s submediteranskim podnebjem. Pri teli napovedih pa je pogosto zanemarjeno dejstvo, da se je podnebje spreminjalo tudi v preteklosti in da smo že imeli obdobja, ko so bile tudi suše pogostejše. Poznavanje preteklega podnebja in njegovih posledic pa je lahko dobra osnova za oceno razmer in ogroženosti v prihodnje. V prispevku smo se omejili na problem osvetlitve suš v predinstrumentalnem obdobju, to je pred letom 1841, ko je začela delovati meteorološka postaja v Trstu. Tržaška postaja je namreč dober reprezentant klimatskih razmer v Submediteranski Sloveniji, še posebej obalnega dela, njeni kontinuirani podatki pa dajejo dobro osnovo za študij variacij podnebja od srede 19. stoletja do današnjih dni. Za zdaj pa imamo zelo skromno podatkovno bazo za študij razmer v času pred začetkom delovanja te postaje. PODNEBNE ZNAČILNOSTI SUBMED1TERANSKE SLOVENIJE Z imenom Submediteranska Slovenija označujemo nižji ]Z de! Slovenije, ki je reliefno odprt proti Tržaškemu zalivu oziroma jadranskemu morju in ima zato milejše klimatske poteze v primerjavi s pokrajinami v notranjosti Slovenije. Orografska pregrada južnih julijskih Alp in do 1500 m visokih dinarskih planot (Banjšice, Trnovski gozd, Nanos, Hrušica, javorniki, Vremščica in Snežnik) razmejuje pokrajine, v katerih še prevladujejo poteze mediteranskega podnebja, od preostale Slovenije, ki ima zmerno kontinentalno oziroma gorsko podnebje (Si. 1). Značilnosti mediteranskega podnebja se prepletajo z vplivi celinskega in gorskega podnebja, kar se kaže v nekoliko nižjih temperaturah ter več padavinah kot pri pravem mediteranskem podnebju in modificiranem padavinskem režimu. V geografski in klimatološki literaturi (npr. Ogrin, 1996; Gams, 1998) zato to podnebje označujemo za omiljeno mediteransko oziroma subrnediteransko, predel Slovenije, ki ima to podnebje, pa Submediteranska Slovenija. Zanj so značilne pozitivne povprečne januarske temperature, julijske temperature nad 20 "C in 2000 do 2400 ur s soncem na leto, kar je največ v Sloveniji. Zaradi zadrževalnega učinka morja so jesenske temperature višje od spomladanskih. Padavin je od 1000 mm ob obali, do 1700 mm ob vznožju reliefnih pregrad, kjer so razmeroma enakomerno razporejene prek celotnega leta. Kljub temu pa sta opazna dva viška in dva nižka padavin, ki sta posledica prepletanja mediteranskih in celinskih podnebnih značilnosti. Običajno pade največ padavin jeseni, novembra ali oktobra, sekundarni višek je junija na prehodu pomladi v poletje. Najmanj padavin je na prehodu zime v pomlad (januar, februar, marec) ter v juliju in avgustu (Ogrin, 1996). V letnem povprečju potencialna evapotranspiracija ne presega količine padavin, a se v topli polovici leta zaradi visokih temperatur pojavlja vlažnostni deficit, in to kljub temu da v povprečju pade tudi v poletnih mesecih od 80 do 100 mm padavin (Pristov, 1994). Primanjkljaj, ki je največji v obalnih predelih, kjer imajo 2 do 4 "C višje temperature in prejmejo manj padavin, traja od maja do avgusta. Vlažnostni deficit je manjši in obdobje z njim teoretično krajše v višjem in bliže reliefni pregradi ležečem širšem zaledju Tržaškega zaliva. Toda dejanski učinek suše je v kraškem zaledju kljub pogostejšim padavinam in nekoliko nižjim temperaturam zaradi tanke odeje prsti in njene slabe sposobnosti za zadrževanje vlage prav tako velik kakor v ftišni pokrajini ob morju. Zato so te pokrajine zaradi suše enako ogrožene kakor priobalni predeli. ANNALES • Ser. hist. na t. • 13 • 2003 • 1 Darko OCR IN: SUHA IN MOKÎaIÊTA V 5UBMEDITERANSKI SLOVEN!)! OD M. DO S REDE 1«. STOE.ftJA, 65-74 «USSKA Podnebni tipt/ Climate Type 1. submecfiteransko podnebje I Submediterranean Climat f_z; 2. imorfiokontinenlainc podnebje/ Temperate Continental Climate £31 3. gorsko podnebje / Mountainous Climat Si;-;:.)!' R^j J F M A M J JASOND JfMAHJJASOND J F HAIiÎJ A SON D SI. 1: Podnebni tipi v Sloveniji in klimogrami za nekatere meteorološke postaje v Submedtteranski Sloveniji. Fig. 1: Climate types in Slovenia and climad'tagrams for same meteoroiogic stations in Submediterranean Slovenia. 67 ANNALES • Ser. hist, nat. • 13 • 2003 • 1 Darko OCR IN: SUHA !N MOKRA LETA V SURiMiTDITf RAN.SKI SLOVENIJI OD 14. DO 5RLDE 19- STOLETJA. 65-74 SUŠE V SUBMED1TERANSKI SLOVENIj! V PRED1NSTRUMENTALNEM OBDOBJU Metodologija Suše in moče v Submediteranski Sloveniji v pred-instrumentalnem obdobju smo vsaj delno poskusili rekonstruirati s pomočjo kronike izrednih vremenskih dogodkov za Submediteransko Slovenijo (Ogrin, 1994, 1995), ki smo jo sestavili večinoma na podlagi sekundarnih in terciarnih zgodovinskih virov, za prvo polovico 19. stoletja pa tudi s pomočjo primarnih virov o proizvodnji soli v Piranskih solinah (PAK, enota Piran). Kronika zajema predvsem dogodke v ¡stri, Trstu ter ožjem in širšem zaledju Tržaškega zaliva, vključno s Krasom in Goriško. Izhodišče za oblikovanje naše kronologije je bila kronika vremenskih dogodkov, ki jo je za Trst, Istro in vzhodno Furlanijo sestavil Braun (1934). Njegovi glavni viri so bili anali Jennerja za Trst do ieta 1846, kronologija Gorice Della Bonne do leta 1500, Tržaški anali Scusse do leta 1695 in Kandlerja od 1695 do 1848, zgodovina Trsta Irenea della Croceja od leta 1000 do leta 1702, tržaška kronika Mainatija od 11. stoletja do začetka 19. stoletja, anali Di Manzana za Furlanijo, kronika Rovinja Biancinija od leta 1760 do 1806 in Kertov vremenski dnevnik za Trst od leta 1815 do 1858. Braunovo kroniko (Braun, 1934) smo dopolnili z viri, ki jih avtor ni upošteval, npr. s kroniko Schiavuzzija (1889) in 'Tasti Istriani", kroniko dogodkov, ki je izhajala v časopisu "Llstria" (1846-1852). Črpali smo tudi iz Dolničarjeve ljubljanske kronike 1660-1718 (Pučnik, 1980) in Valvasorjeve "Slave Vojvodine Kranjske" (Valvasor, 1984). Kronika izrednih vremenskih dogodkov za Submedi- teransko Slovenijo vsebuje predvsem podatke o hidroloških učinkih vremena (poplave, presihanje studencev in vodnjakov), o posledicah za kmetijstvo {dobre in slabe letine, zgodnje in zapoznelo cvetenje ali zorenje), o ekonomskih učinkih (pomanjkanja, spreminjanje cen, lakote) in o neposrednih vremenskih učinkih (zmrzali, suše, moče, viharji ipd.). Podatkov za obdobje do 16. stoletja je manj in so tudi manj zanesljivi. Več jih je za 17. in 18. stoletje, ko se po dveh ali več neodvisnih virih tudi pokrivajo, kar povečuje njihovo zanesljivost. Kronologija suš in moč od 14. do srede 19. stoletja Kronika izrednih vremenskih dogodkov za Submediteransko Slovenijo je bila narejena za obdobje od 7. stoletja naprej, vendar prvi zapis o suši izvira šele iz prve polovice 14. stoletja (1324). Di Manzanovo poročilo govori, da je v tem letu od marca do konca julija vladala suša, z izjemo obilnega deževja v začetku junija, in da ni padlo skoraj nič dežja od 22. junija do božiča. Zgostitev poročil o suši beležimo od srede 16. stoletja naprej. Na splošno velja, da je zapisov o sušah oziroma mokrih letih neprimerno manj kot npr. zapisov o zmrzalih, kljub temu pa več kot poročil o milih zimah in neurjih. Vesti o sušah se nanašajo predvsem na poletje in zimsko-spomladanski čas, kar kaže na iden-tičnost padavinskega režima v primerjavi s sedanjostjo. Glede na koncentracijo dogodkov lahko izločimo tri obdobja s pogostimi sušami. Prvo je bilo med 1540 in 1562, ko imamo šest poročil (1540, 1546, 1548, 1559, 1561 in 1562). Iz zapisov je razvidno, da je Šlo v dveh primerih za sušo v vegetacijski dobi, ki je povzročila veliko težav v vsakdanjem življenju (Tab. 1), enkrat pa za sušo v zimsko-spomladanskem času. V treh primerih pa letni čas ni eksplicitno naveden. Tab. 1: Zapisi o sušah v obdobju 1540-1562. Tab. 1: Records of droughts in tbe 1540-1562 period. Leto / Year Opis pojava / Description of phenomena Vir / Sotirce 1540 Tudi v tem letu je bila na Kranjskem izredno velika vročina in sončna pripeka, da se je od suše ne le zemlja ko kamen strdila, temveč se je dosti gozdov vnelo. Od novembra 1539 do aprila 1540 ni ne deževalo ne snežilo. Vafvasor (1984), Kert (v Braun, 1934) 1546 Huda sLiša, zaradi katere je v nekaterih predelih ¡stre odmrlo sadno drevje in bila uničena tetina. Suši je sledilo veliko pomanjkanje in lakota. Schiavuzzi (1889) 1548 Huda suša v Istri. Schiavuzzi (1889) 1559 Huda suša v Istri. Sušilo se je sadno drevje, uničena je bila letina. Velika suša v Furlaniji, poletje je bilo skoraj brez padavin. Bilo je leto velikega pomanjkanja. Schiavuzzi (1889), Di Manzano (v Braun, 1934) 1561 Huda suša v istri. Schiavuzzi (1889) 1562 Huda suša v istri. Schiavuzzi (1889) 68 ANNALES • Ser. hist. nat. • 13 • 2003 • 1 Darko OGR1N: SUHA iN MOKRA UTA V SUBMEDiTíRANSKI SLOVENIJ5 OD 14. DO SREDE 19. STOLETJA, 63-74 V 17. stoletju so bila napravljena štiri poročila o sušah. Leta 1616 je po Fastih Istrianih Istro zajela velika vročina s sušo, da je živina poginjaia in so ljudje zbolevali. Za leto 1644 več virov (Ireneo, Mainati, Scussa) (v Braun, 1934) govori o hudi vročini z izredno sušo, ki je uničila vse poljske pridelke v tržaški okolici. Omenjajo tudi, cla so se pojavile kobilice, ki so pojedle vse, kar ni uničila suša, celo figove liste. Mainati za leto 1660 poroča o suši pomladi, poleti in jeseni in o velikem pomanjkanju vode, Ireneo pa o suši med 22, septembrom in 24. novembrom 1691, zaradi katere je v Trstu in okolici primanjkovalo vode za pitje, v Žaveljski dolini pa za mletje, jesenski suši 1660 in 1691 sta prvi poročili o suši v letnem času, ko imamo običajno višek padavin. ■.. Pogosteje so se suše ponovno pojavljale v prvi polovici 18. stoletja. Pet navedb se nanaša na suše v ■vegetacijski dobi (1704, 1717, 1718, 1735 in 1747), tri (1734, 1737 in 1745) pa na sušo v zitnsko-spomla-'danskih mesecih (Tab. 2). Leta 1748 pa je suša razsajala tako poleti kot. pozimi in spomladi. Iz druge polovice 18. stoletja imamo tri poročila o sušah. Leta 1784 ni po Bianclniju deževalo od 30. aprila do 8. septembra. Po istem viru je bila zelo huda suša, zaradi katere v Istri praktično ni bilo pitne vode, v prvi polovici leta 1794 in tudi spomladi leta 1795. Na ■splošno je bilo leto 1795 leto vremenskih katastrof, saj je bila zima zelo ostra in so pomrznile oljke. Ostri zimi je sledila suha pomlad. Poleti pa so bili hudi nalivi, ki so uničili žitno letino. Narasle vode so preplavile Sečo- veljske soline, svoj tok je spremenila tudi Dragonja. Po številu poročil o sušah (14) bode v oči tudi prva polovica 19, stoletja, zlasti obdobje od leta 1820 do 1848, v katerem so kronisti zabeležili kar 12 let s sušnimi poletji, kar pomeni, cla je bilo vsako drugo do tretje poletje suho (Tab. 3). Pri sklepanju o nadpovprečni sušnosti poletij v prvi polovici 19, stoletja moramo v primerjavi s prejšnjimi stoletji upoštevati dejstvo, da se je v 19. stoletju zelo povečalo Število pisnih virov. V našem primeru predvsem po zaslugi Kerta (v Braun, 1934), ki je sistematično vodil vremenski dnevnik za Trst. Leta 1834 ponovno srečamo tudi poročilo o suši oktobra in novembra. Primerjava Kertovih zabeležk o sušah v 40. tih letih 19. stoletja s podatki meteorološke postaje Trst, ki je začela delovati leta 1841, je pokazala, da moramo biti pri uporabi tovrstnih podatkov previdni oziroma da je problem definicije suše zelo kompleksen. Kert omenja hude suše poleti 1841, 1842 in 1848 ter "običajno" sušo 1843. Čeprav suša ni odvisna samo od količine padavin in števila padavinskih dni, je primerjava s klimatskimi podatki pokazala, da je v primeru suš leta 1841, 1843 in 1848 dejansko padlo v sušnih mesecih le 50 do 60% stoletnega povprečja padavin v pol manj padavinskih dnevih. Ob Kertovi omembi hude suše avgusta in septembra 1842 pa je v teh dveh mesecih padlo celo za 23% več padavin od povprečja v povprečnem številu padavinskih dni. Podrobnejši pregled podatkov pa je zato pokazal, da je pred tem v juniju in juliju padla le okoli tretjina običajnih padavin. Tab. 2: Zapisi o sušah iz prve polovice 18. stoletja. Tab. 2: Records of droughts from the first half of the 18 "' century. Leto / Year Opis pojava / Description of phenomena Vir / Source 1704 Nenavadno suho leto. Bilo je veliko (vina) dolenjca, vipavca malo, a dobrega. Na Goriškem je bila poleti, še zlasti avgusta, velika suša, vendar je bilo obilo vina, toda primanjkovalo je vseh vrst žit. Dolnfcir (v Pučnik, 1980), Di Manzano (v Braun, 1934) ' 1717 Trgatev je bila na Goriškem zelo skromna, Izjemni pa sta bili vročina in suša. Di Manzano (v Braun, 1934) 1718 Suho, vroče in zdravo leto. Žita je bilo dovolj, razen ob morju, kjer je bilo pomanjkanje. Sušno vreme je uničilo kmetijske pridelke, grozdje in olive, kar je zeio prizadelo piranske meščane. Dolničar (v Pučnik, 1980), PAK Piran 1734 Velika suša v prvih treh mesecih v Trstu, do 26. in 27. marca je padlo le nekaj kapelj dežja. Di Manzano (v Braun, 1 934) 1735 Do 24. in 25. septembra ni v Trstu deževalo dva meseca. Scussa (v Braun, 1934) 1737 Do 18. februarja je v dveh mesecih padlo le malo dežja in vode v vodnjakih je zelo malo. Scussa (v Braun, 1934) 1745 Od 5. januarja do 11. februarja hud mraz in suša, da je zmanjkovalo vode v nekaterih tržaških vodnjakih. Scussa (v Braun, 1934) : 1747 Poleti vročina in suša. Scussa (v Braun, 1934) : 1748 Od 1. novembra 1747 do avgusta 1748 je zelo redko deževalo. Spomladi in poleti je bila v Trstu velika vročina. Scussa (v Braun, 1934) 69 ANNALES • Ser. hist. nat. • 1.3 • 2003 • 1 DiJi'kiS OGEIN: 5UMA IN MOKRA UTA V SUBMEDiïERANSK! SLOVEMJi OD 14. DO SREDE 15. STOLETJA, 65-74 Tab. 3: Suše v prvi polovici 19. stoletja. Tab. 3: Droughts in the first half of the 19lh century. Leto / Year Opis pojava / Description of phenomena Vir /Source | 1802 Trdovratna suša v prvi polovici pomladi in vse poletje. Ljudje so trpeli zaradi velike vročine, pridelki so bili požgani. V Trstu je primanjkovalo vode. Mainati* j 1820 Od avgusta do septembra suša. Kert* 1822 V marcu in aprilu ter od junija do avgusta je bila suša. Kert* 1828 julija in avgusta huda suša v Trstu. Kert* 1830 V juliju in avgustu velika vročina in suša. Kert* 1832 Avgusta je bila huda suša. Kert* 1833 Jantiarja in julija je bila suša. Kert* 1834 Od aprila do avgtista in v oktobru in novembru je bila v Trstu suša. Kert* i 1835 Suša od junija do avgusta. Kert* 18.39 V juliju in avgustu je bila suša. Kert* 1841 Od julija do septembra huda suša v Trstu. Kert* 1842 Avgusta in septembra huda suša. Kert* 1843 Avgusta in septembra je bila suša. Kert* 1848 AvgLista in septembra huda suša. Kert* * vsi v Braun (1934) Poročil o deževnih letih (letnih časih) je razmeroma malo, le devet (Tab. 4). Pet se jih nanaša na konec 17. in začetek 18. stoletja. Začetek 18. stoletja lahko opredelimo kot nadpovprečno namočen, saj viri omenjajo leta 1703, 1706, 1711 in 1715 kot nenavadno mokra. Poročili za leti 1691 in 1827 govorita o neobičajnih deževjih v času viškov padavin v submediteranskem podnebju, prvo v času primarnega viška v jesenskem Tab. 4: Nadpovprečno namočena leta in letni časi. Tab. 4: Extraordinary wet years and seasons. času, drugo pa v času sekundarnega viška junija. Poročilo za leto 1801/02 pa govori o zelo vlažni zimi. Neprimerno več je v kroniki poročil o deževnih ujmah s točo in močnim vetrom v posameznih dnevih in posledicah teh deževij, ¡2 katerih pa ne moremo sklepati o namočenosti posameznih daljših časovnih obdobij. Po teh dogodkih zbujata pozornost zlasti 17. stoletje (12 zapisov) in sredina 18. stoletja (5 zapisov). Leto / Year Opis pojava / Description of phenomena Vir / Source 1304 izredno leto po količini snega v Furlaniji. Deila Bona (v Braun, 1934) 1691 24.11.1691 se je začelo 8-dnevno nepretrgano deževje. Sledil mu je šibkejši dež, ki ni ponehal do 16. decembra. ireneo (v Braun, 1934) 1703 Nenavadno mokro leto. Bilo je mnogo povodnji. Izjemno leto zaradi nenehnega deževja, prestopanja bregov rek in velike škode, ki so jo vode povzročile v Goriški pokrajini. Dolničar (v Pučnik, 1980), Di Manzano (v Braun, 1934) 1706 To leto je bilo mokro in jug je neprestano gospodoval. 5.avgusta je grozna nevihta povzročila ogromno škodo na Tržaškem in odvzela ljudem pridelek. Dolničar (v Pučnik, 1980), Mainati (v Braun, 1934) 1711 To leto je bilo nenavadno mokro, kakor ga ne pomnijo niti najstarejši ljudje. Skoro vse leto je prevladoval jug in je vedno deževalo, razen nekaj časa poleti. Dolničar (v Pučnik, 1980) 1715 Na splošno mokro leto, ki je sledilo dolgi zimi. Slaba vinska letina. Dolničar (v Pučnik, 1980) 1801/02 Zelo vlažna zima, ki ji je sledila trovratna suša v prvi polovici pomladi in vse poletje. Mainati (v Braun, 1934) 1815 Veliko deževje povzroči več nevšečnosti. Pasti Istriani 1827 Junija nenehno dežuje. Kert (v Braun, 1934) 70 ANNALES • Ser. hist, nat. • 13 • 2003 • 1 Darko OCR IN: StJHA IN MOKRA LETA V SUSMCDSTERANSSS SLOVENIJI OD 14. OQ 5RCOE IS. STOLETJA, (jS-M Rekonstrukcija poletnih padavin v prvi polovici 19. stoletja s pomočjo podatkov o pridobivanju soli v Piranskih solinah Solinarstvo je dejavnost, ki je skoraj v celoti odvisna od vremena, saj vse faze pridobivanja soii potekajo na prostem. Tehnologija pridobivanja soli v Piranskih solinah se je skozi stoletja razmeroma malo spreminjala, zalo so podatki o proizvodnji soli lahko dobra osnova za klimatske rekonstrukcije. Osnovni proces pri pridobivanju soli je postopno izparevanje morske vode, dokler koncentracija soii toliko ne naraste, da nastopi kristalizacija. Izparevanje je odvisno od sončnega obsevanja, padavin, števila oblačnih in jasnih dni, vlažnosti zraka in vetrovnosti. Bolj ko je vreme jasno, ■ sončno, suho in vetrovno, večji je pridelek. Vremenske in podnebne razmere v severnem Jadranu omogočajo začetek solne sezone v aprilu ali v začetku maja, traja pa do septembra oziroma prvega večjega deževja ob koncu poletja. Jedro solne sezone sestavljajo trije poletni meseci. Ob razmeroma stabilnih družbenih razmerah proizvodnje (površina kristaliza-cijskih bazenov, delovna sila, vzdrževanost solin, tudi omejitve proizvodnje kot posledica državnega monopola, gospodarske in politične razmere) je varitranje proizvodnje v visoki korelaciji s potekom vremena v času solne sezone, predvsem padavinskimi razmerami. V dveh testnih obdobjih (1926-1936 in 1961-90), ko je imel na voljo tako podatke o vsakoletni proizvodnji soli kot o količini padavin in številu padavinskih dni, je Ogrin (1995) izračunal, da lahko s padavinskimi parametri pojasnimo od 52 do 85% variance proizvodnje soli. Večji delež pojasnjene variance je bil ugotovljen za ■obdobje med obema svetovnima vojnama, ko so bile družbene razmere za proizvodnjo stabilnejše. Solinarstvo v Piranu ima po nekaterih virih (npr, Pahor & Poberaj, 1964) tisočletno tradicijo. Podatki za ■ zgodnejša stoletja so bolj fragmentarni in težko dosegljivi, več jih je in so laže dosegljivi za zadnja stoietja. Za rekonstrukcijo klimatskih razmer so predvsem zanimiva obdobja, ko proizvodnja soli zaradi državnih monopolov ni bila omejena, ampak je trajala, dokler so to dopuščale vremenske razmere. Eno takih je bilo obdobje med 1749 in 1823. Kontinuirane podatke nam je uspelo dobiti za čas med 1791 in 1823 (Ni-colich, 1882; PAK enota Piran). Po letu 1824 je bilo pridobivanje soli omejeno. Rekonstrukcija za to obdobje (SI. 2), pri kateri smo upoštevali že prej ugotovljene statistične zveze med proizvodnjo soli in padavinskimi razmerami in kjer smo vsakoletno proizvodnjo preračunali na enoto kristali-zacijske površine, je pokazala dve obdobji z bolj suhimi in tri obdobja z bolj deževnimi poletji. Suha poletja z ugodnimi razmerami za izparevanje morske vode so bila med 1808 in 1811, še bolj sušna pa med 1818 in 1822. V kronikah ni kakih posebnih zabeležb o suhih suha poletja dyy surrirrsbrs" r~h' m \ ! JUT rrwykra pnlsJfa Wi>-t StrrtlFTierS ji-... ieta ydars SI. 2: Rekonstrukcija poletnih padavin s pomočjo podatkov o proizvodnji soli v Piranskih solinah v obdobju 1791-1824, Fig. 2: Reconstruction of summer precipitation with the aid of data on salt production at Piran saltpans in the 1791-1824 period. poletjih med 1808 in 1811. Le Nicolich (1882) omenja, da je bilo v času ilirskih provinc (1809 do 1813) vreme za pridobivanje soli na splošno ugodno. Za rekonstruirano sušno obdobje 1818-1822 kronike navajajo kot sušno leto 1820. Poročila o pridobivanju soli, kjer so večinoma na kratko opisane tudi vremenske razmere, omenjajo kot suho tudi leto 1822, medtem ko so bile v drugih letih zelo ugodne razmere za pridobivanje soli samo v delu solne sezone. Po naši rekonstrukciji so bila deževna poletja med 1794 in 1796, med 1798 in 1800 ter med 1812 in 1817. Za prvo obdobje kronike omenjajo močna deževja s povodnji po 20. juniju 1795. Tega leta so v Piranskih solinah proizvedli slabo tretjino povprečne proizvodnje. Še pogostejša so bila deževja poleti 1799. Nicolich (1882) navaja, da je bila žetev soli dejansko povsem onemogočena, saj so proizvedli le 0,4% običajne količine. Deževna poletja med 1812 in 1817 potrjujejo tudi zapisi v arhivskem gradivu. Velika deževja omenjajo v letu 1815, prav tako leta 1816, ko so "vode s hribovja" in visoko morje preplavili soline. Poplavljene so bile tudi avgusta 1817, ko so morali že avgusta prekiniti s solno sezono. ZAKLJUČEK Razmeroma pogoste suše v zadnjem desetletju v Suhmediteranski Sloveniji so sprožile razmišljanja o nenavadni pogostosti tega pojava. Vzroke za to smo velikokrat iskali tudi v antropogenem efektu tople grede in klimatskih spremembah, povezanih z njim. Kratka in za zdaj nepopolna kronologija pojavljanja suš v preteklih stoletjih pa je pokazala, da so se zgostitve suš v posameznih obdobjih pojavljale tudi v preteklosti, ko človekovi vplivi na klimo še niso bili tako izraziti. Taka obdobja so bila 1540-1562, prva polovica 18. stoletja in 71 ANNALES • Ser. hist, nat. • 13 • 2003 • 1 DarSiO OGRiN: SUHA IN MOKRA i ElA V SUSMEDiTERANSK! SS.OVEN5[! OD !•!. DO 5REDF 19 STOIETJA, 65-74 Si. 3: Ob suš/ poleti 1999 so hrasti puhavci (Quercus pubescens) na Podgorskem krasu prešli v obdobje mirovanja (Ustje je porjavelo), po dežju sredi septembra pa so odgnali novi Usti. (Foto: D. Ogrin) Fig. 3: During the 1999 drought, Downy Oaks (Quercus pubesc.ens) in the Karst area of Podgorje passed into a dormancy period (leaves turned brown), but after the mid- September rainfall new leaves appeared, (Photo: D. Ogrin) čas med 1820 in 1848. Nekatera poročila (množične invazije kobilic žerk) pa napeljujejo na misel, da je bilo v posameznih krajših obdobjih morda celo bolj sušno in vroče kot v zadnjih letih, razmere naj bi bile podobne subtropskim, od koder kobilice izvirajo. Kronisti so "napade" kobilic zabeležili leta 1442 in 1475, iz katerih sicer nimamo sočasnih poročil o suhih in vročih razmerah, pač pa se časovno ujemajo invazije kobilic s sušami in vročinami leta 1644, 1720 in 1741. V zadnjem desetletju so v južni Evropi invazije kobilic doživeli na Siciliji in v Španiji. Glede na pojavljanje suš po letnih časih lahko sklepamo, da je bil padavinski režim v preteklih stoletjih identičen današnjemu. Velika večina poročil o sušah se namreč nanaša bodisi na vegetacijsko dobo (poletje) (SI. 3) bodisi na zimske oziroma zgodnje spomladanske mesece, to je na čas, ko ¡mamo tudi v sedanjem sub-mediteranskem podnebju nižka padavin. Na nespre- menjenost padavinskega režima kažejo tudi zabeležbe o moča h, ki se večinoma nanašajo bodisi na jesenske mesece bodisi na zgodnje poletje, ko v povprečju nastopata sedanja viška padavin. Mokra leta (sezone) so glede na zabeležbe v arhivskih.virih redkejši pojav. Obdobje z njihovo večjo koncentracijo je bilo le v začetku 18. stoletja med 1703 in 1715, Moča m so v nadaljevanju prve polovice 18. stoletja sledile suše, kar je izjemno poslabšalo življenjske razmere v tem času. Predstavljena kronologija suš in moč v Submedi-teranski Sloveniji ne omogoča popolne klimatske rekonstrukcije, ker je podatkov premalo. Po zbranem gradivu lahko le sklepamo na določene tendence klime, a je vsekakor osnova za nadaljnje raziskave v tej smeri. Za rekonstrukcijo padavinskih razmer poleti se zdi še posebej perspektivno arhivsko gradivo o proizvodnji soli v Istrskih solinah. 72 ANNALES • Ser. hist, nat. • 13 • 2003 • 1 Darko O GRIN: SUHA IN MOKRA LETA V SUBMEDITERANSKi SI.QVENjji OD 14. DO SREDE 13. STOLETJA, 65-74 DRY AND WET YEARS IN SUBMEDITERRANEAN SLOVENIA FROM THE 14th TO THE MID-19th CENTURIES Darko OGRIN Department of Geography, Faculty of Arts, University of Ljubljana, Sl-1000 Ljubljana, Aškerčeva 2 E-mail: Darko.Ogrin@ff.uni-lj.si SUMMARY The quite frequent occurrence of droughts in Submediterranean Slovenia in the last, decade raised a number of questions about the extraordinary frequency of this phenomenon during this particular time. The causes for such state of affairs have been often searched for in the anthropogenic greenhouse effect and its related climatic changes. However, a short and still incomplete chronology of droughts in the past centuries has shown that: the concentration of droughts in individual periods had occurred a/ready in the past, when human impacts on climate had not been so explicit as yet Such periods were from 1540 to 1562, in the first half of the 18" cent., and from 1820 to 1848. Certain reports (on locusts, for example) have brought us to a conclusion that individual shorter periods in the past were even dryer and hotter than those in the last few years; the climate conditions then seem to have been similar to the subtropical climate, where locusts came from. The chroniclers recorded the invasions by locusts in 1442 and 1475, but did not record dry and hot weather concurrently; however, the locust invasions in 1644, 1720 and 1741 overlap with the reported droughts and hot weather. From the reconstructed occurrence of droughts in individual seasons we can conclude that the precipitation regime of the past centuries has been identical to the present regime. Namely, the great majority of reports on drought refer to the vegetation period (summer), or to the winter or early spring months. These are the very periods when precipitation minimum occurs in the present submediterranean climate as well. The unchanged characteristics of the precipitation regime are also evident from the records on wet seasons, which mainly refer to the autumn months or early summer. These are also the periods when, on average, precipitation maximums occur in the present submediterranean climate. Wet years (seasons.) were less frequent according to the records from archival sources. The penod of their greafer concentration was at the beginning of the 18"' cent, from 1703 to 171.5. Wet periods were then followed by droughts in the first half of the 18"' cent., which greatly impaired the living conditions of that time. Because of the lack of data, the presented chronology of droughts and wet seasons in Submediterranean Slovenia does not render possible a complete climatic reconstruction. The collected material only enables some conclusions to be made about certain trends in the climate; nevertheless, it certainly represents a firm basis for further investigations in this particular field. Especially promising for the reconstruction of precipitation conditions in the summer seems to be the archival documents on salt production in Istrian saltpans. Key words: drought, climate variation, climatology, Submediterranean Slovenia, Slovenia LITERATURA Anonymous (2001): Prvo poročilo Konferenci pogodbenic Okvirne konvencije ZN o spremembi podnebja. MOP R Slovenije, Ljubljana, 91 str. Braun, G. (1934): Notizie meteorologiche e climato-logiche della Regione Giulia (Trieste, Istria e Friuli Orientale). Consilio Nazionale della Ricerche, Roma, 60 pp. Dolinar-Lešnik, M. (1989): Vpliv suše na kmetijsko proizvodnjo. Ujma, 3, 7-9. East i Istriani (ur. Kandier): L'lstria. Trst, 1846-1852. Gams, I. (1998): Vreme, sončno obsevanje in temperature. V: Gams, I. & I. Vrišer (ur.): Geografija Slovenije. Slovenska matica, Ljubljana, str. 91-116. Gams, 1, (1999): Spremenljivi sezonski padavinski režim in njegov vpliv na suše in povodnji. Ujma 13, 195-198. Kajfež-Bogataj, L. (1998): Bo suša v Sloveniji bolj pogosta? Gea, 8-9, str. 69. Klimatografija Slovenije (1995): Padavine 1961-90. Hidrometeorološki zavod R Slovenije, Ljubljana, 366 str. Klimatografija Slovenije (1995): Temperatura zraka 1961-90. Hidrometeorološki zavod R Slovenije, Ljubljana, 356 str. Mataje, I. (1991): Suša v kmetijstvu in namakanje. Ujma, 5, 153-156. Mataje, I. (1995): Kmetijska suša in namakanje v Prekmurju leta 1994. Ujma, 9, 55-85. Mataje, I. (1996): Vpliv sušnih šn deževnih obdobij na pridelavo kmetijskih rastlin. Ujma, 11,138-142. 73 ANNALES • Ser. hist. nat. • 1.3 • 2003 • 1 Darko OCSUN: SUHA IN MOKRA LETA V SUBMKD1TF.RANSK! SLOVENi)! OD 1 DO SREDE 19. STOLETJA, E.S-74 Matajc, 1. (2002): Suše. V: Ušeničnik, B. (ur.): Nesreče in varstvo pred njimi. Uprava RS za zaščito in reševanje, Ministrstvo za obrambo, Ljubljana, str. 297-302. Natek, K. (1987): Suša v Sloveniji. Ujma, 1, 39-46. Nicolich, E. (1882): Cenni Storico-statistici sulie saiine d i Pirano, Trst, 108 pp. Ogrin, D. (1994): Modem Age Climatic Fluctuations in the Area of the Culf of Trieste. Geografski zbornik, 34, 5-80. Ogrin, D. (1995): Podnebje Slovenske Istre. Knjižnica Annales 11, Koper, 320 str. Ogrin, D. (1996): Podnebni tipi v Sloveniji. Geografski vestnik, 68, Ljubljana, 39-56. Ogrin, D. (2002): Podnebje (Slovenije). V: Ušeničnik, B. (ur.): Nesreče in varstvo pred njimi. Uprava RS za zaščito in reševanje, Ministrstvo za obrambo, Ljubljana, str. 29-34. Pahor, M. & T. Poberaj (1964): Stare Piranske soline. Spomeniški vodniki 4, Ljubljana, 175 str. Pristov, J. (1994): Namočenost in evapotranspiracija v Sloveniji. Ujma, 8, 169-173. Pučnik, J. (1980): Velika knjiga o vremenu. Cankarjeva založba, Ljubljana, 366 str. Schiavuzzr, B. (1889): La Malarta in Istria. Atti e me-morie della Societa Istriana di Archeologia e Storia patria, Parenzo. Valvasor, J. V. (1984): Slava Vojvodine Kranjske. Izbrana poglavja. Ljubljana, 1-339. Vrhovec, T. (2002): Padavine (v Sloveniji). V: Ušeničnik, B. (ur.): Nesreče in varstvo pred njimi. Uprava RS za zaščito in reševanje, Ministrstvo za obrambo, Ljubljana, str. 42-46. 74 RAZISKAVE SLADKIH VODA RICERCHE Dl ACQUE DOLCI FRESHWATER RESEARCH « ANNALES ■ Ser, hist. nat. ■ 13 • 2003 • 1 original scientific article UDK 551.312.2:582.623(439) received: 2003-04-18 A PRELIMINARY REPORT ON A NEW TYPE OF FLOATING MIRE FROM HUNGARY Janas NAGY & Zoltän TUBA Department of Botany and Plant Physiology, Faculty of Agricultural and Environmental Sciences, Szent islvan University, Gödöllö, H-2103 Gödöllö*, Pater K. u. 1 E-m a i i: nagyj a n o@ya hoo. com ABSTRACT The authors studied (he vegetation dynamics of Sphagnum dominated mires in the Bereg-piain (northeastern Hungary). The Braun-Blanquet method was applied and a new type of floating mire described. The authors suggest the name "skirt-mire" after its shape and preliminary present it in this paper. This widespread scraw formation process is observable on flooded willow mires, when willow trunks and branches grow long, bushy and hair-like additional roots close to the water surface. In the water, the abundant small floating dead plant debris mat not only with each other but also with the hairy-like willow roots and the plants at the bottom. The succession was very fast on its surface. Key words: Floating mire, scraw, skirt-shaped mire, carr, Sphagnum, Hungarian-plain, temperate climate, continental climate RAPPORT O PRELIMiNARE SU UN NUOVO TIPO Di ACQUITRÍNO FLUTTUANTE IN UNGHERIA SINTESI Gli autori hanno condotto una serie di ricerche fitocenologlche in acquitrini délia pianura di Bereg (Ungheria riord-orientale), nei quali predomina il genere Sphagnum. Con i'applicazione del método di Braun-Blanquet è sfafo descritto un nuovo tipo di acquitrino fluttuante. Gli autori suggeriscono il norne di "acquitrino tendato", vista la sua forma, e nel presente articolo ne danno una descrizione preliminare. In seguito ad allagamento, tutte le specie di salici studiate (Salix cinerea, Salix pentandra, Salix fragilis, Salix alba, Salix aurita ed i loro ibridi) formano radici av-ventizie che crescono sotto la superficie dell'acqua. Su queste lunghe radici ramifícate si depositano enorrni quan-lita di detriti organici provenienti da piante morte, risuitando in una formazione "a tenda" che raggiunge il fondo dell'acquitrino. La successione vegeta le è risultata molto veloce. Parole chiave: acquitrino fluttuante, salici, acquitrino tendato, Sphagnum, pianura ungherese, clima temperato, clima continentale 77 ANNALES ■ Ser. hist. nat. ■ 13 - 2003 • 1 Jrfnos NAGY & Zolsan TUBA: A PRUJ.VilNAIiY REPORT ON A NEW TYPE Of FLOATING MIRE FROM HUNGARY, 77-82 INTRODUCTION There are several types of floating vegetation formation (Sculthorpe, 1985) occurring mainly as a tropical phenomenon known as sudd isadd) or floatant, which according to Scuithorpe {1985) forms in two main ways. Sudd may be pioneered by free floating plants, such as Eichornia crassipes and Pistia stratiotes, whose stolo-niferous habit creates a compact floating mat spreading from sheltered marginal sites out over open water. This mat of living plants and organic debris provides a favourable rooting medium for emergent hydrophytes. Sudd may also develop directly from fringing stands of emergent sedges extending from the shore in calm shallows. The rhizomes and roots do not become anchored in the substrate, but form a stable raft floating at a depth of a few centimetres. By definition of Steffen (1931), the first type is like a successional formation of floating meadow, which develops where the water has steep banks and where the open water surface is gradually overgrown by floating or submerged aquatics. The second type is a simultaneous formation of floating meadow (Steffen, 1931). This can be observed on shallow margins of the water, where rhizomes of waterside plants (e.g. Phragmit.es australis, Typha an-gustifolia, Schoenoplectus lacustris in temperate zone) are creeping on and where rooting in the bottom sediments continues into the open water as a self-supporting rhizome mat (Steffen, 1931; Kulczynski, 1949; Dan-sereau, 1957; Junk, 1970; Sioli, 1975; i.ajer, 1998; Ba-logh, 2000a, b). However, data on the floating mire formation in Sphagnum dominated mires under temperate, continental conditions are sparse. During our phytocoenological research between 1992 and 2002 on the Sphagnum dominated mires of the Northeast Plain in the continental temperate climate in Hungary we observed many similar and some different (and hitherto undescribed) processes of floating mire formation, which can also be found in other parts of Hungary. In this preliminary paper we present till now undescribed but widespread floating mire type. MATERIAL AND METHODS The study site The investigated mires (Bence-to 48°8'55" N, 22° 25'35" E; Nyires-to 48*11'3" N, 22*30'6" E; Navad-patak 48"10'32" N, 22*30'45" E; Bab-tava 48-11'16" N, 22°29'0" E; Zsid-t6 48'11 '87" N, 22°29'6" £) lie in the northeastern corner of the Great Hungarian Plain in Hungary on the Bereg-Szatmar Plain in Bereg-Szatmar County (East-Central Europe). These mires belong to the Samicum plant-geographical region. The mires have formed in abandoned riverbeds (silted oxbows), in a ring indicated by Beregdaroc, Gelenes, Takos, and Csaroda villages (Eig. 1). The fieldwork has been carried out since 1994. In the Koppen (1923) system, the climate of the study area is Cbfx (between moderate warm and moderate cool). The mean annual number of sunny hours is ca 1950, while the annua! mean temperature oscillates between 9.4 and 9.5 °C. Yearly precipitation is 630-660 mm, with 370-380 mm during the growing season (Ma-rosi & Somogyi, 1990). The distribution and amount of precipitation and the ground water level can vary greatly in successive years. Methods The Braun-Blanquet method (1951) was used to describe the vegetation dynamics. In the sample plots, species by species on a percentage scale was estimated in the case of higher plants in all of the associations. In the middle of the flooded willow and alder carr, we could proceed only on foot, swimming or by mud-walking. We used an Irish word, "scraw", for floating mires. The coenoiogical examinations were made in this way, which provided an opportunity to observe the mechanism of formation of the scraw. The size of the scraws was estimated by eye. Here we give the relevant interpretation of our observations. Taxoriomical and syntaxonomical nomenclature follows Simon (1992). RESULTS AND DISCUSSION After natural or artificial floods, the peatmoss cushions were submerged in base-rich water and failed to survive. On these former peatmoss mires secondary scraw formation processes could be observed, whose first stage was named "skirt-mire" after its shape. They develop as follows (Fig. 2): all the willow species (Sa/fx cinerea, S. pentandra, S. fragilis, S. alba, S. aunta and their hybrids) that can be found in the examined areas are able to develop adventitious roots from their shoots near the water surface after flooding. Root formation is independent of the age of the shoots of the willow species (Fig. 3). The dead broken fragments of plants floating in large quantities in the mire water mat with each other, with the long and bushy hair-shaped willow roots of stem origin and with the plant residues at the bottom of the lake. Thus a matted carpet forms, which falls as a "skirt" from the water surface to the bottom of the lake. The broken fragments deposited in the water enlarge mainly the bottom of the skirt, as the movement of the water erodes more strongly the parts near the water surface. In the first summer of their formation, the thickness of the skirts near the surface are therefore only a half to a third (20-30 cm) of that at the bottom of the bed (40-70 cm). These skirts average 3-6 m in diameter in the areas examined around individual Salix cinerea shrubs. 78 ANNALES ■ Ser. hist, nat • 13 • 2003 • 1 ïâ'nos NAGY & Zoiláll TOBA: A PREilMINARV REPORT'ON A NEwTyPE Of FLOATING MIRE FROM HUNGARY, 7>'-82 The location of the Bereg-pUdn in Hungary i Gefênes i P'.'.üM ^ [ [i'L'Kj-: r' of HtrrÇiiîy 4 oí cû\ifi(:i*î, ES) M™ river&and l.ik-ta , v ■, J '//'■■ ______________= P 't- -\V V Bâb-tava mire j - ■ .- J;^ i ¿AV ¡^ ¡: ......................~ i Beregdaróc 1 "V, • P,- * "Èl ^- v f''¿ftiyies i.ô m re I i y CSsT1' .......Navad-patak mire ! v-r ^ Csaroaa ^ , V"-;r" , « -¿S..'-............- W^-V. j v i ^ The location of the investigated mires on the Bereg-plain itjïufa îï; mfîa rewiVTOja« med/ .s róc/o ! Vásárosnamény Fig. 1: Location of the studied area. 5/. 1: Lokacija preučevanega območja. The skirts can be formed around numerous willows as well, forming several ten square metres large scraws. Such mat-like scraws can be observed in the dense Glycerietum maximae among the leaves of the bottom rooted Glyceria maxima specimens of the stands. Water under the skirt: is much colder than around it. The first colonists that can be found on the surface of the seraw include Cicuta virosa, Carex pseudocyperus, Galium patustre, Lycopus europaeus, Poa paiustris, Glyceria maxima, Thelypteris paiustris, Polygonum lapathifolium or Typha latifolia, Typha angustifolia, as well as drifted Salvinia natans, Hydrocharis morsus-ranae, Lemna minor and sometimes Stratioies abides, and Oenantbe aquatica. Sometimes, Cicuta virosa and Glyceria maxima may be missing from these bare surfaces in the first year. In the second year, the Cicuto-Caric.etum pseudocy-peri becomes almost predominant on the skirt-mires, but its dominance decreases gradually in the next few years. For a few years, rhizomatous, emergent species, mainly Glyceria maxima, Thelypteris paiustris, and Lythrum salicaria and occasionally Comarum palustre will be dominant (Tab. 1). The plants of the initial state can be seen just on the growing edge of the scraws. Concentric structure of the floating mire develops. CONCLUSIONS The skirt-mire formation briefly outlined above has not been described yet in literature, although it can be observed in Hungary in many willow swamps flooded with water, and it is probably widespread where conditions (willows, water flooding, floating plant debris suitable for matting) are suitable. We found similar processes near the study site in Bodrogkóz, NE Hungary, It is worthy of note that scraws can be formed in any place where peat form-ing-piants are able to settle, survive and propagate on living or lifeless substratum on the surface of the water. 79 ANNALES • Ser. hist, nat. • 13 • 2003 • 1 Janos NACY S- Zoltan TUBA: A PRELIMINARY REPORT ON A NEW TYPE OF FLOATING MIRE FROM HUNCASY, 77-82 Fig. 2: Scheme of the formation and the succession of the skirt-mires in their first four years in Bence-tô mire, NE Hungary, between 1998-2002. Si. 2: Shema nastajanja in sukcesije "zavesastih" barij v prvih štirih letih. Barje Bence-t6, SV Madžarska, med letoma 1998 in 2002. 80 ANNALES • Ser. hist, nat. • 13 • 2003 • 1 linos NAGY & Zollán TUBA: A PRELIMINARY REPORT ON A NEW TYPE OF FLOATING MIRE FROM HUNGARY. 77-H2 Tab. 1: Phytosociological relevés of different skirt-mires (Bereg-plain, NE Hungary). Tab. 1: Fitosociološki popisi različnih "zavesastih" barij (pusta Bereg, SV Madžarska). ¡Place of samples Navad-patak mire Žsid-to rnire | Bence-tó mire Date 17.07.1997 17.07.1997 29.07.1999 29.07.1999 29.07.1999l14.07.2000 14.07.2000 i Age of the skirt-mire ~ 3 years ~ 3 years ~ 5 years ~ 5 years - 5 years j ~'¿ years ~ 2 years Plot size 9 mJ 9 m^ 25 nrr 25 nr 25 nr I 9 nrr 9 nr Cover (%) Shrub level Salix pentandra 2 40 í'rangula alnus 3 Salix cinerea 40 25 90 5 10 3(dead) 5 (dead) Herb level Bidens cernua 40 Carex pseudocyperus 1 5 10 Ca rex riparia 1 Cicuta virosa 7 10 40 Cosvarum palustre 5 Galium palustre 1 1 Glyceria maxima 5 1 7 3 5 Hydrocharis morsus-ranae 2 3 S 70 7 Lemna minor 0.1 10 40 20 iythrum salicaria 30 Lycopus europaeus 0.1 20 1 Lvsímachia vulgaris 2 0.5 0.1 Oenanthe aquatica 1 7 Polygonum lapathifolium 20 \Salix cinerea 1 Sa/vjn/a natans 2 2 5 ¡Scutellaria galericulata 10 |Solanum dulcamara 3 2 jSparga¿ifi/m erecium 1 5i rati of es al bides 1 Thelypteris palustris 13 40 90 0.1 Typha angustifoiia 90 10 Typha latifolia 4 10 Utricularia vulgaris 70 The vegetation changes of the skirt-mires are very quick and to a great extent conditioned by the rhythm and rate of the water supply (Nagy, 2002). The water retention peat forming process takes place on terrestrial rnire in dry periods and on floating mires in wet periods. When developing an adequate peat thickness, it can counterbalance the effect of fluctuation of the water supply under the established plant communities. ACKNOWLEDGEMENTS The authors are indebted to Prof. Dr. Michael C. F. Proctor and Dr. Marton Baiogh for their useful advice and suggestions and to Mrs. Katalin Reti for checking Fig. 3: First phase of the skirt-mire formation; branches the English text. Financial support by the Directorate of of Salix cinerea develop adventitious roots (Bence-to the Hortobagy National Park (Debrecen) is acknowl-mire, NE Hungary, 30 March 2000). (Photo: j. Nagy) edged. SI. 3: Prva faza oblikovanja "zavesastega" barja: veje vrste Salix cinerea razvijejo adventivne korenine (barje Bence-to, sv Madžarska, 30. marec 2000). (Foto: ). Nagy) 81 ANNALES • Ser. hist. nat. • 1.3 • 2003 • 1 linos NAC Y & Zolíín TUBA: A PRELIMINARY REPORT ON A NEW TYPE OF FLOATING MIRE FROM HUNGARY. 77-02 PRELIMINARNO POROČILO O NOVEM TIPU "ZAVESASTEGA" BARJA NA MADŽARSKEM jános NAGY & Zokán TUBA Department of 8otany arid Plant Physiology, Faculty of Agricultura! and Environmental 5cier¡ces, Szent ístván University, Gödöllö, H-2103 Gödöllö, Páter K. u. 1 E-mail: nagyjatio@yahoo.com POVZETEK Med letoma 1992 in 2002 sta avtorja opravila vrsto fitocenoloških raziskav barij s prevladujočim šotnim mahom Sphagnum (Nyfres-tó, Báb-tava, Navad-patak, Zsid-tó in Bence-tó) v madžarski pusti Bereg. V omenjenem obdobju sta preučevala doslej neopisani in v tem članku preliminarno orisani proces oblikovanja tako imenovanega "zave-sastega" barja, potem ko je bila naravno ali umetno poplavljena njegova vrbovina. Vse preučevane vrste vrb (Salix cinerea, S. pentandra, S. fragilis, S. alba, S. aurita in njihovi hibridi) po poplavljenju poženejo adventivne korenine iz svojih poganjkov pod vodnim površjem. Oblikovanje korenin je neodvisno od starosti poganjkov in vrste vrb. Na teh dolgih, košatih, lasastih koreninah se v vodi odmrli delci rastlin v velikih količinah prepletajo in spajajo med seboj, z vrbjimi koreninami steblastega izvora in z rastlinskimi ostanki na vodnem dnu. Tako se oblikuje nekakšna "zavesa", ki s korenin, rastočih iz vrb jih stebel na vodnem površju, pada vse do vodnega dna. Med prvimi naseljenci, ki jih je mogoče najti na površju zavese, so Cicuta virosa, Carex pseudocyperus, Galium palustre, Lyco-pus europaeus, Poa palustris, Glyceria maxima, Thelypteris palustris, Polygonum lapathifolium ali T. latifolia, Typha angustifolia kot tudi Salvinia natans, Hydrocharis morsus-ranae, Lemna minor ter včasih Stratiotes aloides in Oe-nanthe aquatica. V prvem letu lahko s teh golih površij izgineta Cicuta virosa in Glyceria maxima. V drugem letu poslane Cicuta virosa skorajda dominantna vrsta v teh "zavesastih" barjih, vendar se njena prevlada v naslednjih nekaj letih sčasoma zmanjša. Takrat začnejo prevladovati plezajoče (rizoidne) vrste (Glyceria maxima, Thelypteris palustris, l.ythrum salicaria in Comarum palustre,). Rastline v začetnem stadiju je mogoče videti le na rastočem robu zaves, in v barju se začnejo oblikovati koncentrične strukture. Vegetacijske spremembe v "zavesastih" barjih so zelo hitre ter močno odvisne od ritma in stopnje vodnega dotoka. Ključne besede: "zavesasto" barje, vrbovina, Sphagnum, madžarska pusta, zmerna klima, celinska klima REFERENCES Balogh, M. (2000a): Classification of mires. In: Szurdoki, E. (ed.): Sphagnum dominated habitats in Hungary. Research, Managemant, Conservation. CEEWC8, Munkac-soport, Miskolc, p. 57-65. Balogh, M. (2000b): The problems of the succession of floating mires I. Kitaibelia, 5, 9-16. (in Hung, with Eng. Summary) Braun-Blanquet, J. (1951): Pflanzensoziologie. (Plant-sociology). Springer Verlag, Wien. Dansereau, P. (1957): Biogeography. An ecological perspective. The Ronald Press Co., New York, junk, W. (1970): Investigation on the "Floating Meadows" (Paspalo-Echinochloetum) on the middle Amazon. Part 1. The Floating vegetation and its ecology. Amazo-niana, 2, 449-495. Koppen, W. (1923): Die Klimate der Erde. Walter de Gruyter, Berlin. Kuiczynski, S. (1949): Peatbogs of Polesie. Memories de L'Acadernie Polonasie des Sciences et de Letters, Cra-covie. Lâjer, K. (1998): Bevezeîés a magyarorszâgi lâpok vegetaciô ôkoiôgiâjâba. (Introduction to the vegetation-ecology of the Hungarian mires).Tilia, 6, 84-238. (in Hung.) Marosi, S. & S. Somogyi (1990): Magyarorszag kistajai-nak katasztere. (Cadaster of microregions of Hungary) MTA Fôldrajztudomânyi Kutato Intézet, Budapest, (in Hung.) Nagy, (2002): Research of syndsnamical processes for conservation of natural values of a Sphagnum mire. Ph.D thesis, Gôdôllô. (in Hung, with Eng. Summary) Scuithorpe, C. 0. (1985): The Biology of Aquatic Vascular Plants. Konigstein: Koeitz Scientific Books. Simon, T. (1992): A magyarorszâgi edényes flora hatâ-rozoja. Harasztok - virégos nôvények. (Handbook of the Flungarian vascular flora).Tankonyvkiadb, Budapest, (in Hung.) Siolî, H. (1975): Tropical river: the Amazon. In: Whit-ton, B.A. (ed.): River Ecology. Blackwell Science Publications, Oxford, London, Edinburgh, Melbourne. Steffen, H. (1931): Vegetationskunde von Osteuropen. (Vegetation science of East-Europe.) Gustav Fischer Verlag, jena. 82 ANNALES • Ser. hist, nat. • 13 • 2003 • 1 original scientific article UDK 582.26(282.24 Dragonja) received: 2003-01-25 ALGAE IN DRAGONJA RIVER Aleksandra KRIVOGRAD KLEMENČIČ SI-1290 Grosuplje, Čušperk 51 Danijel VRHOVŠEK limnos ci.o.o., SI-1000 Ljubljana, Podlimbarskega 31 E-mail: info@limnos.sf Gorazd KOSI Nacionalni inštitut za biologijo, SI-1001 Ljubljana, Večna pot 1 11 ABSTRACT Between 1998 and 2000, peryphytic algal communities were sampled and analysed at five sampling sites on the Dragon/a river and at a single site on the tributary Pinjevec. Altogether, 238 algal taxa were registered, with prevailing Bacillariophyceae (170), while 38 taxa belonged to Cyanophyceae and 17 to Chlorophyceae. Of all 238 taxa, 65 were recorded for the first time in Slovenia, 13 belonging to Cyanophyceae and 52 to Bacillariophyceae. Most of these 85 taxa were recorded in the Dragonja estuary. Key words: algae, streams, springs, brackish waters, southwestern Slovenia ALGHE NEL FIUME DRAGOGNA SINTESI Tra il 1998 ed il 2000 sono state campionate ed analizzate cornunità perifitiche algali in cinque stazioni di cam-pionamento nel fiume Dragogna ed una stazione neI tributario Pinjevec. Sono stati trovati 238 taxa algali. II con-tributo maggtore proviene dalla famigUa delie Bacillariophyceae (170 specie); 38 taxa apparíengono alie Cyanophyceae mentre 17 alie Chlorophyceae. Tra i 238 taxa, 65 sono nuove segnalazioni per la Slovenia, tra le quali 13 Cyanophyceae e 52 Bacillariophyceae. La maggioranza di questi taxa è stato campionata nelPestuario del fiume Dragogna. Parole chiave: alghe, corsi d'acqua, sorgenti, acque salmastre, Slovenia sud-occidentale 83 ANNALES ■ Ser. hist. nal. • T 3 ■ 2003 • 1 Aleksandra KRjVOCRAD KLEMENČIČ et ¿1.: ALGAE IN DRAGONJA RIVER, 83-90 INTRODUCTION The biodiversity of algae in Slovenia is relatively high, as more than 2000 different algae species have been recorded so far (Kosi & Vrhovsek, 1996). The issue of the endangered algal species, threatened by the endangered water ecosystems, has not been clarified as yet due to the lack of investigations. Drastic changes usually occur during the regulation of rivers and streams, when the fundamental ecological conditions are changed (the substrate, water current, light); the consequences are of course reflected in the species' reduced diversity. Similar results can be seen in polluted waters, where the number of species decreases from the sources towards estuaries of the water courses (Vrhovsek et. a/., 1983). Most of the Slovenian water-streams are already polluted (Vrhovsek et al., 1983, 1994; Krivograd, 1997; Krivograd Kle-menCi£, 2001; Smolar, 1997). The Dragonja is one of the very few unpolluted Slovenian rivers. The water at its estuary is brackish. The algae occurring in Slovenian brackish waters have not been studied so far. With a view to protect its natural ecosystems with all its constituent parts, including algae, the Dragonja river valley is planned to be given the statLis of a landscape park. It is necessary to conserve the high diversity of algal species, and the rare species, which cannot be found in other Slovenian rivers due to the Dragonja's very special ecological conditions (flysch landscape, brackish water). The purpose of this research was to determine the species composition of algal communities in the Dragonja river, from its source to estuary and in its tributary Pinjevec. The only data on the algal species concerned the lower part of the river at Kastel (in "The research of the quality of surface waters in Slovenia in 1992", Zupan (ed„ 1994)), where the sampling site of the Hydro-Meteorological Institute of Slovenia is situated. However, no research has been carried out concerning the algae of the upper part of the Dragonja river and its tributaries. At the sampling site in the Dragonja esUtary, the water is brackish. On this occasion let us add that no investigations concerning the brackish waters of Slovenia had been carried out prior to this research. MATERIALS AND METHODS Description of sampling sites The sampling sites are presented in figure 1 and their description given in Table 1. The sampling sites C, D and E are located close to each other. They differ mainly in the speed of the water current. The sampling site 8 is located in the tributary Pinjevec, just before it joins the Dragonja river. Tab. 1: Description of sampling sites on Dragonja river and its tributary Pinjevec. Tab. 1: Opis vzorčnih mest na reki Dragonji in pritoku Pinjevcu. Sampling sites Shading of the riverbed Speed of water-current Riverbed width (m) Co-ordinates (after Gaus-Kriiger) A-source shaded fast t X-5039250 Y=5412000 8-Skrlirte partly shaded changing 15 X=5037125 ¥=5402750 C-pool partly shaded very slow 10 X=5396825 Y=5034175 D-slow current shaded sfow 12 X=$03400Q Y=53%750 E-strong current not shaded fast 7 X=5396825 Y=-5034175 F-estuary not shaded sfow 20 X=S390S25 Y=5037250 The samples were collected seasonally during the years 1998, 1999 and 2000 (10. 7. 1998, 18. 7. 1998, 23. 8. 1998, 20. 3. 1999, 29. 7. 1999, 18. 10. 1999, 17. 1. 2000) at all sampling sites, five periphyton samples were taken at each sampling site for qualitative analysis by scratching the surface of gravel, rocks, macrophytes, wood and other submersed materials (glass and plastic bottles, iron sticks, etc.) The phytoplankton was sampled using the plankton net with mesh size 25 }Lm at the estuary. The fixation of the samples was done in situ with 4% formalin concentration. For diatom determination, samples were pre-treated with saturated HN03 (APHA, 1985). Fig. 1: Map of the river Dragonja and its tributary Pinjevec. Legend1; A - source, B - Škrline, C - pool, D -slow current, £ - strong current, F - estuary. SI. 1: Zemljevid reke Dragonje in pritoka Pinjevca. Legenda: A - izvir, B - Škrline, C - tolmun, D - počasi tekoča, E - brzica, F - izliv. 84 ANNALES • Ser. hist nat. ■ 13 • 2003 • 1 Aieksandra KRIVOGRAD KIEM£nCiČ nt ni: AIGAE IN DRAGONJA RIVER. 83-90 The algal samples were determined in the laboratory using the light microscope (magnification lOOOx). The relative frequency of most common species was evaluated using the numbers from 1 - single, 2 - rare, 3 -common, 4 - frequent and 5 - dominant. The algae were determined using the following identification monographs: Lazar, 1960; Starmach, 1966, 1972; Hindak ef a/., 1978; Krammer & Lange-Bertalot, 1986, 1988, 1991a, 1991b; Popovsky & Pfiester, 1990; Cvijan & Blazencic, 1996; Hindak, 1996. RESULTS AND DISCUSSION At the five sampling sites on the Dragonja river and at the single site on its tributary Pinjevec, 238 (Tab. 2} algal taxa were established (with their composition presented in figure 2). In view of the number of species, Bacillario-phyceae dominated at all sampling sites, followed by Cyanophyceae. A similar situation was recorded in the river Branica flowing on flysch ground (Smolar, 1997). Cyanophyceae were followed by Chiorophyceae at sampling sites A, C, D and F, and by Zygnematophyceae at sampling sites B and E. Zygnematophyceae were not found at sampling site A. Euglena sp. was recorded at sampling site D. The species Peridinium umbonatum was found at sampling site 8, and Peridinium hi pes at sampling site F. The species Dinobryon sertularia was found at sampling sites 8, C, D and E, All four species are pianktonic. The species Batrachospermum vagum was registered at sampling site E, and Audouinelia chalybea at sampling site F. The total number of different taxa at sampling site A was 62 (Tab. 2). In all five periphyton samples taken at sampling site A, the following species were found: Achnanthes minutissima, Amphora ovalis, Diploneis ellip-tica, D. oblongeila, Gomphonema angustatum, G. angusturn and Nitzschia linearis var. linearis. The most common species were Achnanthes minutissima and Gomphonema angustatum. Achnanthes flexella, Cym-hella amphicephala var. amphicephala, Diploneis ellip-tica, Gomphonema angusturn and Cymbeila descripta are characteristic oligotrophy water species, Surirella spiralis is a widespread species, characteristic of the river springs and takes with limestone ground, containing mid-to high- levels of electrolytes (Krammer & Lange-Bertalot, 1988). The species Caloneis alpestris, Cymbeila ehren-bergii, C. tumidula and Nitzschia angustatula are widespread and characteristic of karst waters rich in calcium (Krammer & Lange-Bertalot, 1986, 1988). At sampling site B, the total number of different taxa was 116, at sampling site C 105, at sampling site D 89, and at sampling site E 94 (Tab. 2). Although the water current was quite different between the individual sampling points, the composition of the algal species did not differ much. O Zygnematop liyceae £3 Ohio rop iiyceae BGugtenophyceae SDinophyceae E3 Baci llariopliyccac EiCJirysophyoeae □ Floridcophyceae 0 Cyanophyceae Fig. 2: Algal community structure in the river Dragonja and its tributary Pinjevec during the years 1998, 1999 and 2000 (A - source, B - Škrline, C - pool, O - slow current, E - strong current, F - estuary). SI. 2: Sestava algne združbe v reki Dragonji in v pritoku Pinjevcu V letih 1998, 1999 in 2000 (A - izvir, B -Škrline, C - tolmun, D - počasi tekoča, E - brzica, F ~ izliv). The changes in biornass along the current occurred mainly because of the differences in the pH values, temperature, water level and the nitrate concentration (Sza-rek, 1994). Light has a greater impact on the composition of periphyton than the water current, level and nitrate concentration (DeNicoia & Mcfntire, 1990). In all five periphyton samples taken at sampling sites B, C, D and E, the following species were found: Achnanthes flexella, A. minutissima, Anomoeoneis vitera, Cymbeila affinis, C. cymbiformis, C. microcephala, Den-ticula kuetzingii, Eunotia arc.us, Fragilaria biceps and Gomphonema angusturn. The most abundant species were Achnanthes minutissima, Cymbeila affinis and C. microcephala. The species Rivularia haematites, which can be found in stagnant and running waters on limestone (Starmach, 1966), was present at sampling sites B, C and E. On the same substrate, Amphipleura pellucida, Caloneis alpestris, Cymbeila laevis and Tolypothrix cacullata are also widespread (Starmach, 1966; Krammer & Lange-Bertalot, 1986, 1991a). Batrachospermum vagum, a characteristic oligotrophy water species (Hindak ef ai, 1978), was found at sampling site E during the summer 1998. At sampling sites B, C, D and E, Dinobryon sertularia was present, while at sampling site B Peridinium umbonatum was established. Both species are characteristic of plankton (Hindak ei ai, 1978). The presence of plankton species in the rivers depends on the water retention time in stagnant places. The high species diversity was found at sampling site F - the Dragonja river estuary. The total number of different ptanktonic and periphyton species was 121 (Tab, 2). By their nature, estuaries are generally eutrophic and dynamic systems. Consequently, the number of species M0 J 20 21 00 I 80 i m I 40 20 o A B C D E F sampling sites 85 ANNALES - Ser. hist. nal. • 13 • 2003 • 1 Aleksandra KRiVOCRAD KLEMENČfČ el ni: ALGAE IN DRAGONJA RiVER, 83-90 Tab. 2: List of algal species occurring in the river Dragonja and its tributary Pinjevec during the years 1998, 1999 and 2000. Legend: 1 - single, 2 - rare, 3 - common, 4 - frequent, 5 - dominant species; A - source, B - Škrline, C -pool, D - slow current, E - strong current, F - estuary. Tab. 2: Vrstna sestava alg v reki Dragonji in v pritoku Pinjevcu v letih 1998, 1999 in 2000. Legenda: 1 - posamična, 2 - redka, 3 - običajna, 4 - pogosta, 5 - dominantna vrsta; A - izvir, B - Škrline, C - tolmun, D - počasi tekoča, E -brzica, F - izliv. Taxon Sampling sile A ß C D E F | PROKARYOTA CYANOPHYTA CYANOPHYCEAE *Borzia triloculans Cohn 1 1 1 1 Calothrix parietina (Naegeli) Thurel 1 Calothrix sp. 1 1 Dactylococcopsis rhaphidioides 5 Hansg. *Cloeocapsa bituminosa (Bory) Kuetz. 1 1 Gtoeocapsa montana Kuet2. 1 Gloeocapsa túrgida (Kuet2.) Holler. t 1 i 1 Lyngbya cryptovaginata Schkorbatoff 1 *Lyngbya perelegans Lemrn. 1 Merismopedia glauca (Ehten.5 Naegeli 1 1 1 1 Merismopedia punctata Meyen 1 1 1 Nostoc paludosum Kuetz. 1 1 1 Nostoc sp. ! *Oscillatoria ¡aetevirens ÍCrouan) 1 Comont Osci//a(0fia okenii Agattih 1 Oscillatoria subcapitala Portomarenko 2 Phormidium arnbigmim Gomonl 1 'Phormidium angustissimum W. & 1 3 3 2 G.S. West Phormidium autumnale {Agardh) Co- 1 2 1 2 1 1 mont *Phormidium dimorphum Lemin. 1 Phormidium foveolarum (Mont.) Co- 2 mont Phormidium fragtle (Menegh.) Co- 2 mont Phormidium retzii (Agardh) Gomont 1 1 t 1 Phormidium sp. 1 1 1 1 1 i Pleclonema sp. 1 'Pseudanahaena papillalenninaia 3 3 1 3 1 (Kiss.) Kukk *Pseudospirulina amoena Parskow & 1 Jahnke Rhabdoderma lineare Schmidle & 1 lauter. Rivularia haernatites (D.C.) Agardh 2 3 3 *Schizothrix friesii (Agardh) Comont 1 2 Schizothrix lateritia (Kuetz.) Comont 2 1 1 Schizothrix sp. 1 Spirulina maior Kuetz. 1 Spirulina sp. ? "Spirulina tenuissima Kuetz, 1 Synechococcus cedrorum Sauvageau 2 2 1 1 *Synechocystis septentrionalis Skuja ! *Tolypothrix cucullata jaag 3 1 3 2 EUKARVOTA RHODOPHYTA FLORIDEOPHYCEAE Aiidouineifo chalybea (Lyngbe) f nos I Batrachospermum vagum (Roth.) 1 Agardh HETEROKONTOPHYTA CHRYSOPHYCEAE Dinobryon seriularia Ehren. 1 1 ! t BACILLARtOPHYCEAE Achnanthes deticatula (Kuetz.) Grun. 1 Achnanthes flexella (Kuetz.) Brun 1 3 3 2 2 I Achnanthes taevis Oestrup 1 1 Achnanthes lanceolata s^p.lanceolata 1 var.lanceolata (Rreb.) Crun. Achnanthes rniriulissima Kuetz. 5 5 5 5 4 3 *Achnanthes septata A. Cleve 5 Achnanthes sp. 1 1 1 Amphipleura pellucida (Kuetz.) Kuetz. 1 1 *Amphora angusta (Greg.) Cleve 3 Amphora coffeaeformis (Agardh! 1 3 Kuetz. Amphora libyca Ehren. I 1 Amphora montana Krass. 3 1 1 Amphora ovalis (Kuetz.) Kuetz. 1 1 1 ) 1 Amphora pediculus (Kuetz.) Grunow 1 Anomoeoneis vitrea (Grun.) Ross 2 3 3 3 1 Aulacoseira grarmlata (Ehren.) Simon. } *Bacillaria paradoxa Cftaiin 1 1 Caloñéis alpestris (Grun.) Cleve I 1 1 3 1 1 Caloñéis bacillum (Grun.) Cleve 1 *Caloñéis molaris (Crun.) Kramm. ? 1 CaloneÍ5 pulchra Messik. 1 Caloñéis schumanmana (Grun.) Cleve 1 Caloñéis silicula i silicula (Ehren.) ? Cleve Caloñéis tennis Greg. 1 Cocconeis pediculus Ehren. 2 Cocconeis placeiitula Ehren. 1 3 Cychtella oceüata Panto. I 1 Cyelote!la sp. I 1 ] 1 1 *Cymatopteura solea var. apiculata t 1 (W.SmitW Ralfs Cymbella affinis Kuetz. 1 S S 5 1 Cymbella amphieephala var. amphi- 1 1 3 S 1 1 cephala Naegeli *Cymbella caespitosa (Kuetz.) Brun 1 Cymbella cesatii (Raben.) Grun. 2 3 3 2 CyrnteZ/a cistula (Ehren.) Kirch. 2 t t 1 Cymbella cymbiformis Agardh 2 2 1 1 CymbeUa delicatula Kuetz. 3 1 1 1 *Cymbe/la descripta (Hust.) Kramm. & 1 ! 2 2 1 Lau.-Bert CymbeUa ehrenbergii Kuetz. 1 Cymbella hélvetica Kuetz. I t Cymbella incerta (Crun.) Cleve 1 Cymbella laevis Naegeü 2 1 1 CymbeUa microcephala Grun. 3 3 3 4 3 1 Cymbella prostrata (Berk.) Cleve 1 1 1 t "Cymbella pusilla Grun. 1 1 1 t 3 86 ANNALES • Ser. hist, nat. • 13 • 2003 • 1 Aleksandra KRiVOCRAD KIEMENCIČ et Cymbeila rupicota Grun. 2 ] 1 1 1 Cymbella silesiaca Bleiscli 1 2 2 2 2 1 Cymbeila sinuata Greg. 1 S 1 Cymbella subaequaiis Grun. 4 ! 1 3 5 Cymbeila túmida m V■,■■. V Vsi! Otf-.ift.'Ä?, S6" N ^--j^^äiL A. •••Afi^V" "H- "Niv • - Ab;atfi i _- Braäanaj 6--- ■ V» \ ^ - 1' i A e\s ■fi^J / Y y - r - ' ■■■-■■■ % iilx^oni. ui. . -ffneif-i ■ " \ 01 en er> in « oo — w cy n trj o w Date Fig. 2: Daily discharges and precipitation in the September - November 2001 period. SI. 2: Dnevni pretoki in padavine v obdobju September - november 2001. The previous period of summer 2001 was exceptionally dry and for that reason the first rainfall in the beginning of September, which exceeded 20 mm, was not reflected in the increase of the discharge. Due to the interception on the vegetation cover, enlarged évapotranspiration and the filling in of soil moisture deficit the ef- j i it-' (Movras] 100 — -Q (Brae -sftare of Mlifii in Sfaiaofl Date Fig. 3: The share of Mlini springs in the total discharge of the Bracana stream. Si. 3: Delež izvirov Mlini v skupnem pretoku Bračane. A comparison of shares of discharge of the Mlini springs in the total discharge of the Bračana at the Abrami station is also interesting. In figure 3, these 95 ANNALES • Ser. hist. nat. • 13 ■ 2003 • t ¡arija KOCOVSEK ol si: HYOROCHEMICAI RESEARCH OE THE MUNI SPRINGS, SSTRSA. 91-102 shares are represented during both most intensive precipitation events. The considerable decrease in the share of the Mlini spring just before the rise of discharges indicates that the surface Bracana stream with its flysch recharge area reacts characteristically faster to precipitation than the Mlini karst spring. We may also find out that within a longer period of dry weather the Mlini spring represents the principal source of water in the Bracana stream (around 50%). We may thus conclude that the selected two-month period of monitoring physical and chemical characteristics of the Mlini spring proves to be of hydrological interest primarily due to the possibility of observing the reactions of the spring and the surface stream to the first precipitation after the prolonged period of dry weather. MATERIAL AND METHODS At the Mlini karst spring we also conducted, between 11 September and 14 November 2001, a two-month detailed monitoring of the composition of its water. Thus we covered a short period of low waters that was followed by a brief yet intensive precipitation forming water waves, as well as longer period of recession and a longer period of reestablishment of stable conditions. Tab. 3: The applied methods of analyses are ISO methods (10253:1994; 7888:1985; 5813:1983; 5815:1989; 9963-1:1994) (APHA, 1995), and DIN 38409 HI8 method. Tab. 3: Uporabljene ISO metode (10253:1994; 7888:1985; 5813:1983; 5815:1989; 9963-1:1994) (APHA, 1995) in DIN 38409 HI8 metoda. Indicator Method Detection limit temperature ♦St.Meth. 2550 B. pH ISO 10253:1994. Conductivity - SEC ISO 7888:1985 1 |-iS/cm turbidity turbidimetrical 5 mgSiOa/l dissolved oxygen ISO 5813:1983 0.01 mgOj/l BOD, ISO 5815:1989 0.01 mg03/l COD - permanganate method according to Kubel Tiemann 0.01 mg02/J alkalinity ISO 9963-1:1994 0.002 mmol CaC03/l chlorides St. Meth.4500-CI B. argentometric 0.1 mg/l sulphates St. Meth. 400-SO« E. turbidimetric 1 mg/l hardness - total St. Meth. 2340 C. complexometric (EDTA) 0.002 mmol CaCO,/! total solids dried at 105 °C St. Meth. 2540 B. gravimetric 0.001 mg/l total suspended solids dried at 105 °C St. Meth. 2540 D. filtration through CF 45 }im, gravimetric 0.001 mg/l ammonia spectrophotometric with fenoiate hypocbloritome 0.001 mgN/l nitrites St. Meth. 44500-N0j B. spectrophotometric with a-naftilamine and sulfinic acid 0.001 mgN/l nitrates St. Meth. 4500-N03 B. 0.0T mgN/l organic nitrogen St. Meth. 4500-Notr B. digering in the acid media, spec-trophotometrical as ammonia 0.OO1 mgN/l ortho-phosphates St. Meth. 4500-P E. s pectro photo metrical with ammonia-molibdate and ascorbic acid 0.005 mgP/l total phosphorus digering, followed by a procedure as with ortho-phosphates 0.005 mgP/l oil and grease, mineral oils DIN 38409 H18 0.002 mg/l Mn, Cu, Cr, Pb AAS - flameless technique (graphite) 1 fiR/i Cd AAS - flameless technique (graphite) 0.1 pg/i K, Na, Ca, Mg AAS ~ flame technique 0.1 mg/l Zn AAS - flame technique 5 MR/I f-e AAS - flame technique 10jtg/l |TC, FC, FS MF technique, selective bases, number/100ml aerobic mesophile bacteria N/37 _nutmrta£ar_37JC, number /ml 96 ANNALES • Ser. hist. »at. • 13 ■ 2003 • 1 Janja KOGOV5EK Li. 0 - FS ..........N/37" ......................Q ^ 2001 Ê o 0 S. 9. 16. S. 20. S. 6, 10. 18. 10, 26, 10, 5, 11, 15. 11. 25. 11. Fig. 9: Mlini spring: faecal streptococci (FS) and aerobic mezophile bacteria (N/37) in autumn 2001. SI. 9: Izvir Mlini: fekalni streptokoki (FS) in aerobne mezofilne bakterije (N/37) jeseni 2001. These findings indicate a great importance of detailed observations of the springs, particularly during the periods of intensive precipitation when greater variations also occur, which cannot be perceived by regular monitoring with less frequent measurements. Comparison of the results with the measurements carried out within the framework of the national monitoring of the Republic of Croatia The Mlini spring has been included in the Croatian national monitoring network since 1996. Since then the monitoring has changed a great deal, both in the extent of parameters and in the frequency of measurements and analyses. As far as the springs on the Istrian peninsula are concerned, there has been an increase in the number of parameters by means of which the samples of water were analysed, whereas the number of sample collection has fallen. : If we compare the minimal, maximal and mean values for the year 2000, when most sample collections were carried out (12), with the frequent sampling conducted from September to November 2001, we can notice that the majority of the parameter values from the detailed observations of the autumn 2001 actually fall into the range of measured values in the year 2000. Larger values were detected for SEC, alkalinity, total CONCLUSIONS The selected two-month period of observation of physical-chemical characteristics of the Mlini spring is interesting especially because of the possibility of observing the reactions of the spring to the precipitation after prolonged periods of draught. Hydrologicaily interesting is the response of the spring to the first rainfall at the beginning of September, which during two days exceeded 20 mm. The discharge did not change visibly, since the effective infiltration was due to the interception on the vegetation cover, increased evatranspiration and the filling in of the soil moisture deficit practically negligible. Only more intensive rainfall on September 15 resulted in a significant and rapid increase of the discharge, when we also monitored the changes in the composition of water. The discharge increase of the Mlini spring subsequent to the precipitation signifies on the one hand dilution, which was reflected in low concentrations of dissolved substances (SEC, alkalinity, total hardness, cai- 100 ANNALES ■ Ser. hist nat. • 13 • 2003 • 1 lanja K.OCOVSEK el *>.: HYDROCHEMICAL RESEARCH F THE MLiNi SPRINGS. ISTRIA, 9)-t02 cium and magnesium), while on the other hand the precipitation caused intensive washing of the aquifer and also brought into the spring, during the increased discharge and along with enlarged transport power, greater quantities of suspended solids, increased organic pollutants (UV absorption, COD) and particularly bacteriological pollution as well as lager quantities of heavy metals (especially manganese and total chromium) bound to suspended particles. The quantity of mineral oils, which during the initial increased turbidity rose for a brief period, as well as the increase in the quantity of oil and grease during the first increase of the discharge and later in the stabilised hydrologicai conditions parallel to the slowly decreasing discharge, probably reflects a given manner of the transport of substances, which do not mix with water. This phenomenon was detected in karst springs throughout Istria (Dikovic & Stipié, 2000; Dikovic, 2001, 2002). On the basis of the conducted research we may conclude that in order to obtain more accurate picture of the functioning, sampling would be required at intervals of at least 12 hours, which is due to the rapid changes, especially in the initial part of the water waves, whereas the measurements of temperature, SEC and pH by probes (automatic recording of data by means of dataloggers) should be carried out even more frequently. The described detailed manner of spring monitoring significantly supplements the usual karst spring monitoring, which was in the case of Mlini springs conducted at two-month intervals. The temporal planning of more accurate detailed measurements is subject to hydrologicai conditions. The performed measurements have shown that the greatest changes in water composition and quality occur during the increase of the spring's discharge after more extensive precipitation, particularly subsequent to a longer period of dry weather. HIDROKEMIČNE RAZISKAVE IZVIRA MLINI, ISTRA janja KOGOVŠEK inštitut za raziskovanje krasa ZRC SAZU, SI-6230 Postojna, Titov trg 2 E-maii: kogovsek@zrc.-sazu,si Sonja DIKOVIČ Zavod za javno zdravstvo Istarske županije, HR-52100 Pula, V. Nazora 23 Metka PETRIČ inštitut za raziskovanje krasa ZRC SAZU, SI-6230 Postojna, Titov trg 2 josip RUBINIČ Gradevinski fakultet Sveučilišta u Rijeci, HR-51000 Rijeka, V.C. Emina 5 Martin KNEZ Inštitut za raziskovanje krasa ZRC SAZU, SI-6230 Postojna, Titov trg 2 Eiza HRVOjlČ Hrvatske vode, VGO, HR-51000 Rijeka, Dure Šporera 3 Tadej SLABE Inštitut za raziskovanje krasa ZRC SAZU, Si-6230 Postojna, Titov trg 2 POVZETEK V okviru slovensko-hrvaškega medvladnega programa sodelovanja v znanosti in tehnologiji smo jeseni 2001 dva meseca podrobno spremljali kakovost vode na kraškem izviru Mlini, izvir, ki je zajet za vodooskrbo vasi Mlini, leži v srednjem delu površinskega toka Bračane, ki je najpomembnejši desni pritok Mirne. Že od leta /996 je vključen v nacionalni monitoririg kakovosti hrvaških voda, v načrtovani raziskavi pa smo posebno pozornost posvetili detajlnemu spremljanju spreminjanja fizikalno-kemljskih parametrov vode v vodnem valu v ekstremnih hidroloških razmerah. Zajeli smo kratko obdobje nizkega vodostaja, ki so mu sledile kratkotrajne, a intenzivne padavine in oblikovale vodne valove ter daljše obdobje iztekanja in vzpostavljanja stabilnih razmer. Po padavinah povečanje pretoka Mlinov pomeni po eni strani razredčen je, ki se je pokazalo v nižjih koncentracijah raztopljenih snovi (SEP, alkaliteti, celokupni trdoti, kalciju in magneziju). Na drugi strani pa padavine intenzivno spirajo zaledje izvira in ob povečanem pretoku z večjo transportno močjo prenašajo v izvir tudi večje količine 101 ANNALES • Ser. hist, nat. • 13 • 2003 • 1 janja KOGOVŠEK et ¿1.: HYDROCHE'MiCAl RESEARCH Of THE MUNI SPRINGS. (STRIA, 91-102 suspendiranih snovi, povečano organsko onesnaženje (UV absorpcija, KPK) in predvsem bakteriološko onesnaženje ter večje količine težkih kovin (predvsem mangan in celokupni krom), vezanih na suspendirane snovi. Vsebnost mineralnih olj, ki se je kratkotrajno zvišala ob začetni povečani motnosti, ter povečanje vsebnosti skupnih maščob ob prvem naraščanju pretoka ter kasneje v stabilnih hidroloških razmerah ob počasi upadajočem pretoku verjetno odseva način prenosa snovi, ki se z vodo ne mešajo. Ta pojav beležijo v kraških izvirih celotne Istre. Na osnovi opravljenih raziskav lahko zaključimo, da je zaradi hitrih sprememb, predvsem v začetnem delu vod-nih valov, za pridobitev podrobnejše slike dogajanja potrebno vzorčevanje vsaj v intervalu 12 ur, medtem ko je priporočljivo meritve temperature, SEP in pH s sondami (avtomatsko beleženje podatkov z dataloggerji) opravljati pogosteje. Opisani podrobnejši način opazovanja izvirov je pomembna dopolnitev običajnega monitoringa kraškega izvira, ki se v primeru izvira Mlini opravlja v časovnem intervalu dveh mesecev. Časovno načrtovanje podrobnejšega merjenja je vezano na hidrološke razmere. Opravljene meritve so pokazale, da prihaja do največjih sprememb sestave oz. kakovosti vode ob povečanju pretoka izvira po izdatnejših padavinah, predvsem po koncu daljših sušnih obdobij. Ključne besede: kraški izvir Mlini, monitoring, kakovost vode, Istra, Hrvaška, Slovenija REFERENCES APHA (1995): Standard Methods for the Examination of Water and Wastewater. 19"' Edition. Eaton, A. D., L. S. Clesceri & A. E. Creenberg (eds.). American Public Health Association, Washington DC. Dikovic, S. & Ž. Stipič (2000): Program ispitivanja kakvoče voda u Istarskoj županiji u 1999. g. Elaborat arhive Zavoda za javno zdravstvo Istarske županije i Hrvatske vode. Dikovid, S. (2001): Godisnji izveštaj za 2000 g. o pra-cenju kakvoče voda na državnim vodama na području Istarske županije. Elaborat arhive Zavoda za javno zdravstvo Istarske županije i Hrvatske vode. Dikovic, S. (2002): Kakvoca voda na državnim vodama u 2001. g. na području Istarske županije. Elaborat arhive Zavoda za javno zdravstvo istarske županije i Hrvatske vode. Habič, P,, R. Gospodaric, A. Mihevc & F. Šušteršič (1983): Movraška in Smokavska vala ter Jama pod Krogom. Acta carsologica, 11, 77-97. Herak, M. (1991): Dinaridi: mobilistički osvrt na genezu i strukturu. Acta geol. {Prirodoslovna istraživanja. 63), 21(2), 35-117. Pleničar, M., A. Poišak & D. Sikni (1969): Osnovna geološka karta SFRJ, list Trst, 1:100.000. Zvezni geološki zavod, Beograd. Prislov, J. (1998): Vodna bilanca. V: Kolbezen, M (ur.): Površinski vodotoki in vodna bilanca Slovenije. MOP-Hidrometeorološki zavod Republike Slovenije, Ljubljana, str. 41-98. Žugaj, R. (1995): Regionalna hidrološka analiza u krsu Hrvatske. Hrvatsko hidrološko društvo, Zagreb. 102 ANNALES • Ser. hist, nat. • 13 • 2003 • 1 original scientific article . (JDK 556,55.04(234.323.6) received: 2003-07-21 RELATIONS BETWEEN AIR TEMPERATURE, PRECIPITATION AND SURFACE AND VERTICAL WATER TEMPERATURE VARIATIONS iN THE THREE KRIŠKO LAKES (JULIAN ALPS, NW SLOVENIA) IN JULY 2002 Gregor MURI National institute of Biology, SI-1000 Ljubljana, Večna pot 111 Saša ERŽEN Student at the Department of Geography, Faculty of Arts, SI-1000 Ljubljana, Aškerčeva 2 ABSTRACT Dally air temperatures and amount of precipitation were measured at Pogačnikov dom at Kriški podi in July 2002. Surface lake water temperatures in the three Kriško lakes, i.e. Zgornje Kriško lake, Srednje Kriško lake and Spodnje Kriško lake, were also recorded. Vertical lake water temperatures were additionally measured in Srednje Kriško lake and the heat content was calculated. Remarkable fluctuations of surface lake water temperatures were observed. Changes in the mean air temperature and amount of precipitation correlated well with variations of the surface lake water temperature. In the deeper water layers, a correlation between the lake water temperature and changes of meteorological parameters was lower. Lower lake water temperature variations were also observed in this lake section. Nevertheless, the thickness of the epilimnion and the metalimnion varied during the study. The former increased, while the latter shrank, as the days got warmer. The calculation of heat content showed that around 65% of the total heat content in Srednje Kriško lake was stored in the upper two meters of the lake. Key words: air temperature, water temperature, heat content, alpine lakes RELAZIONI TRA TEMPERATURA DELL'ARIA, PRECIPITAZiONi E VARIAZIONI DELLA TEMPERATURA SUPERFÎCIALE E VERTICALE DELL'ACQUA NEI TRE LAGHI Dl KRIŠKO (ALPI GIULIE, SLOVENIA NORD-OCCIDENTALE) NEL LUCIJO 2002 SI NIE Si La temperatura diurna deil'aria e l'ammontare delle precipitazioni sono stati misurati al Rifugio di Pogačnik, local ita Kriški podi, ne I luglio 2002. È stata inoltre registrata la temperatura superficiale dell'acqua nei laghi Zgornje Kriško jezero, Srednje Kriško jezero e Spodnje Kriško jezero. La temperatura verticale dell'acqua è stata misurata solo nel Srednje Kriško jezero. Sono stale osservate notevoli fluttuazioni nella temperatura superficiale dell'acqua del lago. Le variazioni della temperatura média deil'aria e dell'ammontare delle precipitazioni sono state correlate con le variazioni della temperatura dell'acqua superficiale. Negli strati piu profond) la correlazione i/a la temperatura dell'acqua e le variazioni de i parametri meteorologici è ri su Ita ta minore. In questo strato sono state ri le v a te anche le variazioni della temperatura dell'acqua. Gli spessori di epilimnion e metalimnion sono tuttavia cambiati ne! corso dello studio, il primo è aumentato, mentre il secondo si è ridotto con il riscaldarsi dei giorni. Parole chiave: temperatura deil'aria, temperatura dell'acqua, contenuto in calore, laghi 103 ANNALES ■ Ser. hist. nat. ■ 13 • 2003 • 1 CregOf MURI &Saia ER2EN-; RELATIONS BETWEEN AIR TEMPERATURE, PRECIPITATION AND SURFACE AND VERTICAL WATER TEMPERATURE .... 103-1 !0 INTRODUCTION Water temperature is an important parameter in lakes (Wetzel, 1983). It has a strong impact on the biological activity and growth of aquatic organisms, since most aquatic organisms are cold-blooded. Water temperature is also important due to its influence on water chemistry. Some chemical parameters in turn affect biological activity and aquatic life. The rates of chemical reactions, solubility and toxicity of compounds are all temperature dependent (Stumm & Morgan, 1996). An example of the effects of water temperature on water chemistry is its impact on the oxygen concentration. The oxygen concentration in warmer lake water is lower than in cooler lake water. Thus, warmer lake water may be saturated with oxygen but it would still not contain enough oxygen for the survival of aquatic life. Since climatic changes have been observed in the last decades, modelling of water temperature and dissolved oxygen concentration in lakes has received considerable attention over the years in order to asses impact of these two parameters on lakes and their aquatic life in the future (e.g., Antonopoulos & Gianniou, 2003; Ottosson & Abrahamsson, 1998). Seasonal water temperature changes in lakes are mostly correlated with seasonal changes in air temperature. Parameters, such as lake volume, transparency and hydrology all affect water temperature (Wetzel, 1983). Solar radiation is absorbed directly by lake water, while the heat in lake is distributed by mixing of lake water. However, upper water layers are heated more rapidly than the rest of the lake water. As the surface water is warmed, it becomes less dense and the relative thermal resistance of mixing increases. As a consequence, a thermal stratification of lakes is generally observed in the summer. The upper water layers, called the epilimnion, are warm and less dense, while the deeper water layers, called the hypolimnion, remain cold and dense, in the metalimnion, a remarkable drop of water temperature is observed. The epilimnion and the hypolimnion do not mix with each other. Thus, physical, chemical and biological characteristics are usually significantly different in the two layers. In spring and autumn, the water column is mixed completely and spring and autumn turnovers occur. Mountain lakes are specific ecosystems in many aspects. They are remote and not exposed to direct anthropogenic impact. On the other hand, they are small and consequently sensitive ecosystems. Thus, they have been often used as valuable sensors of environmental change (Watline & Rosseland, 2000). Mountain takes are covered with ice for a long period of the year. In the Julian Alps, ice cover periods as short as five and as long as nine months per year were observed (Brancelj, 2002). The duration of ice cover period significantly affects physical and, in turn, chemical and biological conditions in lakes. Also, it has been demonstrated that even small average air temperature changes of 1 to 2*C can lead to evident changes in water chemistry, hydrology and biota (Koinig et a/., 1998; Skjelkvaie & Wright, 1998). Similar conclusions were found in the study on Slovenian mountain lakes (Muri & Brancelj, 2003). The aim of the present work was to study surface and vertical lake water temperature variations in three remote high altitude Slovenian alpine lakes. Three Kriško lakes were selected as study sites, since they are located at different elevation, but close to each other and are similar in size. At the lodge Pogačnikov dom at Kriški podi, the air temperature was measured three times per day, the minimum and maximum temperature was also obtained and precipitation was collected after each rain event in July 2002. Surface water temperatures in Zgornje, and Spodnje Kriško lakes were simultaneously recorded four times per day. In addition, the vertical profile of water temperature in Srednje Kriško lake was measured twice per week and the heat content was calculated. Finally, all parameters were correlated and relation between the air temperature, precipitation amount, lake water temperature and heat content: was studied. Since water temperature is an important physical parameter in lakes, this study contributes to a better understanding of physical and subsequently chemical and biological processes and their changes in mountain lakes. MATERIAL AND METHODS Sampling sites Zgornje, Srednje and Spodnje Kriško lakes are situated in the Julian Alps, NW Slovenia. These mountain lakes are of glacial origin and surrounded by steep slopes. They all lie above the tree level and are relatively small and shallow. Their topographical characteristics are summarized in Table 1, while geographical position is shown in Fig. 1, On average, these lakes are covered with ice for at least seven and even nine months per year (Brancelj, 2002). The mean annual precipitation rate is high, averaging to 3.200 mm per year (Kastelec, 1999). The lakes have no permanent surface inflows. The main bedrock is limestone. Since the lakes are situated in the protected area of Triglav National Park, direct anthropogenic impact on the lakes is scarce and the lakes are still relatively pristine. Tab. 1: Topografske značilnosti merilnih mest (podatki iz Brancelj, 2002). Tab. t: Topographical characteristics of sampling stations (from Brancelj, 2002). j Altitude Sampfmg site fml Surface areajha] Max. depth [m] Zgornje Kriško jezero 2150 0.66 9 Srednje Kriško jezero 1950 0.29 9 Spodnje Kriško jezero j 1880 0.86 9 104 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 Cregor MURI & Sais ER2EN: RELATIONS BETWEEN AIR TEMPERATURE, PRECIPITATION AND SURFACE AND VERTICAL WATf.R TEMPERATURE..., ¡OÎ-tïO Fig. 1: Geographical position of Zgornje, Srednje and Spodnje Kriško lakes. SI. 1: Geografska lega Zgornjega, Srednjega in Spodnjega Kriškega jezera. Measurements of air and water temperature and precipitation The air temperature was measured with a glass thermometer at the lodge Pogačnikov dom at Kriški podi, 2050 m, which is located 100 m (in altitude) above Srednje Kriško Sake. Air temperatures were recorded three times per day, i.e. at 7 AM, 2 PM and 9 PM. A minimum and maximum thermometer was also used to obtain the minimum and maximum air temperatures of the day. All thermometers were placed two meters above the ground in a shaded area protected from strong winds but open to air circulation. Precipitation was also collected at Pogačnikov dom at Kriški podi using a metal canister. Amount of precipitation was measured and emptied manually just after each rain event. Mini thermistors (MINILOG-TR, Vemco) were used to monitor surface lake water temperatures. They were actually positioned approximately 0.25 m below the water surface in order to avoid the highest water temperature fluctuations that occurred on the surface water layer due to changes in intensity of solar radiation. The range of minithermistors was from -4 to 20'C, with a resolution of 0.1"C. The surface water temperature was recorded four times per day. On comparing surface water temperatures in the lakes, the late afternoon values were taken, when the daily highest values were observed. Vertical lake water temperatures were measured using a Pt 1000 probe. Its resolution was 0.1'C in the range from -30 to 100'C. The temperature profile was measured in 1 m intervals above the deepest part of the lake. RESULTS AND DISCUSSION Air temperature and amount of precipitation Air temperatures at the lodge Pogačnikov dom at Kriški podi varied considerably in July 2002 (Fig. 2). 105 ANNAtES • Ser. hist, nat • 13 • 2003 • 1 Gregor MURI &■ Ssia ERŽEN: RELATIONS BETWEEN AIR TEMPERATURE, PR COPITATSON AND SURFACE AND VERTICAL WATER TEMPERATURE .... i 03-110 Maximum air temperatures ranged from 8.0 to 20.0'C, while minimum air temperatures ranged from 3.5 to 11,0'C. The highest minimum and maximum air temperatures were observed at the beginning of the month, on July 11, reaching 11.0 and 20.0"C, respectively. The lowest minimum and maximum air temperatures were also observed on the same day, on July 26. They dropped to 3.5 and 8.0'C, respectively. Variations of the minimum air temperature were not substantial. The minimum air temperature averaged 8.2'C. Higher values Fig. 2: Variations of the daily mean (T mean), minimum (T min) and maximum (T max) air temperatures and amount of precipitation at the iodge Pogačnikov dom at Kriški podi in July 2002. SI. 2: Spreminjanje povprečne dnevne (T mean), minimalne (T min) in maksimalne (T max) temperature zraka in količina padavin pri Pogačnikovem domu na Kriških podih v juliju 2002. Fig. 3: Relations between air temperatures, amount of precipitation and surface water temperatures in Zgornje, Srednje and Spodnje Kriško lakes in july 2002. SI. 3: Odnos med temperaturo zraka, količino padavin in površinsko temperaturo vode v Zgornjem, Srednjem in Spodnjem Kriškem jezeru julija 2002. were observed in the second week of july and in early August. Nevertheless, much lower values were observed around July 26. In contrast, variations of the maximum air temperature were more pronounced (fig. 2). The warmest weather was observed in the second week of july. During this period, the maximum air temperatures ranged around 19.0*C and evidently exceeded the average maximum air temperature, which amounted to 14.7'C. In the rest of the month, the maximum air temperatures were mostly bellow the average value. There were eleven days with rain events (Fig. 2). In total, 164 mm of rain fell The highest amount of precipitation was observed on july 22, when 43 mm of rain was recorded. Substantia! rain events were also observed on July 15 and August 3, with 42 and 25 mm of rain, respectively. During the rest of rain events, !ess than 17 mm of rain was observed. It can be concluded from Fig. 2 that precipitation had a strong impact on air temperatures. During all days, when precipitation events were observed, the mean, minimum and maximum air temperatures decreased remarkably. Surface lake water temperatures Variations of surface lake water temperatures in Zgornje Kriško lake, Srednje Kriško lake and Spodnje Kriško jezero are presented on Fig. 3. Surface water temperatures in Zgornje Kriško lake and Spodnje Kriško lake closely followed each other. Nevertheless, higher values were observed in the latter Sake, Surface water temperatures in Spodnje Kriško lake varied from 12.5 to 17.0*C. In Zgornje Kriško lake, they ranged from 9.6 to 16.8*C. In both lakes, the highest surface water temperatures were observed in the, second week of July. During the rest of the month, they were mostfy lower and averaged to 14.2"C in Spodnje Kriško lake and to 12.5'C in Zgornje Kriško lake. The surface water temperature in Srednje Kriško iake was mostly intermediate between the values observed in the other two lakes (Fig. 3}. Remarkable surface water temperature variations were observed and correlated well with the mean air temperature and intensity, as well as frequency of precipitation events (Fig. 3). Between }u!y 8 and juiy 11, the weather was fine with clear sky. The mean air temperature increased and surface water temperatures in al! lakes also increased. Between july 12 and juiy 19, the weather was mostly cloudy. The mean air temperature dropped considerably, by 5*C. Surface water temperatures also decreased remarkably. Frequent rain events were additionally observed during this period. After rain events, a drop in surface water temperature was even more pronounced. Although the weather was mostly fine between July 20 and july 25, surface water temperature dropped by 2.2 and 1.4'C in Zgornje and 106 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 Gregor MURI & Saw ERŽEN: RELATIONS BETWEEN AIR TEMPERATURE. PRECIPITATION ANO SURE ACE AND VERTICAL WATER TEMPERATURE .... 103 Spodnje Kriško takes, respectively, when the mean air temperature dropped by 5.2°C on a single rainy day (July 22, 43 I of rain). However, on the next day, when the weather improved, almost the same surface water temperatures were observed than before that cold day. A period of very cold and rainy weather followed between July 25 and July 27. The mean air temperature chopped down to 6.2"C and surface water temperatures also decreased steeply. The surface water temperature in Spodnje Kriško lake was 1.8°C lower than the average value, while in Zgornje Kriško lake the difference was even higher and amounted to 2.9"C. In the late July and early August, the mean air temperatures were again higher and so were surface water temperatures. It was also noted that surface water temperatures decreased with increasing altitude of the lakes. In Zgornje Kriško lake they were generally from 1.5 to 2.0'C lower than in Spodnje Kriško lake. Surface water temperatures obtained In Srednje Kriško lake were generally higher than in Zgornje Kriško lake but lower than in Spodnje Kriško lake and were closer to the values obtained in the latter lake since their altitudes are more comparable {Table 1). In Zgornje and Spodnje Kriško lakes, surface water temperatures were recorded four times'per day. Thus, surface water temperature variations in-different--periods" of the day were also observed. Surface water temperatures in the two lakes were normally the highest in the late afternoon but varied as much as 4"C during sunny days with clear sky. In contrast, they varied for less than 0.5'C during cold and cloudy days. Most of the solar radiation that, affects the lake water temperature is absorbed in the surface water layers (Wetzel, 1983). Remarkable variations of surface water temperatures during the day are thus expected. Vertical lake water temperatures and heat content Vertical water temperature profiles were measured only In Srednje Kriško lake. Water temperature decreased with depth (Fig. 4). It was quite uniform in the upper water layers (the epilimnion). The highest values were observed at the water surface and ranged from 13.4 to 16.0'C. Between depths of approximately two and five meters, water temperature dropped remarkably, by about 5'C (the metalimnion). In the deeper water layers (the hypolimnion), only slight variations of water temperature were observed. It varied from S.7 to 7.7'C. _O_0S.07.2002 -a- 11.07.2092 22,07.2002 _A_02.0S.2002 Fig. 4: Vertical profiles of water temperatures in Srednje Kriško lake in July 2002. SI. 4: Globinski profili temperature vode v Srednjem Kriškem jezeru julija 2002. 107 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 Gregor MURI & Saša ERŽEN: RELATIONS BETWEEN AIR TEMPERATURE, PRECIPITATION AND SURFACE ANO VERTICAL WATER TEMPERATURE .... 103-110 Vertical water temperatures in Srednje Krisko lake were also compared with changes in the mean air temperature and amount of precipitation. A higher correlation between meteorological parameters and water temperatures was observed in the epiiimnion than in the hypolimnion. Vertical water temperature profiles (Fig, 4) showed that deeper water layers were much less susceptible to outside conditions, such as precipitation events and intensity of solar radiation than surface waters. Lower variations of the water temperature were also observed in this lake section. Deeper water layers have a certain heat capacity and cannot be so quickly warmed up or cooled down than the upper water layers (Wetzel, 1983). Additionally, epiiimnion and hypolimnion waters do not mix dLie to differences in water density, thus further retarding the heat transfer through the water column. The thickness of the epiiimnion, the metalimnion and the hypolimnion also changed with time (Fig. 4). On July 8, the epiiimnion was only two meters thick, whereas one month later, on August 2, it amounted to three meters. The thickness of the metalimnion and the temperature drop in it also changed. The metalimnion was thick as much as four meters on July 8, but shrank to two meters on August 2. Also, the water temperature dropped by nearly 7'C on the former day but only by 4.5°C on the later day. The thickness of the hypolimnion remained nearly the same throughout the time of experiment, amounting to around two meters and starting at a depth of approximately six meters. These water layers are thus relatively independent from outside conditions. The vertical distribution of heat content was also calculated for Srednje Kri§ko lake (Fig. 5). Meter by meter distribution of the heat content was initially calculated, according to the formula m Cp AT. m is the mass of the layer (calculated as p S h; p is the density of water (1 kg dm'3), S the area of the layer and h the height (1m). Cp is specific heat of water (4.2 j g'1 K"'), while AT delineates the temperature difference, of the layer relative to O'C. The total heat content was finally calculated as a sum of the heat stored in all layers of the lake. If. was normalized to the surface area of the lake. The lake was subsequently divided into three different sections. The upper section extended from 0 to 2 meters, the second one from 2 to 5 meters, and the bottom one from 5 to 8 meters. These lake sections roughly represented epilimnetic, metalimnetic and hypolimnetic waters, respectively. During July 2002, the total heat content of the lake averaged to 138 Mj m"5. This value is comparable to the values that were determined In other lakes of similar size and depth (e.g. Ambrosetti & 8ar-banti, 2001). The average contribution of the epilimnetic waters was 90 Mj while metalimnetic and hypolimnetic waters contributed 43 and 6 Mj m'2 to the total heat content, respectively (Fig. 5). The calculation hence showed that the upper section of the lake (0-2 m) comprised from 62 to 68% of the total heat content. Most of the heat in the Sake was thus stored in the epiiimnion. In addition, it was found that the relative contribution of this layer to the total heat content decreased during the study, since the lake warmed up (Figs. 4 and 5). The 2-5 m section contributed from 29 to 33% to the total heat content. Its contribLition in contrast increased slightly during the study. The bottom section (5-8 m) contributed only 4% to the total heat content and its contribution remained very uniform during the study. Only a minor part of the heat was thus stored in the hypolimnion. ÍM1-IJO 12ÍI-tiHJ SO » t 5.« to Ql-5 m Q C.-i M HI H.r»,3!«E ÍM17.2WJ ^.rií.ífflí! 2íi,í3~.2(lfj;: ^.ÍRJÍWJ Fig. 5: Vertical distribution of beat content in Srednje Kriško lake in July 2002. SI. 5; Vertikalna porazdelitev toplote v Srednjem Kriškem jezeru julija 2002. Effects of lake water temperature on lake condition The lakes, selected in this study, are relatively small lake systems. Thus, a fast response between the air temperatures, amount of precipitation and surface water temperature was observed. Surface water temperatures in the lakes changed daily. In contrast, a longer time period (of weeks) was needed for an evident change of water temperature in the deeper water layers. Water temperature changes are important, since they affect chemical and biological processes in lakes and have a significant impact on the overall condition in them. Aquatic species have preferred temperature ranges for living, but in general biological activity and growth rate of aquatic organisms are higher when water temperature increases (Lampert, 1984). During the study carried out in three other Slovenian mountain lakes (i.e. Krnsko jezero, Jezero v Ledvicah and jezero na Planini pri jezeru), primary producers were less abundant in the years with long duration of snow and ice cover and consequently cold lake water temperatures. The overall conditions in these lakes have improved in comparison with those in the years with warmer lake water (Muri & Brancelj, 2003). 108 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 Gregor MURI & Saša ERŽEN: RELATIONS BETWEEN AIR TEMPERATURE, PRECIPITATION AND SURFACE AND VERTICAL WATER TEMPERATURE .... 103-U0 CONCLUSIONS Changes of the daily air temperature and amount of precipitation were measured at the lodge Pogačnikov dom at Kriški podi in July 2002. These changes were compared with the surface water temperature variations in Zgornje, Srednje and Spodnje Kriško lakes. Significant correlation was found between the three measured parameters. Vertical water temperatures were additionally measured in Srednje Kriško lake and the heat content was calculated. It was established that water temperature variations in the deeper layers of the water column were less correlated with the changes of meteorological parameters. A longer time was also needed to warm up its bottom water layers. The calculation of heat content showed that approximately two thirds of the total heat content is stored in the upper, epilimnetic waters. The meta limnetic waters comprised around one third of the total heat content, while the heat stored in the hypolim-netic waters was of minor importance. Water temperature changes in lakes are important, since they affect chemical and biological processes in them, and can thus change their overall conditions. ACKNOWLEDGEMENTS The minithermistor data were obtained within the framework of the EU project EMERGE. A. Brancelj is acknowledged for kindly providing these data. We are also grateful to M. Šiško for the balhymetnc data of Srednje Kriško lake. The manuscript gained from the helpful comments of j. Faganeli and one anonymous reviewer. ODNOS MED TEMPERATURO ZRAKA, PADAVINAM! TER NIHANJEM POVRŠINSKE IN GLOBINSKE TEMPERATURE VODE V TREH KRIŠKIH JEZERIH (JULIJSKE ALPE, SZ SLOVENIJA) V JULIJU 2002 Gregor MURI Nacionalni inštitut za biologijo, Si-1000 Ljubljana, Večna pot 111 Saša ERŽEN Študentka na Oddelku za geografijo, Filozofska fakulteta, St-1000 Ljubljana, Aškerčeva 2 POVZETEK Pri Pogačnikovem domu na Kriških podih smo julija 2002 merili dnevno temperaturo zraka in količino padavin. Poleg tega smo odčitavali površinsko temperaturo vode v Zgornjem, Srednjem in Spodnjem Kriškem jezeru, medtem ko smo v Srednjem Kriškem jezeru merili temperaturo vode tudi po globini vodnega stolpca, iz česar smo nato izračunali porazdelitev toplote v tem jezeru. Opazili smo precejšna nihanja površinske temperature vode. V Zgornjem Kriškem jezeru je površinska temperatura vode nihala za 7.2'C, v Spodnjem Kriškem jezeru pa za 4.5'C. Spremembe povprečne dnevne temperature zraka in količine padavin so bile medsebojno povezane s spremembami površinske temperature vode. Korelacija med temperaturo vode v globljih plasteh vodnega stolpca in meteorološkimi parametri je bila slabša. Tudi nihanja temperature vode so bila v globljih plasteh vodnega stolpca manjša, saj je v hipollmnlju Srednjega Kriškega jezera temperatura nihala le za 2'C. Spreminjali pa sta se debelini epilimnlja in metallmnija v času študije v tem jezeru. Debelina epilimntja je narasla od dva na tri metre, medtem ko se je debelina metallmnija skrčila iz štirih na dva metra, ko so dnevi postajali toplejši. Debelina hipolimnija je bila v času študije enaka in je znašala okrog dva metra. Izračun porazdelitve toplote v Srednjem Kriškem jezeru je pokazal, da je vrhnja plast vode (0-2 m) vsebovala približno 65% celotne toplote v jezeru. Območje 2-5 m je vsebovalo okrog 31 %, predel 5-8 m pa te še 4% celotne toplote v jezeru. Ključne besede: temperatura zraka, temperatura vode, toplota, alpska jezera 109 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 CfegorMURI & 5a5a ERZEN; RELATIONS BETWEEN AIR TEMPERATURE. PKtOPITATION ANO SURFACE AND VERTICAL WATER TEMPt.RA'iURE .... lOi-UJ REFERENCES Ambrosetti, W & L. Barbanti (2001): Temperature, heat content, mixing and stability in lake Oria: a piuriannual investigation, j. Limnol., 60, 60-68. Antonopouios, V. 2. & S. K. Gianniou (2003): Simulation of water temperature and dissolved oxygen distribution in Lake Vegorltis, Greece. Ecol. Model., 160, 39-53. Brancelj, A. (ed.) (2002): High-mountain lakes in the eastern part of the julian Alps. ZRC Publishing, Ljubljana. Kastelec, D. (1999); Use of universal krlging for objective spatial interpolation of average yearly precipitation in Slovenia. Res. Rep. Biotech. Fac. Univ. Ljubfj. Agric. Issue 73, 301-314 (in Slovenian, with English abstract). Koinig, K, A., R. Schmidt, S. Sommaruga-Wograth, R. Tessadri & R. Psenner (1998): Climate change as the primary cause for pH shifts in a high alpine lake. Wat. Air Soil Pollut., 104, 167-180. Lampert, W. (1984): The measurement of respiration, in: Downing, j. A. & Rigler, F. H. (ed.): A manual on methods for the assesssment of secondary productivity in fresh waters. Oxford, Blackwell, 413-468. Muri, C. & A. Brancelj (2003): Seasonal water chemistry variations in three Slovenian mountain lakes. Acta Chlm. Slov., 50, 137-147. Ottosson, F. & O. Abrahamsson (1998): Presentation and analysis of a model simulating epilimnetic and hy~ poiimnetic temperatures in lakes. Ecol. Model., 110, 233-253. Skjelkvale, B. L. & R. F. Wright (1998): Mountain lakes; sensitivity to acid deposition and global climate change. Ambio, 27, 280-286. Sfumm, W. & j. J. Morgan (1996): Aquatic chemistry, chemical equilibria and rates In natural waters, Wiley Sntersclence Publication, New York. Wathne, 8. M., B. O. Rosseiand, (Eds.), (2000): MOLAR Final Report 4/1999. Measuring and modelling the dynamic response of remote mountain lake ecosystems to environmental change: A programme of Mountain Lake Research - MOLAR. NIVA, Oslo. Wetzel, R. G. (1983): Limnology. Saunders College Publishing, Philadelphia. 110 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 pregledni članek UDK 556.36(497.4 Kras) prejeto: 2003-04-11 KRAŠKI IZVIRI BISTRICE (JZ SLOVENIJA) Gregor KOVAČIČ Fakulteta za humanistične študije Koper, Univerza na Primorskem, SI-6000 Koper,'Glagol jaška 8 E~maii: gregor.kovacic@fhs-kp.si IZVLEČEK Stalni in občasni kraški izviri v okolici Ilirske Bistrice (JZ Slovenija} z ocenjenim skupnim srednjim letnim pretokom 1.850 m3/s pritekajo na površje na stiku krednih apnencev in eocenskega fliša na zahodnem robu dobro namočene Snežniške planote, ki tektonsko pripada Snežniški narivni grudi. Hidrografsko zaledje izvirov je neposeljena Snežniška planota, kar je za varovanje kakovosti pitne vode v izvirih ugodno. Kljub temu v zaledju najdemo manjše število bolj ali manj resnih potencialnih in dejanskih onesnaževalcev. Mikrobiološka in fizikalno kemijska kakovost vode v izviru Bistrica, ki je tudi zajet za vodooskrbo, je dobra, toda vodovarstveni pasovi niso opredeljeni in varstvenega režima tu ne uresničujejo. Ključne besede: kraški izvir Bistrica, kraška hidrologija, Snežniška planota, JZ Slovenija SORGENTI CARSiCHE Dl BISTRICA (SLOVENIA SUD-OCCIDENTALE) SINTbSl Le sorgenti carsiche permanent! ed intermittenti nei pressi di Ilirska Bistrica (Slovenia sud-occidentale), con un flusso totale medio annuo di 1.850 m3/s, sgorgano in superficie al contatto tra calcari gessosi e flysch eocenico, sul ciglione occidentale della ben irrigata pianura di Snežnik che, tettonicamente parlando, appartlene alia zolla naturale di Snežnik. II refroterra idrografico delle sorgenti e costituito dalla non popolata pianura di Snežnik, il che e un vantaggio per la hitela della qualith dell'acqua potabile proveniente dalle sorgenti. Nonostante cib nel retroterra troviamo un discreto numero di inquinatori potenziali o effettivi. La qualita microbiologica e fisico-chimica dell'acqua alia sorgente di Bistrica, alia quale si attinge per I'approvvigionamento idrico, e buona, benche le fasce di tutela dei corsi d'acqua non slano state definite e il regime di protez ione non sia s ta to messo in atto. Parole chiave: sorgente cars i ca Bistrica, idroiogia carsica, pianura di Snežnik, Slovenia sud-occidentale 111 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 Gregor KOVAČI C: KRAŠKI IZVIRI BISTRO {¡Z SLOVENIJA), 1 H-520 UVOD Kraški izvir Bistrica in izviri v njegovi okolici do sedaj niso vzbudili velikega zanimanja pri raziskovalcih, čeprav je že leta 1938 o kakovosti in pretokih zajetja Bistrica ter legi posameznih izvirov v njegovi okolici poročal Boegan. Tako v literaturi najdemo le tu in tam nekaj podatkov o fizikalno-kemični kakovosti in izdatnosti izvira Bistrica (Brečko-Grubar & Plut, 2001), nekoliko več pa je zapisanega o Bistrici kot o najmočnejšem kraškem pritoku svetovno znane ponikalnice Reke (Rojšek, 1987, 1996). Bistrica je kljub majhni izdatnosti eden pomembnejših kraških izvirov v jugozahodni Sloveniji (Brumen et al., 1991), saj s pitno vodo oskrbuje večji del občine Ilirska Bistrica, nekaj naselij v občini Hrpelje-Kozina ter del Republike Hrvaške. V zvezi s pripravo strokovnih podlag za sprejetje odloka o zavarovanju pitne vode iz omenjenega izvira je bilo po naročilu Občine Ilirska Bistrica in upravljavca zajetja, Komunalnega podjetja ilirska Bistrica, opravljenih več hidrogeoloških raziskav zaledja ijuren & Krivic, 1989; Petauer et al., 2002!, žal brez sledilnih poskusov in vrtin. Zbranih je bilo tudi nekaj podatkov o izdatnosti ter fizikalno-kemičnih značilnostih vode iz zajetja. Celovitega opisa geografskega položaja izvirov v neposredni bližini mesta Ilirska Bistrica v povezavi s hidrološkimi razmerami v zaledju še nimamo, zato je besedilo pomemben prispevek k boljšemu poznavanju hidrološke situacije na tem območju jugozahodne Slovenije. GEOGRAFSKI POLOŽAJ STALNIH IN OBČASNIH KRAŠKIH IZVIROV Stalne in občasne kraške izvire pri Ilirski Bistrici lahko obravnavamo kot enoten hidrološki sistem. Izviri so razporejeni ob zahodnem vznožju Snežniške planote 5/. 1: Geografski položaj obravnavanih izvirov. Legenda; 1. Stalni izvir, 2. Občasni izvir, 3. Zajetje za vodovod, 4. Kredni apnenci, 5. Eocenski fliš, 6. Rečni sediment i, 7. Vodomerna postaja Ilirska Bistrica, 8. Kamnolom. Fig. 1; Geographic position of the karst springs. Legend: 1. Permanent spring, 2. Periodical spring, 3. Water supply capture, 4. Cretaceous limestones, 5. Eocene flysch, 6. Fluvial sediments, 7. Ilirska Bistrica gauging station, 8. Quarry. 112 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 Gregor KOVAČIČ: KRAŠKI ¡ZVIRi BISTRICE (IZ SLOVENI|A), 1 1 M 20 oziroma Snežniškega pogorja, kjer kraški svet, zgrajen iz apnencev, dolomitov, apnenčastih in dolomitnih breč pretežno kredne starosti, v stopnji prehaja v flišne se-dimente brkinske sinklinale. Vode na dan prisili v podlagi slabo prepusten fliš, prek katerega so narinjene karbonatne kamnine Snežniške narivne grude. Kraški rob na tem delu ni tako izrazit, kot ga denimo lahko opazujemo v zatrepni dolini kraškega izvira Podstenjšek severozahodno od tod ali pa vzdolž toka Reke jugovzhodno od obravnavanih izvirov. Kljub temu se apniški svet v Suški rebri na zelo kratki razdalji spusti več kot 100 m do flišne podlage ilirskobistriške kotline. Lokalno erozijsko bazo izvirov tvori Reka, ki v okolici Ilirske Bistrice vijuga po svoji poplavni ravnici. Reka je svoje osamljeno porečje razvila na neprepustnih flišnih kamninah, ki jih z vseh strani omejujejo dobro prepustne kraške kamnine z bolj ali manj razvitimi kraškimi vo~ donosniki. Preučevani izviri, ki so razporejeni na razdalji približno enega kilometra, se v Reko stekajo v dveh pritokih (5l. 1). Pritok Bistrica, ki je dolg vsega skupaj 1,65 km (Rojšek, 1996), se napaja z izviri Bistrice ter izviroma Sušeč in Kovačevec. Relativna višinska razlika med izvirom in izlivom je približno 30 m. Bistrica je najmočnejši kraški pritok Reke, z zelo pomembnim učinkom kraške retinence v sušnih obdobjih, ko ima ta malo vode. Pritok Pila oziroma Kozlek se napaja iz istoimenskih kraških izvirov. Bistrica izvira pod prepadnimi stenami na stiku apnenca in fiiša v značilni zatrepni dolini neposredno za zadnjimi hišami najstarejšega predela Ilirske Bistrice, imenovanega Sibirija, na nadmorski višini 425 m (SI. 2). Zajetje za pitno vodo, ki mu pravijo Pod steno in je 90 m umetno izkopani drenažni rov, leži nekaj metrov niže. Za omenjeno zajetje oziroma vodni vir se poleg izvir Bistrice uporablja še ime Pod Gradino, Sibirija ali pa vodni vir Ilirska Bistrica. Izvir je pozidan, tako da naravnega iztoka vode ni (SI. 3). Nad zidanimi rezervoarji najdemo dva hudourniška jarka, ki segata do nadmorske višine 475 m in se zaključujeta z manjšo steno. Pobočja zatrepne doline so prekrita z gruščem. Kaže, da voda po hudournikih v izvir priteče le ob izjemnih padavinah. Drenažni rov sedanjega zajetja, ki leži na nadmorski višini 420 m, usmerja podzemni tok vode iz ožje okolice in širšega zaledja naravnost v zajetje pitne vode. V zatrepni dolini Bistrice izvirata še dva občasna kraška izvira, ki pršvreta na dan ob visokih vodah. Kukčevka je manjši slap, ki izvira iz skalne razpoke in se že po nekaj metrih toka združi z Bistrico. Kukčevka leži znotraj I. vodo varstvenega območja zajetja, ki je ograjeno. Z desne strani iz razpoke v steni privre na dan Prhovčevka, ki se v skočnikih med poslopji po nekaj 10 m izliva v Bistrico. Struga Bistrice je utrjena s kamnitimi brežinami od zajetja pa skoraj do izliva v Reko. Strnjena pozidava vzdolž struge v ozki zatrepni dolini je vezana na nekdanjo izrabo pogonske moči vodnega toka za delovanje žag in mlinov (SI. Dejavnost te vrste j« povsem zamrla, nekdanji mlini in žage pa so v razvalinah. Sušeč je levi pritok Bistrice, ki.izvira iz strme apniške stene na koncu manjše zatrepne doline. Zatrepna dolina Sušca in Bistrice sta med seboj , ločena z nizkim in kratkim, toda dokaj izrazitim slemenom. Sušeč je najsiikovitejši izmed obravnavanih izvirov. Voda izvira iz razpok v steni in pada v obliki dveh manjših slapov in skočnikov (SI. 5). Sušeč je občasen izvir, višina izviranja vode pa je v precejšnji meri odvisna od trenutne hidrološke situacije. V običajnih razmerah voda privre na dan iz razpok v skalovju na višini približno 425 m, ob visokih vodah pa slap izvira iz apnenčastega grušča ob vznožju manjših podornih sten v strmem pobočju Suške rebri tudi od 10 do 15 m više. Hudourniške grape je moč opazovati vse do skrajnega vrhnjega roba zatrepne doline nekaj 10 metrov više, kjer so opazni tudi manjši podori. Sušeč se hitro odzove na padavine v zaledju, kar se kaže v hitrem naraščanju in upadanju pretoka. S/. 2: Zatrepna dolina kraškega izvira Bistrice. (Foto: C. Kovačič) Fig, 2: Pocket valley of the Bistrica karst spring. (Photo: C. Kovačič) 113 ANNALES • Ser. hist. nat. • 13 ■ 2003 • 1 Gregor KOVAČ tČ: KRAŠKI !ZVIR[ BISTRICE (IZ SI. OVEN M A), 1 11-120 - ■ ■ '■■'. . ^ -V": ' '■■'/.%V' - ' ' . - -V; - t- Vr - - "'i ■■ ■ ; . V '. :'. -V. ■ ■ ■ ■■ ■',.„>, ■■:■■-.■ "v". :■■■■■?■ ■ --. ; ■ I ■■■ .i-.". ■. /■.; . Vr : • i\v ■\.?i - ■ .v.;,. ■. i . ■■ ■ " . •• •• ^wi^mriiinm •• . '.a. . . f . ■. ■ ■■ ■'■•■ . ■' ■ ■ ■ mM •• v ■ ■ -w? v^ - 4 ■;. ¿fl«! Pila je manjši kraški izvir, ki prihaja na dan ob stiku apnenca s flišem ob visokih vodah na nadmorski višini približno 470 m. Število posameznih izvirov na lokaciji in njihova višina sta močno odvisna od trenutne hidrološke situacije, saj se ob visokih vodah število izvirkov na lokaciji poveča, ob nizkih vodah pa voda izvira precej niže. Ob padavinskih viških voda išče pot skozi območja slabše prepustnosti v apnenčastem grušču, ki prekriva pobočje pod manjšimi stenami kraškega roba. Posledica je zelo povečan pretok v potoku, ki je običajno zelo majhen, vendar stalen. HIDROLOŠKE ZNAČILNOSTI IZVIROV IN NJIHOVO ZA L E D J E Si. 3: Izvir Bistrice je za vodooskrbo zajet že na začetku. (Foto: G. Kovačič) Fig. 3: The Bistrica karst spring is tapped for water supply at its very source. (Photo; G. Kovačič) Kovačevec je manjši občasni izvir, ki prihaja na dan iz razpok v steni na kraju neizrazite in kratke zatrepne doline. Ob srednjih in nizkih vodah izvira voda izpod stene na nadmorski višini 430 m. Ob dvigu nivoja podzemne vode voda izvira 15 m više neposredno iz grušča, ki se napaja skozi razpoke v apnenčasti podlagi. Ob visokih vodah se v neposredni bližini aktivira manjši slap, ki priteče iz korozijsko razširjene razpoke v apnenčasti steni. Kozlek izvira na območju opuščenega kamnoloma in je eden izmed stalnih izvirov na območju. Voda izvira na nadmorski višini 440 m iz podornega kamenja, ki leži pod manjšo steno, izvir hitro reagira na padavine s povečanim pretokom, potem pa sledi dolgo obdobje izredno nizkih pretokov. Ob izviru se je med deli v kamnolomu odprla krajša jama, ki jo v svojem delu opisuje Boegan (1938). S/. 4: Stari del Ilirske Bistrice, imenovan Sibirija. (Foto: C. Kovačič) Fig. 4: The old part of the town of Ilirska Bistrica named Sibirija. (Photo: G. Kovačič) Hidrografsko zaledje izvirov je razmeroma dobro omejeno samo s flišnim obrobjem ob Reki, ki teče vzporedno z bolj ali manj izrazitim kraškim robom zahodnega dela Snežniške planote v značilni dinarski smeri. Strma pobočja pod robom prekrivajo apneni grušči, sestavljeni iz skalnih odkruškov različnih velikosti. Ti značilno prekrivajo tudi rebri krajnih koncev zatrepnih dolin kraških izvirov. Fiišne kamnine v tainini snežniške narivne grude (Placer, 1981) so za podzemne kraške vode nekakšna hidrološka pregrada, kar usmerja podzemni tok kraške vode z zahodnega roba Snežniške planote v porečje Pivke, V njenem zgornjem toku prihaja do bifurkacije med jadranskim in črnomorskim po-vodjem (Habič, 1984). Kaže, da je flišna pregrada prebita samo na območju obravnavanih izvirov in pri kraškem izviru Podstenjšek. Obseg kraškega zaledja izvirov v notranjosti Snežniške planote je po do sedaj razpoložljivih podatkih praktično nemogoče opredeliti, saj je hidrografska meja med napajalnim zaledjem Bistrice, Pivke, Cerkniškega jezera in Riječine (Hrvaška) zelo nejasna in verjetno prostorsko in časovno močno spremenljiva glede na padavinske in hidrološke razmere na območju. Sledilnih poskusov na območju niso napravili. Ocena, da hidrografsko zaledje kraškega izvira Bistrica obsega površino približno 90 km2 (Juren & Krivic, 1989; Petauer ef al., 2002), je nekoliko pretirana. Kljub temu je s stališča varovanja pitne vode smiselna, saj so jo zaradi slabšega poznavanja terena in da bi se izognili morebitnim nepremišljenim posegom v naravo, pomaknili do roba izrazitega dinarskega preloma, kjer so opazne vidne geološke spremembe terena, Z izjemo Pile in Kozleka vodomerna postaja Ilirska Bistrica (Bistrica) zajema vode vseh obravnavanih kraških izvirov. Postaja leži na nadmorski višini 393 m v bližini izliva Bistrice v Reko. Po hidroloških podatkih za obdobje 1958 dol 998 (v letih od 1974 do 1989 meritev niso opravljali) se srednji letni pretoki sučejo med 0,86 in 2,56 mVs (Qs= 1,6 m7s) (HMZ RS, 1999), pri tem pa je treba v skupni bilanci iztoka vode upoštevati odvzem vode za potrebe vodovoda, ki je neodvisno od letnega časa približno 0,100 mVs. Minimalni pretoki se gibljejo 114 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 Cregoi KOVAOC KRAŠKI IZVIR! BISTRICE {JZ SLOVENIJA), l ] 1-1 20 med 0,044 in 0,560 m3/s in so dolgotrajnejši. Maksimalni pretoki med 3,39 in 36,50 m /s so kratkotrajni, ekstremni viški pa se pojavljajo hkrati z izjemnimi padavinskimi dogodki v zaledju. Pretok Bistrice skoraj polovico dni v letu ni večji od 1 m3/s. Indeks prepiav-ijenosti znaša 1 : 36 : 830, kar kaže na sistem dobro razvite kraške poroznosti z zelo hitrim tokom in istočasno na omejeno sposobnost skladiščenja v vodonos-niku. Če upoštevamo odvzem, se vrednost indeksa preplavljenosti zmanjša na 1 : 12 : 254. Zaradi slabše prepustnosti stalnih in niže ležečih izvirov se ob močnejših padavinah nivo podzemne vode dvigne. Potek praznjenja vodonosnika zaznamuje hitri upad povečanih pretokov v više ležečih izvirih. Do znatnejšega upada pretoka, ki je posledica upada gladine podzemne vode v zaledju, prihaja najprej pri Pili, sledijo Kozlek in drugi izviri do kraškega izvira Bistrica. Prepustnost slednjega je precej omejena, kar se ob močnejših padavinah kaže v povečanem pretoku v občasnih izvirih. Slabša prepustnost stalnih izvirov je verjetno tudi posledica dejstva, da tam ni izvirskih jam, ki jih iahko opazujemo v kraških izvirih drugod po Sloveniji in svetu. Možno je, da sicer obstajajo manjše izvirske jame, ki pa so bodisi zapolnjene in tako slabše prevodne bodisi zasute s pobočnim gruščem in jih zato ni opaziti. Možno je tudi, da se preprosto končajo z zapletenim sistemom številnih razpok v skalovju, ki so pogoste na narivnem robu. Vloge tektonske pretrtosti narivnega roba na razporeditev izvirov in na njihove hidrološke posebnosti ne gre zanemarjati, čeprav ta še ni pojasnjena, V hidroloških podatkih za vodomerno postajo Ilirska Bistrica nista zajeta izvira Pila in Kozlek. Podatkov o njihovih pretokih nimamo, vendar skupni srednji letni pretok v seštevku verjetno ne presega 0,150 mVs. Minimalna izdatnost kraškega izvira Bistrica je ocenjena na 0,200 m3/s (Kovačič, 2001 a), kar je približno toliko, kot je izmerjeni srednji minimalni pretok Bistrice na vodomerni postaji Ilirska Bistrica. V sušnih mesecih se Bistrica polni pretežno z vodo iz omenjenega izvira. Prva merjenja pretokov kraškega izvira Bistrica so bila opravljena že ob koncu devetnajstega in v začetku prejšnjega stoletja, rezultate o meritvah pa je v svojem delu zapisal Boegan (1938), V obdobju med 1870 in 1928 je bila zabeležena minimalna izdatnost 0,116 m3/s (1. 9. 1911) ter maksimalna izdatnost 3,18 m3/s (27. 3. 1928). V istem delu so zabeleženi rezultati nekaj meritev pretoka na občasnih kraških izvirih Sušeč in Kovačevec v letu 1928. Pretoki Sušca se gibljejo med 0,160 in 0,820 m3/s, pretoki Kovačevca pa med 0,001 in 0,472 m3/s, avtor pa navaja, da omenjena izvira v sušnih poletnih mesecih popolnoma presahneta. Pomanjkljivost podatkov o pretokih je, da niso dovolj reprezentativni, saj merjenj niso opravljali sistematično v vseh letnih časih. Tako denimo nimamo podatkov o pretokih v zimskih mesecih in še posebej v mesecu novembru, ko so izviri najbolj izdatni. Kljub temu dajejo pomembno informacijo, saj novejših podatkov nimamo. Časovna razporeditev srednjih mesečnih pretokov Bistrice pokaže dva letna viška. Prvi in izrazitejši višek se časovno ujema z veliko količino padavin v mesecu novembru, ki je med vsemi meseci v letu najbolj namočen. Visoki pretoki se ohranjajo do meseca februarja, ko nastopi manj izraziti nižek. Sekundarni višek pretokov se pojavlja v mesecu aprilu. Primarni nižek se pojavlja v poletnih mesecih. Nadpovprečni srednji mesečni pretoki so značilni za hladno polovico leta, z izjemo meseca februarja, ko so pretoki nekoliko nižji od letnega povprečja. Sekundarni aprilski višek je posledica taljenja snega v pomladanskih mesecih, saj zimski in spomladanski meseci odražajo podpovprečne vrednosti količine padavin. Vendar pa učinek taljenja snega v zaledju ni posebej izrazit, saj srednji aprilski pretok le malo presega srednji letni povprečni pretok in je tudi manjši od pretokov v mesecih od oktobra do januarja. Napajalno zaledje izvirov potemtakem obsega tudi območja, ki jih pozimi prekriva sneg, vendar gre tu za predele s tanjšo in manj časa trajajočo snežno odejo. Ocenjeni skupni srednji letni odtok iz obravnavanih izvirov znaša približno 1.850 irtVs. Ob predpostavki, da so spremembe v količini uskladiščenja vode v dolgoletnem obdobju enake 0, lahko na podlagi podatkov o količini padavin v zaledju in podatku o evapotranspiraciji ocenimo velikost zaledja izvirov. Seveda gre zgolj za površno oceno, saj na napajanje kraškega vodonosnika vplivajo še številni drugi dejavniki, kot sta denimo taljenje snega in prestrezanje padavin na rastlinskem pokrovu (Petrič, 2002). Poleg tega gre za oceno velikosti zaledja, ne pa tudi obsega in njegovih mej. Skupna letna količina padavin na padavinski postaji Ilirska Bistrica, ki leži dober kilometer severneje od izvirov, znaša 1446,8 mm (Zupančič, 1995), korigirana vrednost pa 1569 mm (Kolbezen & Pristov, 1998). Hidrografsko zaledje izvirov S/. 5: Kraški izvir Sušec ob visoki vodi novembra 2002. (Foto: C. Kovačič) Fig. 5: High discbarge of the Sušeč spring in November 2002. (Photo: G. Kovačič) 115 ANNALES ■ Ser. hist. nat. • 13 • 2003 • 1 Gregor KOV AGIO KRAŠKI IZVIRI BISTRICE (JZ SLOVENIJA), 1 1 1-120 Qs (m3/s) 4 T Padavine (1961-90) Pretoki (1958-98) SI. 6: Povprečni mesečni pretoki Bistrice v obdobju 1958-98 na vodomerni postaji Ilirska Bistrica in povprečne mesečne padavine v obdobju 1961-90 na padavinski postaji Ilirska Bistrica (HMZ RS, 1999; Zupančič, 1995). Fig. 6: The Bistrica monthly mean discharges (period 1958-98) at the Ilirska Bistrica gauging station and monthly mean precipitation (period 1961-90) at the Ilirska Bistrica precipitation station (HMZ RS, 1999; Zupančič, 1995). je dobro namočeno. Proti notranjosti Snežniške planote padavine zaradi orografske pregrade naraščajo ter na zahodnem robu Snežniške planote in v povirnem delu Reke presežejo 1800 mm. Podatki za Mašun (2041 mm/letno) in južneje ležeče Gomance (2738 mm/letno) kažejo, da se količina padavin proti osredju planote še veča in znaša približno 2500 mm, na najvišjih predelih pa celo 3000 mm. Snežniška planota je v povprečju 100 dni na leto pokrita s snežno odejo, njena letna maksimalna višina pa se giblje med 20-200 cm (Koibezen & Pristov, 1998; Zupančič, 1998; Kovačič, 2001). Višja nadmorska lega zaledja in posledično nižje temperature povzročajo slabše izhlapevanje, prepustna, karbonatna kamninska podlaga pa omogoča hitro prenlkanje vode v globino, kar tudi zmanjšuje možnost izhlapevanja, povečuje pa podzemni vodni odtok z območja. Če vzamemo 1800 mm padavin kot povprečno množino padavin v zaledju in upoštevamo 620 mm letnega izhlapevanja ter obe vrednosti primerjamo s skupnim letnim srednjim odtokom skozi izvire, dobimo podatek, da napajalno zaledje izvirov obsega površino približno 50 km2. Gre zgolj za približek, saj so omenjene vrednosti, z izjemo srednjega letnega odtoka skozi izvire, ocenjene na podlagi Koibenz & Pristovih (1998) izračunov. Za natančnejšo oceno velikosti zaledja bi bila potrebna sistematična merjenja izdatnosti izvirov in jasnejša opredelitev količine padavin ter izhlapevanja v zaledju, kot dveh pomembnejših dejavnikov napajanja. Hidrografsko zaledje izvirov sestavlja visoki kras Snežniške planote, ki je izoblikovan v dobro do srednje prepustnih krednih ter deloma jurskih in paleogenskih apnencih, dolomitih, apnenčastih in dolomitnih brečah, ki so tektonsko zelo pretrti, kar Še povečuje njihovo prepustnost (Šikič ef a/., 1972; Šikič & Pleničar, 1975). Podrobnejšo geološko zgradbo območja opisuje slika 7. V narivni zgradbi jugozahodne Slovenije kamnine pripadajo Snežniški narivni grudi (Placer, 1981). Ta je na svojem zahodnem robu narinjena prek flišnih plasti brkinske sinklinale, ki je del Komenske narivne grude. Dokaz za to sta tektonski okni pri Zagorju in Knežaku (Pleničar, 1968). Neprepustni fliš v podlagi prisili podzemne vode na dan v obravnavanih izvirih. Na območju izvirov gre tako za značilen primer kontaktnega krasa z manjšimi zatrepnimi dolinami. Tu in tam se na Snežniški planoti v omejenem obsegu pojavljajo tudi ledeniške morene in aluvialne naplavine. Večinoma gre za pesek in slabo zaobljen prod moren pobočnih ledenikov, ki so se v pleistocenu raztezali s Snežnika v različnih smereh (Šifrer, 1959). Snežniška planota se na zahodu in jugozahodu zaključuje s kraškim robom nad dolino Reke, na severovzhodu je omejena z Notranjskim podoijem, na severozahodu pa v blagem pregibu prehaja v kraško Zgornjo Pivko. Skupaj z javorniki na severu in Gorskim kotarjem na jugu in jugovzhodu tvori zaokroženo morfološko enoto s skupnimi značilnostmi. Večina površja na Snežniški planoti sega v višine med 1000 in 1400 m, najvišji vrh je Snežnik (1796 m). Območje je polno vrtač različnega nastanka in velikosti, brezen, med katerimi je Brezno Bogumila Brinška s 506 m globine najgloblje do sedaj odkrito ter značilnih kraško iedeniških globeli (Velika Padežnica, Vala, Grda draga ...). Kraške jame na območju niso znane. Snežniška planota pripada hidrološkemu tipu globokega raztočnega krasa. Za ta tip krasa je pomembna avtohtona padavinska voda, ki prenika v kraško podzemlje in odteka v različne smeri proti kraškim izvirom na obrobju. Snežniška planota je razvodno območje, saj se jugovzhodni del njenega ozemlja odmaka v porečje Riječine, severovzhodni in severni predeli pripadajo črnomorskemu povodju, zahodni predeli pa napajajo maloštevilne kraške izvire, ki prihajajo na dan ob stiku s flišem in so sestavni del porečja Reke. Možno je, da se skozi razpoke deloma kraško polnijo tudi manjši izviri narivnega kraškega roba jugovzhodno od Ilirske Bistrice. Ti se napajajo skozi apnenčasti pobočni grušč in nato izvirajo na točkah manjše prepustnosti ter sestavljajo desne pritoke Reke. Kljub dejstvu, da Reka s svojo dolino v višini približno 400 m oblikuje glede na preostalo obrobje Snežniške planote relativno zelo nizko lokalno erozijsko bazo, je količina podzemne vode, ki se usmerja v izvire proti zahodnemu robu Snežniške planote, dokaj majhna, Hidrografsko zaledje obravnavanih izvirov obsega tako le manjši del Snežniške planote, glavnina precej izdatnih padavin pa odteka v porečje Pivke (555 m) in Cerkniškega jezera (555 m) ter Riječine (350 m). Verjetno gre za vpliv geološke zgradbe v povezavi s tektonskimi strukturami in paleogeo-grafskim razvojem območja. 116 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 Gregor KOVAČIČ: KRAŠKI IZVIRI BfSTRSCE fjZ SLOVENIJA). H t-120 SI. 7: Geološka zgradba hidrografskega zaledja izvirov in njihovi potencialni onesnaževalci (prirejeno po: Šikič et ai.r 1972; Petauer et a/.,. 2002; Kovačič, 2001 b) Legenda: 1. Pobožni grušč (holocen), 2. Aluvialni nanosi (holocen), 3. Glaciofluvialni sedi men ti (pleistocen), 4. Flišni sedimenti: menjavanje glinovcev, laporovcev, peščenjaka, kalkarenitov, breč in konglomeratov (eocen), 5. Svetlosivi in sivi ter sivorjavi do črni apnenci do lapornati apnenci (paleogen), 6. Svetlosivi in beli prekristalizirani apnenci (zg. kreda), 7. Menjavanje plasti svetlih apnencev in dolomitov (zg. kreda), 8. Svetli apnenci (sp. in zg. kreda), 9. Dolomitno apnena breča (sp. in zg. kreda), 10. Apnenec in dolomit (sp. kreda) 11. Svetlosiv apnenec (zg jura), 12. Svetlosiv in temnosiv apnenec (zg. jura), 13. Temnosivi debelozrnati dolomit v menjavanju z apnencem (zg. jura), 14. Domnevni podzemeljski dotok vode, 15. Trap-športno strelišče, 16. Kamnolom, 17. Lokalna cesta, 18. Turistično naselje SviŠčaki, 19. Predlagana meja vodovarstvenega območja, 20. Kraški izvir. Fig. 7: Geological map of the karst springs' hinterland and their potential pollutants (after: Šikič et ak, 1972; Petauer et: ak, 2002; Kovačič, 2001b) Legend: Slope rubble (Holocene), 2. Alluvial sediments (Holocene), 3. Glaciofiuviai deposits (Pleistocene), 4. Flysch rocks: shales, marlstones, sandstones, calcarenites, breccias and conglomerates, 5. Light grey and grey limestones, grey brown and black limestones and marly limestones (Paleogene), 6. Light grey and white crystalline limestones (Upper Cretaceous), 7. Aletrnating light limestones and dolomites (Upper Cretaceous), 8. Light limestones (Upper and Lower Cretaceous), 9. Dolomite-limestone breccia (Upper and Lower Cretaceous), 10. Limestone and dolomite (Lower Cretaceous), 11. Light grey and dark grey limestone (Upper jurassic), 12. Light grey and dark grey limestone (Upper Jurassic) 13. Dark grey grained dolomite and limestones (Upper jurassic), 14. Suppositional underground water flow, 15. Trap-shooting ground, 16. Quarry, 17. Local road, 18. The Sviščaki tourist centre, 19. Suggested water-protection area, 20. Karst spring. FIZIKALNO KEMIJSKE LASTNOSTI IN MIKROBIOLOŠKA KAKOVOST VODE V IZVIRIH Meritve fizikalno kemijske in mikrobiološke kakovosti kraškega izvira Bistrica za potrebe upravljavca isto- imenskega zajetja pitne vode opravlja v okviru rednih in občasnih analiz Zavod za zdravstveno varstvo Koper v v nadaljevanju ZZV Koper). Nekaj podatkov o temperaiun vode v izvirih Bistrica, Sušeč in Kovačevec je objavil ludi Boegan (1938). Za natančnejšo podobo o fizikalno ke- 117 ANNALES • Ser. hist nat. • 13 • 2003 ■ 1 Gregor KOVAČ! Č: KRAŠKI IZViRi BISTRICE (IZ SLOVENIJA), I11-120 mijskih in mikrobioloških lastnostih obravnavanih kraških izvirov bi bilo treba opraviti sistematične meritve. Redne mesečne meritve fizikalno-kemijskib parametrov surove vode na zajetju kraškega izvira Bistrica, opravljene v letih od 2000 do 2002, kažejo na letno gibanje med 8,7 in 10,8 °C. Maloštevilni podatki za občasna izvira Sušeč in Kovačevec kažejo, da sta izvira nekoliko hladnejša, saj najnižja izmerjena vrednost znaša 7 °C (Boegan, 1938). Rezultati meritev SEP vode v zajetju za isto opazovano obdobje se sučejo med 324 in 388 pS/cm, pH vrednosti med 7,12 in 7,77. Enkratna meritev trdote vode kaže, da je karbonatna trdota vode v zajetju 10.9 "NT, nekarbonatna trdota pa samo 0,6 "NT, kar se ujema z geološko zgradbo zaledja izvirov. V litru vode je raztopljeno 55 mg kalcijevih in 10 mg magnezijevih kationov (ZZV Maribor, 1999; ZZV Koper, 2000-2002). % Zdrsmfvtno neusireztiiii vzorcev piini1 vnde .......................................-.....-....................j. — TT~ " n ~ "j— n 10 7 10 12 12 6 1992 1994 1996 1998 2000 2002 Str* r!« V/0T<1!\ in klv v/jjriinjil * V letu 2002 so zajele analize do vključno meseca julija. SI. S: Rezultati mikrobioloških analiz kraškega izvira Bistrica (Kovačič, 2001a; ZZV Koper, 2000-2002). Fig. 8: The results of microbiological analyses of water samples taken from the Bistrica karst spring (Kovačič, 2001a; ZZV Koper, 2000-2002). OGROŽENOST IN VAROVANJE IZVIROV Mikrobiološke lastnosti Izvira Bistrica kažejo, da je voda večinoma primerna za pitje tudi brez predhodnega čiščenja, medtem ko po fizikalno-kemijskih parametrih voda popolnoma ustreza kriterijem o zdravstveni ustreznosti pitne vode (SI. 8). Podobno kot večina drugih kraških izvirov je tudi voda v zajetju Bistrica občasno okužena z mikroorganizmi, zato je za kakovost pitne vode poskrbljeno s stalnim razkuževanjem na črpališču v neposredni bližini zajetja. Zaledje izvirov označuje razvit globoki kras Snežniške planote z dobro prepustnostjo. Zaradi pretakanja vode po razpokah in kanalih so pretoki kraške podzemne vode v primerjavi z nekraškimi podzemskimi zelo hitri In skrajšajo čas že tako omejenega biokemijskega čiščenja, kar slabša njeno kakovost. Zaradi dobre prevodnosti v kraških vodonosnikih skorajda ne prihaja do mehaničnega čiščenja, zato kraški izviri pogosto kalijo. Z vidika varovanja vode v izvirih je pozitivno dejstvo, da zaledje oblikujejo prostrani in neposeljeni gozdovi Snežniške planote, tako da je to zaradi reliefnih, podnebnih in geoloških značilnosti za kmetijsko rabo skrajno neprimerno območje. Kljub temu so izviri ogroženi zaradi gradbeniške, športne, turistične in gozdarske dejavnosti ter z njimi povezanega prometa v njihovem ožjem in širšem zaledju (SI. 7) (Kovačič, 2001 b). Ocene kažejo, da je koncentracija svinca v prsti, ki ga vsebujejo šibrnl naboji pušk, na aktivni površini športnega strelišča na Črnih njivah (to leži približno 700 m od izvira Bistrica na območju nekdanjega vojaškega strelišča) zelo velika. Za dosego mejne vrednosti letnega vnosa omenjene kovine (2,5 kg/ha), ki jo predpisuje Uredba o vnosu nevarnih snovi in rastlinskih gnojil v tla iz leta 1996 (UL RS, 1996), bi zadostovalo 150 izstreljenih nabojev letno. Dosedanje fizikalno-kemijske analize kakovosti vode iz izvira Bistrica kažejo, da je koncentracija svinca v vodi v mejah dovoljenih vrednosti, četudi strelišče obratuje že dve desetletji. Razširjene meritve fizikalno kemijskih lastnosti vode, ki jih na izviru Bistrica praviloma opravljajo dvakrat letno, kažejo na porast vsebnosti te kovine v vodi. junija 2002 je koncentracija svinca v vodi dosegla do 4 pg/l (mejna dovoljena vrednost za pitno vodo znaša 10 pg/l) (ZZV Koper, 2000-2002). Za zagotavljanje kakovostne pitne vode v kraškem izviru Bistrica in v sosednjih izvirih je potrebna preselitev športnega strelišča zunaj napajalnega območja izvirov ter sanacija s svincem onesnažene površine In prsti na strelišču. Turistično naselje Sviščaki (90 počitniških hiš) leži globoko v osrčju Snežniške planote, daleč stran od obravnavanih izvirov. Kljub temu ga avtorji strokovnih podlag za zavarovanje kraškega izvira Bistrice (Juren & Krivic, 1989; Petauer ef a/., 2002) uvrščajo v vplivno vodovarstveno območje. Varstvo kraške podtalnice bi morali zagotavljati z graditvijo neprepustnih greznic, ki jih večina objektov nima. Promet v povezavi z gozdarsko, turistično in gradbeniško dejavnostjo pomeni veliko grožnjo za zajetje, saj v njegovi neposredni bližini poteka lokalna cesta Ilirska Bistrica - Sviščaki, ki ni urejena tako, da meteorne vode s cestišča ne bi odtekale neposredno v vodonosnik. V hidrografskem zaledju izvirov sta dva kamnoloma. Spodnji, ki leži 200 m nad vodnim zajetjem, danes ne obratuje več. Danes v njem meljejo apnenec, ki ga do-važajo iz zgornjega kamnoloma. Kamnolom je danes nekakšno parkirišče za številne zavržene avtomobile ter delovno mehanizacijo in tovornjake, v njem pa se skrajno neprimerno skladišči nafta za pogon težke mehanizacije. Do pred kratkim je kamnolom rabil kot odlagališče odpadnega gradbenega materiala za širše območje Ilirske Bistrice. Pri kamnolomih je treba biti posebno previden pri vplivih na neposredni kraški odtok, kar pomeni, da je treba skrbno paziti, da se preprečijo kakršni koli izlivi nafte in olj ter drugih strupenih ali škodljivih snovi, saj bi vsakršno njihovo izlitje lahko 118 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 Gregor KOVAGO KRAŠKI UVIRI BISTRICE (jZ SlOVENSjA). II 1-120 daljnosežno vplivalo na kvaliteto kraške talne vode (Še-bela, 1997). Kemijske analize vode iz zajetja kažejo na občasno povečanje vsebnosti mineralnih olj v pitni vodi, ki skoraj dosegajo prag mejnih dovoljenih vrednosti (ZZV Koper, 2000-2002) in so dejansko lahko posledica neurejenih razmer pri gospodarjenju v kamnolomih. Sanacija spodnjega kamnoloma je nujna za dolgoročno zagotavljanje kakovostne pitne vode, obratovanje zgornjega kamnoloma pa je treba sanirati do stopnje, ko ne bo več ogrožalo kraške podtalnice (Kovačič, 2001 a). Kraški izvir Bistrica je zavarovan z Odlokom o določitvi varstvenih pasov in ukrepov za zavarovanje vodnih virov (PN Uradne objave, 39/1985), vendar so njegovi varstveni pasovi izdelani le na osnovi razdalj od zajetja, režim varovanja pa je v primerjavi z novejšimi metodologijami o zavarovanju podzemne pitne vode preblago in slabo definiran in se v glavnem ne uresničuje. Na podlagi hidrogeoloških raziskav zaledja so bile v letu 1989 (Juren & Krivic, 1989) in 2002 (Petauer et aL, 2002) izdelane strokovne podlage za zavarovanje kraškega izvira Bistrica. Nobena od predlaganih ni bila sprejeta z občinskim odlokom, kajti z novim Zakonom o vodah iz leta 2002 (UL RS, 2002) je določevanje vo-dovarstvenih območij pitne vode prešlo iz rok lokalnih oblasti v pristojnost države. Tako ostaja regionalno pomemben vir pitne vode praktično nezavarovan (Kovačič, 2001 a). ZAKLJUČEK Stalni in občasni kraški izviri v okolici Ilirske Bistrice so del enotnega hidrološkega sistema. Hidrološko za- ledje izvirov, ki obsega približno 50 km2, sestavlja ne-poseljena kraška planota Snežnik. Izviri se napajajo izključno kraško z avtohtono padavinsko vodo, površinskih tekočih voda in ponikalnic v zaledju ni. Posebnost izvirov je njihova razporeditev vzdolž narivnega roba ob zahodnem vznožju apniŠke Snežniške planote na eocenski fliš doline Reke. izviri značilno reagirajo na hidrološke razmere v zaledju s hitrim naraščanjem pretoka ter hitrim upadanjem, najprej v najviše ležečih izvirih. Fizikalno kemijske in mikrobiološke analize pitne vode iz kraškega izvira Bistrica, ki je zajet za vodo-oskrbo širšega območja, kažejo, da je voda precej kakovostna. V nenaseljenem gozdnem kraškem zaledju pa kljub temu najdemo nekaj resnih potencialnih in dejanskih onesnaževalcev kraške podtalnice. Zajetje pitne vode je sicer zavarovano, vendar so varstveni ukrepi slabo določeni in jih ne uresničujejo. Za boljše razumevanje hidroloških razmer je treba opraviti se vrsto nadaljnjih raziskav, analiz ter meritev. Pridobiti bi morali kakovostne in med posameznimi izviri primerljive podatke o fizikalno-kemijskih lastnostih vode. izpeljati bi morali natančna merjenja pretokov posameznih izvirov skozi primerljivo časovno obdobje ter preučiti hitrost odzivanja izvirov na padavinske dogodke v zaledju. Z zanesljivimi podatki o pretokih bi s pomočjo izračuna vodne bilance lahko približno določili velikost hidrografskega zaledja izvirov, katerega meje bi morali potrditi s sledilnimi poskusi. Z njimi bi pridobili tudi podatke o hitrostih in smereh pretakanja kraške vode v zaledju, kar bi pripeljalo do boljšega razumevanja hidrološkega sistema izvirov Bistrice, omogočilo pa bi tudi jasnejšo opredelitev vodovarstvenih območij. BISTRICA KARST SPRINGS (SW SLOVENIA) Gregor KOVAČIČ Faculty for Humanities Koper, University of Primorska, 51-6000 Koper, Glagoljaška 8 E-mail: gregor.kovacic@ihs-kp.si SUMMARY The Bistrica karst springs are distributed along the western foot of the Snežnik karst plateau (NW Dinarids) at the junction with the impermeable Eocene flysch of the Reka valley. Technically, the Snežnik karst plateau is part of the Snežnik thrust sheet, which is in its western part over-thrust to flysch layers. Deeply karstified Cretaceous and Jurassic limestones, dolomites and dolomite-limestone breccias prevail. Autochthonous precipitation water runs towards the karst springs situated in the margins of the plateau. The catchment area of the Bistrica springs stretches over a small part of the plateau. The estimated area is 50 km2. Permanent and periodical kaist springs are situated at an altitude of 420 to 470 m. During the dry period, the discharge of three of the springs reaches a total of only about 0.140 m3/s at the gauging station. After heavy rains, their discharge exceeds 36 m /s. The ratio between low, medium and high discharges is 1 : 36 : 830, but if the quantity of water tapped for water supply is calculated, this value is 1:12:254. It has been estimated that the mean annual discharge from the springs equals 1.85 m'/s. The time distribution of the mean monthly discharges shows that two annual maximums occur, the first in November and the second in April, while the lowest mean discharges 119 ANNALES • Ser. hist, nat • 13 ■ 2003 • 1 Gregor KOVAČIČ: KRAŠKI IZVIRI BISTRICE 5 ' okolje, prostor in energijo pripravil akcijo "Ohranimo želvo v slovenskem morju". Akcija, ki jo operativno vodi piranska enota Zavoda RS za varstvo narave, v njej pa sodelujeta tudi piranski akvarij in Morska biološka postaja Piran (Nacionalni inštitut za biologijo), je del partnerskega dogovora ministrstva in družbe Petrol pri ohranjanju in trajnostni rabi slovenskih voda. Za leto 2003 je bil tako pripravljen program aktivnosti, namenjenih v prvi vrsti obveščanju in ozave-ščanju vseh slovenskih ribičev in drugih uporabnikov slovenskega morskega prostora ter širše javnosti, zatem boljši organizaciji zbiranja podatkov in, nenazadnje, sprejetju uradnega nacionalnega akcijskega načrta varovanja morskih želv na osnovi pridobljenih podatkov. Z naštetim naj bi uresničili predvsem tri poglavitne, cilje projekta, in sicer: zmanjšali naključni ulov in pogin želv, pridobili več podatkov o ulovljenih želvah in prispevali k boljšemu poznavanju njihovih migracijskih poti, kritičnih habitatov, življenjskega ciklusa in biologije vrste nasploh. V skladu z navedenim sodeluje v projektu posredno tudi raziskovalec Hrvaškega priro-doslovnega muzeja iz Zagreba Bojan Lazar, nosilec programa Raziskovanje in zaščita že/v v Jadranu. Sedanji rezultati analize naključnega ulova, izsledki označenih osebkov in preliminarne analize prehrane kažejo, da je severni Jadran pomemben habitat te vrste v Me-diteranu. Ministrstvo za okolje, prostor in energijo ter družba Petrol sta ob začetku akcije poskrbela za tiskanje priložnostnih plakatov ter informativnih zgibank za ribiče in druge uporabnike morja, informacije o akciji so objavljene tudi na spletnih straneh ministrstva in družbe Petrol. Akvarij Piran Srednje pomorske šole iz Portoroža skrbi za sodelovanje z ribiči, za prevzemanje ulovljenih želv ter njihovo označevanje in izpustitev. Oblikovanje baze podatkov in ustrezna analiza slednjih pa je zaupana Morski biološki postaji. Podatki bodo po zaključku akcije posredovani Regionalnemu centru za zavarovana območja v Tunisu, koordinatorju Akcijskega načrta za varovanje sredozemskih morskih želv. Ob vsem navedenem pa družba Petrol za sodelovanje v akciji vsakemu, ki prinese želvo, podari tudi simbolično nagrado - priložnostno majico in 50 litrov goriva. foto: T. Makovec Na osnovi poročanja medijev in neformalnih razgovorov s predstavniki lokalnih skupnosti, različnih društev in s posamezniki lahko sklepamo, da so načrtovane aktivnosti naletele na ugoden odziv tako pri ribičih kakor tudi v širši javnosti. Pri tem velja posebej poudariti sodelovanje družbe Petrol oziroma njeno pripravljenost, da prevzame dejavno vlogo pri uresničevanju načel trajnostnega razvoja, katerih neločljivi del sta tudi skrb in zavzemanje za varovanje ogroženih vrst in ohranjanje biotske raznovrstnosti. V zgibanko smo zapisali - Želva išče prijatelje. Tokrat jih ni našla le v uradnih in neuradnih naravovarstvenikih, v piranskem akvariju ter ribičih, pač pa tudi v družbi Petrol. Robert Turk Valter Žiža Tihomir Makovec 125 ANNALES • Ser. hist. nat. • 13 • 2003 ■ 1 ocene. in poroč1la/recgn5ion1 e rei.azion¡/revsews and reports. 5 26-125 OCENE IN POROČILA RECENSIONI E RALAZIONI REVIEWS AND REPORTS Boris Sket, Matija Gogala, Valika Kuštor (ur.) 2003: ŽIVALSTVO SLOVENIJE. Tehniška založba Slovenije, Ljubljana, 2003, 664 strani. Spomladi leta 2003 je na knjižne police prišla obsežna monografija Živalstvo Slovenije. Knjiga je napisana na 664 straneh velikega formata. Uredili so jo Boris Sket, Matija Cogala in Valika Kuštor, izdala pa Tehniška založba Slovenije. Besedilo je prispevalo 40 avtorjev, vrhunskih domačih strokovnjakov na svojih področjih. Bogati slikovni material je delo 46 fotografov in 16 risarjev. Knjiga obravnava 88 strokovnih poglavij, vsako poglavje predstavlja neko širšo ali ožjo takso-nomsko skupino živali na območju, za katero radi pravimo, da je po Številu vrst eno bogatejših v Evropi. Osrednji del knjige je razdeljen na tri sklope: sklop nevretenčarjev, od katerih so z uredniškim posegom kot poseben sklop ločene žuželke, in sklop vretenčarjev. Vsak sklop ima svojo barvo, tako da jih ločimo že od daleč. S svojo barvo so označena tudi uvodna poglavja. Tu izvemo osnovne podatke o spremembah živalstva na ozemlju Slovenije od obdobja kambrija naprej ter o vlogi, ki jo je pri zoodiverziteti ime! in jo še ima človek. Spoznamo osnovne zakonitosti sistematskega razvrščanja živih bitij in nekaj dejstev o ogroženosti in varovanju živali pri nas. Ob koncu je v treh tabelah pestrost naših živali postavljena ob bok svetovni in pestrosti dveh sosednjih držav. Prvi strokovni sklop, ki so ga uredniki poimenovali Nižji nevretenčarji, obravnava 43 taksonomskih skupin (nekako na nivoju razredov), med katerimi najdemo pri nas slabo poznane čaškarje, kinorinhe, žive niti, po-časnike ipd., pa tudi bolj in dobro poznane spužve, pijavke, rake, če imenujem le nekatere. Količina napisanega besedila pri posamezni skupini je odvisna od števila poznanih vrst, predvsem pa od poznavanja skupine. Drugi sklop sestavlja, kot že rečeno, ena sama skupina, žuželke, ki pa so zaradi preglednosti razdeljene v 36 nižjih (nekako na nivoju redov) taksonomskih skupin. Glede na razmerje med številom vrst žuželk in številom vrst vseh drugih skupin nevretenčarjev je delitev kar smiselna. Zadnji sklop opisuje vretenčarje, ki so razdeljeni v devet nižjih taksonomskih skupin. Čeprav cenitve pravijo, da je vseh vretenčarskih vrst nekaj desetkrat manj kakor žuželčjih, so v knjigi predstavljene na le okoli pol manj straneh kot žuželke. To je pač skupina živali, ki jo najbolj poznamo in o kateri lahko veliko tudi napišemo. Po drugi plati pa je tudi očitno, da je število strani za posamezen sklop v veliki meri posledica odločitve, da knjiga ne bo znanstvena, ampak poljudno-strokovna publikacija s tudi ekonomskimi ambicijami. Pri knjigah takšnega kova pa je jasno, katere živalske skupine privabijo največ kupcev. Vsako poglavje večinoma predstavlja en živalski razred ali red. Začne se s kratko oznako skupine in značilnostmi telesne zgradbe ter ploditve, kjer so izpostavljene Se osnovne značilnosti, ki jih bo z lahkoto razumel vsakdo, ne glede na izobrazbo. Bralcu v pomoč so tudi številne skice. V odstavku o ekologiji dobimo osnovne podatke o tem, kje in kako živijo predstavniki skupine. Sledi odstavek o raziskanosti, kjer so predstavljeni posamezniki in institucije, ki so se in se še vedno ukvarjajo s skupino pri nas. Zelo primerna je tudi ocena o številu pri nas že poznanih vrst in o predvidevanjih, koliko jih lahko še pričakujemo. Že res, da so včasih napisane "prek palca" (natančnost ocene se močno razlikuje od skupine do skupine), a to je trenutno največ in najboljše, kar zmoremo. Ob koncu vsakega poglavja sledi še predstavitev vrst. Opisane niso vse, ki pri nas živijo, pa vendar dovolj, da lahko vsakdo dobi približen občutek o pestrosti živalstva na našem-ozemlju. IIIIBPI» V i^vrr \/f : .J-JS^ir:.}..Lj: :...'. .V ^ .. ' 'VRi i.(J- \ ^ Uredniki so k nastajanju knjige "Živalstvo Slovenije" pritegnili številne strokovnjake, ki so v besedila vložili ogromno znanja in dela. Mirno lahko zapišem, da je 126 ANNALES • Ser. hist. nat. • 13 • 2003 ■ 1 OCENE IN POROČI I.A/RECENSIONSE RRAZIONI/REVIEWS ANO REPORTS, 1 2G-I 29 kljub nekaterim pomanjkljivostim in visoki ceni vredna nakupa - če vas seveda živali zanimajo. Tolikokrat opevano pestrost slovenske favne nam prvič na tako celovit način polaga na dlan, za kar gre avtorjem, urednikom in navsezadnje tudi založbi vse priznanje. Res pa je tudi, da o skupini, ki vam je toliko pri srcu, da ste o njej že prebrali kakšno drugo knjigo, kaj dosti novega ne boste izvedeli. Sicer pa je to usoda vseh poljudno-strokovnih del, pri knjigi Živalstvo Slovenije pa vam kljub temu ostane še obilo novega na straneh tistih skupin, ki jih ne poznate. Davorin Tome Andrej Gogala: KAMEN, VODA, SONCE IN VETER. NARAVA KRASA iN SLOVENSKE (STRE. Prirodosiovni muzej Slovenije, Ljubljana, 2003, 176 strani. "Veter, pesek in zvezde" izpod peresa A. de Saint Exuperyja ... a!i pa *morje, sonce in veter", kot je zapisal umetnostni kritik Kastelic h katalogu Pfeiferjeve fotografske razstave o Sečoveljskih solinah, iste magične besede, ključne besede, kadar hočemo opis narave strniti, ga narediti vseobsegajočega in še osebnega hkrati: naslov Gogalove knjige je zato "v stilu" omenjenih dveh, in vse obljubljeno v naslovu bralec najde tudi v knjigi. Le redko je v eni osebi združen odličen fotograf, široko razgledan biolog, specialist entomolog in občudovalec pokrajine. Prav to je dr. Andrej Gogala, avtor knjige Kamen, voda, sonce in veter, ki je več kot fo-tomonografija, nekje med znanstvenim tekstom in esejem. V prologu nas avtor uvede v območje in temo, ki jo v knjigi obdela, nato pa v devetih poglavjih opiše posamezne pokrajinske enote od Visokega krasa do Sečoveljskih solin. Najbolj se avtor posveti kraškim pokrajinam, njihovi neživi in živi naravi. Vsak mtkro-svet je zgodba, ki ima rep in glavo, to je knjiga, v kateri ob lepih fotografijah ni neoprijemljivega leporečenja in "nakladanja". To je v slovenskem tisku precej v navadi pri opremljanju lepih fotografij: zelo pogosto oko vidi, razum pa ne dojame... Pri Gogalovi knjigi sta obe komponenti povsem enakovredno zastopani. Fotografije imajo za seboj biološko zgodbo, ki je načeta v likovni in dokončana v pisni obliki. Organizmi na fotografijah so določeni do vrste, avtor je poznavalec njihove biologije, neutruden opazovalec njihovih življenjskih navad, razmnoževalnih ciklov, vedenja ... pravi slovenski Faber.^: ; , . :; Kraški rob avtor domiselno poimenuje "slovenski koralni greben". Splošnim in strnjenim opisom narave avtor dodaja prenekatere izvirne in lastne neobjavljene entomološke podatke - prav presunljivo zveni npr. dejstvo, da je avtor našel na obravnavanem območju kar 317 vrst divjih čebel! Skozi drobne in natančne opise vrst, živalskih skupin in njihove razširjenosti nam pojasni, da je to območje biogeografsko na meji :med Celino in Sredozemljem, ki ga naseljuje : živelj: obeh velikih sistemov -■■ odtod takšna pestrost. V poglavju Voda na Krasu avtor poseže v geologijo, geomorfologijo in hidroiogijo: spoznamo nadzemne kraške pojave in nekaj njihovega življa. Avtor verjetno najraje obiskuje t.i. "Kraško in severno istrsko višavje" (Visoki kras), saj ga opisuje še posebej skrbno. Goli predeli Čičarije med Zbevnico in Kojnikom so avtorja privlačevali tako močno kot pisca teh vrstic. V knjigi se osebni vtisi mešajo z znanstvenimi spoznanji, vsepovsod pa je opaziti naravovarstveno noto in skrb za ohranitev tega območja. Naslednji sklop je dolina Dragonje, ki je nekakšno pilotno območje za celotno Slovensko Istro, zgrajeno iz flisne kamnine. Avtor v tekstu in fotografijah dobro povzame geomorfološke posebnosti reke, vegetacijske in floristične značilnosti in se posveti živalim in njihovim zgodbam. Če je kraški del kompletnejši, je del, ki je posvečen Istri, vsekakor preskromnega obsega; omejen je le na Dragonjo, čeravno bi si zaslužil več prostora. Zato pa so kot poseben sklop obdelane Se-čoveljske soline. O njih je bilo v zadnjih dveh desetletjih veliko napisanega in fotografiranega. Avtor se je v tem delu pravzaprav le dotaknil samosvojega sveta solin, izognil se je ponavljanju vsesplošno znanih dejstev in je zato teksta manj, zanimivi pa so odstavki od nižjih živalih, ki so bile na solinah doslej prezrte. I , Narava krctsa m slovenske Istre j 127 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 OCENE IN ROROČILVRECENSIONI E URAZiONl/REVIBA/S AND REPORTS, 5 26-5 29 Predzadnje poglavje je posvečeno sami morski obali, ki je posebnost že zaradi slikovitih flišnih klifov, ki tvorijo vse mogoče oblike in zaradi erozije neprestano spreminjajo svojo podobo. Tudi tu je manj poudarka na rastlinstvu, tekst je bolj skop in se posveča živalim. Zadnje poglavje - Radoživa jesen - je najbolj subjektivno obarvano, povzema jesenske podobe vseh opisovanih pokrajin, dodaja nove živalske zgodbe in se dotakne tudi človeka in rastlinskih kultur: oljke, vinske trte... Lahko poudarimo, da je knjiga občudovanja vredna že zaradi tehnično in estetsko dovršenih fotografij, tekst, ki je sicer kratek, pa je brez odvečnega leporečenja in ponavljanja znanih dejstev. Želeli bi si le, da bi bi! kraški del, ki je temeljiteje obdelan kot istrski, v prihodnje tekstovno še razširjen in dopolnjen z istrskim delom, toda to bi bila že druga knjiga... Mitja Kaligarič Ivan Gams: KRAS V SLOVENiji V PROSTORU IN ČASU. Založba ZRC, Ljubljana, 2003, 516 str. Ko je Stvarnik končal ustvarjanje sveta, mu je ostal še velik kup kamenja. Da bi kamenje nikomur ne bilo napoti, je sklenil, da ga vrže v morje. Vzel je veliko vrečo, vanjo natlačil kamenje, jo trdno zavezal, da bi vse skupaj proti morju zalučal. Zlodej pa, ki je nevoščljiv Bogu in ljudem, si je mislil: "Čakaj, gospod Bog, bom pa vrečo pretrgal." Ko je vreča letela visoko pod nebom, se je zlodej pognal do nje, naredil veliko luknjo. Kamenje se je usipalo po deželi, le malo ga je prišlo v morje. Tako je nastala kamnita dežela, naš Kras. (časopis jaslce, 1928, Mirko Skočir) Akademik Ivan Gams, doma iz Slovenj Gradca, redni profesor za fizično geografijo, praktično vse svoje življenje raziskuje površinske in podzemeljske kraške pojave, se ukvarja z geomorfologijo in klimatogeografijo slovenskega ozemlja ter s pokrajinsko ekologijo in regionalno geografijo Slovenije. Minilo je že skoraj trideset let od izida njegovega prvega monografskega opisa krasa v knjigi Kras, zgodovinski, naravoslovni in geografski oris. To je dolga doba glede na hitrost razvoja krasoslovja pri nas in po svetu, tako da je bila pričujoča knjiga več kot dobrodošla osvežitev. Knjiga Kras v Sloveniji - v prostoru in času je doslej najobšimejši in najbolj zaokrožen pregled našega krasa. Avtor nas vodi skozi osem poglavij, v katerih nas po- drobno, a nikakor ne suhoparno popelje v svet, ki je s svojimi nenavadnimi pojavi vzbujal zanimanje že v davni antiki. V poglavju Od kamna in Krasa do krasoslovja razloži izvor imena kras iz paleoevropske osnove kara, ki jo srečamo v številnih zemljepisnih imenih. Kras je s svojo posebnostjo navdihoval številne pesnike, od Livija in Plinija do Vergila in Danteja. Posebno pozornost pa namenjen raziskavam in opisom Cerkniškega jezera, ki je od nekdaj zbujalo pozornost njegovih raziskovalcev. Verjetno gre to pripisati povezanosti jezera s podzemljem, od koder naj bi, po Ciuverju (1580-1623), vodo prinašale race. S presihajočim jezerom so se ukvarjali številni "raziskovalci", od Kircherja in Valvasorja, ki razlaga princip polnjenja in praznjenja jezera z natego, do Nagla in Gruberja, ki zelo stvarno predstavi kraške pojave in teorijo o nastanku Cerkniškega jezera. Termin kras so, v različnih obdobjih, uporabljali za opis veliko različnih pojmov, kar je v knjigi zelo nazorno predstavljeno, od opisov, da je kras kamnita in puščavska pokrajina, do kompleksnih definicij, ki opredeljujejo kras kot ozemlje, kjer vlada zaradi poklinske prepustnosti kamnine podzemeljsko (kraško) pretakanje vode, učinkovito kemično raztapljanje kamnin in kjer so lahko razvite tudi značilne površinske in podzemeljske oblike. 128 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 OCENE IN POROČILA/RECENSIONI E RELAZIONI/REviEW5 AND RERORTS, s 26-? 29 Kras je deio vode, pravi avtor v poglavju Kraška hi-drografija. Kje pa je voda na krasu? Že od nekdaj je bila voda jedro sporov med prebivalci te sušne pokrajine, kjer je bila vsa skrb posvečena rabi vode iz izvirov, vse premalo pa so se ljudje ukvarjali z zajetjem padavinske vode na kraškem površju. Zelo zanimiva je primerjava krasa z živim organizmom, kjer ožilje ponazarjajo prevodniki, voda pa kri. Ob koncu tega poglavja je bralcu že povsem jasno, da je poleg kamna za kras bistvena voda. Ni krasa brez vode! S krasom so povezani številni hidrogeografski pojmi, od ponikalnic ali sušic, presihajočih jezer, ponorov, požiralnikov, do različnih izvirov, katerih imena govorijo o njihovi obliki, načinih nastanka in nenazadnje tudi o pokrajini in ljudeh, ki so jih tako poimenovali. Za tiste, ki so bolj doma v fizikalni kemiji, bo dobrodošlo poglavje o izredno kompleksnih kraških procesih, ki bi jih lahko opredelili kot neznatne spremembe, gledano s strani življenjske dobe človeka, z ogromnimi posledicami, gledano s strani življenjske dobe Zemlje. Bralca pritegne že sam naslov naslednjega poglavja jame, v katerih so nekdaj videli vhod v strašno podzemlje, danes pa iščejo v njih razvedrilo, zdravje in nova spoznanja. Avtor se pri opisu različnih funkcij jam skozi tisočletja ne omeji izključno na opis jam slovenskega krasa, marveč poda širok pregled tako v zgodovinskem, geografskem kot tudi kulturnem pomenu jam po svetu. Bistveno je razširjen opis raziskovanja jam, saj so se metode dela pri odkrivanju novih delov jam v zadnjih treh desetletjih zelo spremenile, predvsem na račun novih tehnik jamskega potapljanja in novih teorij o začetni fazi kraškega pretakanja. Siedi opis značilnosti kraškega reliefa z zelo slikovito razlago pojmov iz kraške terminologije. Človek je edina napaka Narave. iVVilha:;-. S. Giibert) Človek je istočasno sramota in ponos narave. (A; Pope) Človek spreminja kras, pravi Gams. Na splošno velja, da se danes kras spreminja iz puste in kamnite pokrajine v gmajne in gozdnate površine, ki zakrivajo tipično kraško geomorfologijo. Velik vpliv človeka pa se ne kaže samo v tem. Bistven za spreminjanje podobe krasa je tudi razvoj turizma, jame, ki so desetletja vzburjale človeka, niso več dovolj privlačne, zato gre razvoj v smeri novih turističnih destinacij. Poudarjen je tudi problem graditve cestnega omrežja in stavb, pri čemer se vse premalo upošteva biodiverzitetnost kraškega površja. Kljub vsemu pa avtor vidi upanje v naravovarstvenem osveščanju mladine in zavedanju posledic takšnega ravnanja za zdravo okolje. Novo v knjigi je tudi sedmo poglavje, kjer je predstavljena geološka preteklost razvoja krasa pri nas in po svetu. Preostali del knjige pa je namenjen podrobnemu regionalnemu pregledu krasa v Sloveniji. Dodani so daljši seznam strokovne literature, kraso-slovni slovarček, kazalo krasoslovnih pojmov, kazalo turističnih in drugih pomembnih jam ter povzetek v angleškem jeziku. Strokovno izrazje je prilagojeno širokemu krogu bralcev. Knjigo odlikuje pester izbor odličnih fotografij, geoloških kart, skic kraških pojavov in oblik ter jamskih profilov, ki bralcu, čeprav nestrokovnjaku s tega področja, pričarajo res celosten vpogled v to prečudovito pokrajino. Vsak, ki bo knjigo prebral, bo spoznal, kako je kras dejansko zelo kompleksen, da v krasu ne veljajo nobene splošno veljavne hipoteze in teorije. Kras je res nekaj izjemnega. Nataša Rezek Donev 129 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 KAZALO K SLIKAM NA OVITKU SLIKA NA NASLOVNICI: Zaradi globalnih klimatskih sprememb postaja voda čedalje pomembnejši naravni vir. (Loto: D. Podgornik) SI. 1 : Voda si utira pot skozi gosto tropsko vegetacijo. Slapičje v Nacionalnem parku Erawan Falls na Tajskem. (Foto: D. Podgornik) SI. 2: Morska želva kareta (Caretta caretta) je nedvomno ena najbolj znanih ogroženih vrst v Sredozemlju in razmeroma pogost obiskovalec v našem morju, kar sicer slovenski in tuji javnosti ni znano. (Foto: T. Makovec) Si. 3: Poleti leta 2002 so v vodah blizu Sentgaliie v jadranskem morju opazovali kita grbavca (Megaptera novaeangliae) in opazovanje tudi dokumentirali. To je prvi dokaz o pojavljanju te vrste v Jadranskem morju in šele šesti v celotnem Sredozemskem morju. (Foto: G. Stanzani) SI. 4: Gosti preplet obrasti, ki se je naselila na mrežastem cilindru, postavljenem ob ribji farmi v Piranskem zalivu (Slovenija). Prevladuje oranžni mahovnjak Shizobrachiella sanguinea in cevkasti mnogoŠčetinci. (Foto: S. Alaj-begovič) SI. 5: Osušeni in razpokam solinski bazeni v Sečoveljskih solinah (Slovenija) dajejo obiskovalcu vtis aridnega, puščavskega okolja. (Foto: D. Podgornik) SI. 6: Poginula rakovica na osušenih tleh, poraslih s sianušami. (Foto: T, Makovec) SI. 7: Spodnje Kriško jezero je eno izmed značilnih slovenskih visokogorskih jezer, ki so brez ledenega pokrova največ 5 mesecev v letu. (Foto: G. Muri) SI. 8: Nekatere predele, kot npr. Coloured Canyon na Sinajskem polotoku, dež namoči le enkrat na leto. (Foto: D. Podgornik) INDEX TO PICTURES ON THE COVER FRONT COVER: Owing to global climatic changes, water is becoming an increasingly important: natural source. (Photo: D. Podgornik) Fig. 1: Water making its way through thick tropical vegetation. Waterfall in Erawan Falls National Park, Thailand. (Photo: D. Podgornik) Fig. 2: Marine turtle (Caretta caretta) is no doubt one of the most endangered Mediterranean species and a relatively frequent visitor to our sea, a fact not well known to the Slovene and foreign publ ic. (Photo: T, Makovec) Fig. 3: In the summer of 2002, a humpback whale (Megaptera novaeangliae) was observed in the waters off Senigallia in the Adriatic. This is the first documented evidence of this species occurring in the Adriatic Sea and only the sixth for the entire Mediterranean. (Photo: G. Stanzani) Fig. 4: A thick interlacing of a fouling community (with predominant Shizobrachiella sanguine a and tubular brist-leworms) that has colonised a meshed cylinder submerged along a fish farm in the Bay of Piran (Slovenia). (Photo: 5. Alajbegovič) Fig. 5: Dry and cracked salt basins in the Sečovlje salt-pans (Slovenia) give a visitor the impression of an arid, desert-like environment. (Photo: D. Podgornik) Fig. 6: A dead crab on dry ground overgrown with halophilous plants. (Photo: T. Makovec) Fig. 7: The Lower Kriško jezero is one of the characteristic Slovene upland lakes that stay without their ice cover for 5 months in a year at the most. (Photo: G, Mud) Fig. 8: Some parts of the world, such as Coloured Canyon on the Sinai Peninsula, are thoroughly soaked by rain only once a year. (Photo: D. Podgornik) 130 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 NAVODILA AVTORJEM 1. ANNALES: Anali za istrske in mediteranske Študije - Anna/i d i Studi istriani e mediterranei - Annais for ¡stran and Mediterranean Studies (do 5. številke: Anali Koprskega primorja in bližnjih pokrajin - Annali del Litorale capodistriano e delle regioni vicine - Annais of the Koper Littoral and Neighbouring Regions) je znanstvena in strokovna interdisciplinarna revija humanističnih, družboslovnih in naravoslovnih vsebin v podnaslovu opredeljenega geografskega območja. 2. Sprejemamo prispevke v slovenskem, italijanskem, hrvaškem in angleškem jeziku. Uredništvo ima pravico prispevke jezikovno lektorirati. 3. Prispevki naj obsegajo največ 24 enostransko tipkanih strani s po 30 vrsticami. Na levi pustite 3 do 4 cm širok rob. Zaželjeno je tudi (originalno) slikovno gradivo, še posebno pa oddaja prispevka na računalniški disketi v programih za PC (osebne) računalnike. 4. Naslovna stran tipkopisa naj vsebuje naslov in podnaslov prispevka, ime in priimek avtorja, avtorjeve nazive in akademske naslove, ime in naslov inštitucije, kjer je zaposlen, oz. domači naslov vključno s poštno številko in morebitnim naslovom elektronske pošte. Uredništvo razvršča prispevke v naslednje kategorije: Izvirni znanstveni članki vsebujejo izvirne rezultate lastnih raziskav, ki še niso bili objavljeni. Dela pošlje uredništvo v recenzijo. Avtor se obvezuje, da prispevka ne bo objavil drugje. Pregledni članki imajo značaj izvirnih del. To so natančni in kritični pregledi literature iz posameznih zanimivih strokovnih področij. Predhodno sporočilo in Gradiva imajo ravno tako značaj izvirnih del. Strokovni članki prikazujejo rezultate strokovnih raziskav. Tudi te prispevke uredništvo pošlje v recenzijo in avtor se obveže, da prispevka ne bo objavil drugje. Poročila vsebujejo krajše znanstvene informacije o zaključenih raziskovanjih ali kratek opis strokovnih in znanstvenih knjig ali srečanj. Taki prispevki ne smejo presegati 5 strani. Mladinske raziskovalne naloge morajo biti urejene kot strokovna dela. Komentarji so namenjeni aktualnostim s strokovnega področja. Ne smejo presegati 2 strani. Obvestila so namenjena društvenemu življenju. Obsegajo 1 stran. 5. Prispevek mora vsebovati povzetek in izvleček. Izvleček je krajši (cca. 10 vrstic) od povzetka (cca. 30 vrstic) in v nasprotju s povzetkom tudi ne vsebuje komentarjev in priporočil. V izvlečku na kratko opišemo namen, metode dela in rezultate. Navedemo, čemu smo delo opravili ali na- pisali dokument. Na 2e objavljeno gradivo se sklicujemo le, če je to glavni motiv dela. Na kratko opišemo metode in tehnike dela - kolikor je potrebno za razumevanje. Nove tehnike opišemo le, kjer se razlikujejo od že znanih. Ce v delu ne opisujemo eksperimentalnega ali praktičnega dela, opišemo vire informacij. Rezultate in zaključke lahko združimo. Kar se da informativno navedemo le, kaj smo ugotovili oziroma odkrili. Povzetek začnemo s stavkom, ki vsebuje glavno sporočilo dela. Stavki naj bodo popolni in ne predolgi. Pišemo v tretji osebi, le izjemoma uporabimo glagole v neosebni obliki. Uporabljamo pravilni strokovni jezik in se izogibamo slabše znanim kraticam. Ohraniti moramo osnovno informacijo in poudarke iz glavnega besedila. V povzetku ne sme biti ničesar, česar glavno besedilo ne vsebuje. 6. Avtorji so dolžni definirati in pripisati ustrezne ključne besede (pod izvlečkom) članka. Zaželjeni so tudi angleški (ali slovenski) prevodi ključnih besed, podnapisov k slikovnemu in tabelarnemu gradivu. Priporočamo se še za angleški (ali slovenski) prevod povzetka, sicer bo za to poskrbelo uredništvo. 7. V besedilu se po možnosti držimo naslednjih poglavij: 1. Uvod. 2. Pregled dosedanjih objav. 3. Materiali in metode (Dokazni postopek). 4. Rezultati. 5. Razprava ali diskusija. 6. Zaključek (Sklepi). 7. Zahvala - če avtor želi. 8. Priloge - če je potrebno. 9. Literatura (Viri, Bibliografija). 10. Povzetek (Summary). 11. Izvleček. 12. Ključne besede (neobvezno). 8. Ločimo vsebinske in bibliografske opombe. Vsebinske opombe besedilo še podrobneje razlagajo ali pojasnjujejo, postavimo jih pod črto. Z bibliografsko opombo pa mislimo na citat - torej sklicevanje na točno določeni del besedila iz neke druge publikacije (navedemo tudi točno stran, kjer je citat objavljen) ali na publikacijo (članek) kot celoto (točne strani, kjer smo besedilo prevzeli, ne navajamo). Bibliografsko opombo sestavljajo naslednji podatki: Avtor, leto izida in - le če citiramo točno določeni del besedila - tudi navedba strani. Celotni bibliografski podatki citiranih in uporabljenih virov so navedeni v poglavju Literatura (Viri, Bibliografija). Primer citata med besedilom: (Grafenauer, 1993, 11). Primer navajanja vira kot celote, brez citiranja: {Grafenauer, 1993). 131 ANNALES • Ser. hist. nat. ■ 13 ■ 2003 ■ 1 Popolni podatki o tem viru v poglavju Literatura pa se glasijo: Grafertauer, B. (1993): Miti o "Istri" in resnica istrskega polotoka. V: Acta H i stri ae I. Koper, Zgodovinsko društvo za južno Primorsko, 9-52. Če citiramo več del istega avtorja iz istega leta, poleg priimka in kratice imena napišemo še črke po abecednem vrstnem redu, tako da se viri med seboj razlikujejo. Primer: (Crafenauer, 1993a); {Grafenauer, 1993b). Bibliografska opomba je lahko tudi del vsebinske opombe in jo zapisujemo na enak način. Posamezna dela ali navedbe virov v isti opombi ločimo s podpičjem. Primer: (Gombač, 1996; Grafenauer, 1993b). 9. Pri citiranju arhivskih virov navedemo najprej arhiv, nato ime fonda ali zbirke in signaturo. V članku navajamo kratico arhivskega vira v oklepaju med besedilom. Kratico pa razložimo v poglavju o virih na koncu prispevka. Primer navajanja arhivskega vira v oklepaju med besedilom: (PAK. RAC, 1) Primer navajanja arhivskega vira v poglavju o virih: PAK. RAG - Pokrajinski arhiv Koper, Rodbinski arhiv Gravisi, a. e. (arhivska enota) 1. Podobno poskušamo ravnati pri uporabi časopisnih virov. 10. Poglavje o literaturi in virih je obvezno. Bibliografske podatke navajamo takole: - Opis zaključene publikacije kot celote - knjige: Avtor (leto izida): Naslov. Zbirka. Kraj, Založba. Npr.: Verginella, M., Volk, A., Colja, K. (1995): Ljudje v vojni. Druga svetovna vojna v Trstu in na Primorskem. Knjižnica Annales 9. Koper, Zgodovinsko društvo za južno Primorsko. V zgornjem primeru, kjer je avtorjev več kot dva, je korekten tudi citat: (Verginella et al., 1995) Če navajamo določeni del iz zaključene publikacije, zgornjemu opisu dodamo še številke strani, od koder smo navedbo prevzeli. - Opis prispevka v zaključeni publikaciji - npr. prispevka v zborniku: Avtor (leto izida): Naslov prispevka. V: Avtor knjige: Naslov knjige. Izdaja. Kraj, Založba, strani od-do. Primer: Verginella, M. (1995): Poraženi zmagovalci. Slovenska pričevanja o osvobodilnem gibanju na Tržaškem. V: Verginella, M. et al.: Ljudje v vojni. Druga svetovna vojna v Trstu in na Primorskem. Knjižnica Annales 9. Koper, Zgodovinsko društvo za južno Primorsko, 1 3-51. - Opis članka v reviji: Avtor (leto izida): Naslov članka. Naslov revije, številka. Kraj, Založba, strani od-do. Primer: Gombač, B. (1996): Osvoboditev Trsta maja 1945. Annales 8/'96, Koper, Zgodovinsko društvo za južno Primorsko - Znanstvenoraziskovalno središče Republike Slovenije Koper, 141-150. - opis ustnega vira: Informator (leto izporočila): Ime in priimek informatorja, leto rojstva, vloga, funkcija ali položaj. Način pričevanja. Oblika in kraj nahajanja zapisa. Primer: Baf, A. (1998): Alojzije Baf, r. 1930, župnik v Viži-nadi. Ustno izporočilo. Magnetofonski zapis pri avtorju. - opis vira iz internetnih spletnih strani: www. home page ustanove (leto-mesec izpisa): celoten naslov podstrani. Primer: www.zrs-kp.si (2000-07): http://www.slo-istra.comAoper/zrs/zrs.htm! Članki so razvrščeni po abecednem redu priimkov avtorjev ter po letu izdaje, v primeru da gre za več citatov istega-istih avtorjev. 11. Tiskarski znaki za poudarke naj bodo: podčrtano za polkrepko, valovito podčrtano za ležeče. Računalniški zapis naj vključuje ustrezne oznake za bold in italics. 12. Kratice v besedilu moramo razrešiti v oklepaju, ko se prvič pojavijo. Članku lahko dodamo tudi seznam uporabljenih kratic. 13. Pri ocenah publikacij navedemo v naslovu prispevka avtorja publikacije, naslov, kraj, založbo, leto izida in število strani (oziroma ustrezen opis iz točke 10). 14. Prvi odtis prispevkov uredništvo pošlje avtorjem v korekturo. Avtorji so dolžni popravljeno gradivo vrniti v treh (3) dneh. Besedilo popravljamo s korekturnimi znamenji, ki jih najdemo na koncu Slovenskega pravopisa (1962), Ljubljana, ali v: Slovenski pravopis 1. Pravila (1990). Ljubljana, SAZU-DZS, 13-14. Širjenje obsega besedila ob korekturah ni dovoljeno. Druge korekture opravi uredništvo. 15. Uredništvo prosi avtorje, naj navodila vedno upoštevajo. Ob vseh nejasnostih je uredništvo na voljo za vsa pojasnila. UREDNIŠTVO 132 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 INSTRUCTIONS TO AUTHORS 1. ANNALES: Annals for ¡stran and Mediterranean Studies - Anali za istrske in mediteranske študije (up to No. 5: Annals of the Koper Littoral and Neighbouring Regions - Anali Koprskega prirnorja in bližnjih pokrajin) is a scientific and research interdisciplinary review covering the humanities, sociology and natural science in the area as stated in the review's subtitle. 2. Articles (papers) written in Slovene, Italian, Croatian and English languages will be accepted. The Editorial Board reserves the right to have them linguistically revised and corrected. 3. Articles should be written on max. 24 pages with double spacing and on one side of the sheet only. On the left side of each page, a 3-4 cm wide margin is to be left. Original photographs, drawings and tables are welcomed, as well as diskettes containing the texts, together with reference to the programme used. 4. Title page of typescript is to include title and subtitle of the article (paper), author's name, any (academic) titles and name of institution by which employed or personal address with eventual E-mail address. Articles are arranged in the following eight categories: Original scientific papers containing not yet published results of the author's own research. Such works will be reviewed by scientists chosen by the Editorial Board. Authors oblige themselves not to offer their material to any other journal or magazine. Review articles bearing the character of original works. 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Abstract is the shorter of the two (with up to 10 lines) and does not include, in contrast to summary {with up to 30 lines), explanatory comments and recommendations. Abstract is to contain a short description of the purpose and methods of the work and its results. Author should also state why the work has been carried out and why a document has been written about it. References to the already published material are made only if this is the main purpose of the work. Methods: if necessary, work methods and techniques are to be briefly described (new techniques are to be stated only if differing from the already known ones). If no experimental or practical work is described, sources of information are to be given. Results and conclusions may be incorporated. Findings are to be presented as briefly as possible. At the beginning of summary the essential points of the carried out work are to be presented. Sentences should be concise and not too long. The text is to be written in the third person; verbs may be used in impersonal form only exceptionally. The not so well known abbreviations are to be avoided. Summary is to retain the basic information from the main part of the text, and should not contain anything that does not appear in the main text itself. 6. Authors are obliged to define and state key words (below abstract) in their articles. English (or Slovene) translation of key words, texts accompanying figures and tables are welcomed, as well as English (or Slovene) translation of abstracts; if this is not convenient, the Board of Editors will provide for it. 7. Texts should include, if at ail possible, the following chapters: 1. Introduction 2. Works published to date 3. Material and methods 4. Results 5. Discussion 6. Conclusions 7. Acknowledgements (if desired by author) 8. Supplements (if necessary) 9. References (Sources, Bibliography) 10. Summary 11. Abstract 12. Key words 8. Two kinds of notes are distinguished: those regarding the contents of the text, and those referring to bibliography. The first elucidate the text in even greater detail and are to appear at the bottom of the page (under line). Bibliographical notes, which are to appear in brackets in the text itself, deal with quotations and refer to a precisely stipulated part of the text from some other publication (the page on which quotation appears is to be therefore stated as well) or to a publication (article) as a whole (in this case no page from which the text has been taken is to be stated). Bibliographical notes are made up of the following details: Author, year of its publication, and page (but only if a precisely stipulated part of the text is quoted). The entire bibliographical data of the quoted and used sources are to be stated under References (Sources, Bibliography). Example of quotation referring to a precisely stipulated part of the text: (Sommerville, 1995, 11). 133 ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 Example of source quotation as a whole, with no citation: (Sommerville, 1995). The entire data of this source are to be stated in the references and sources chapter as follows; Sommerville, M. R. (1995): Sex and Subjection. Attitudes to Women in Early-Modern Society. London-New York-Sydney-Auckland, Arnold. [f a number of works by the same author from the same year are quoted, letters in alphabetical order are to be stated apart from the author's surname and abbreviation of his first name, in order that the sources are clearly divided between each other. Example: (Sommerville, 1986a); (Sommerville, 1986b). Bibliographical note can also be a part of the note referring to the contents and is to be written in the same way, i.e. in brackets within the note referring to the contents. 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The second (printing) proofs will be read by the Editorial Board. 15. Authors are kindly requested to consider these instructions at all times. In case of any indistinctness, please do not hesitate to contact the review's Editorial Board. EDITORIAL BOARD 134 Anali za istrske in mediteranske študije Annali di Studi istriani e mediterranei Annals for J strain and Mediterranean Studies series historia naturaiis, 13, 2003, 1 Supplement BIQFAQs BIOFiltration and AQuacnlture: an Evaluation of Substrate Deployment Performance with Mariculture Developments FA Baas. F S1 kfwámn stí \¡*v ¡s¡ National Institute of Biology, Marine Biology Station Piran, Slovenia institute of Marine Biology of Crete, Greece Israel Océanographie and Limnological Research Ltd., Israel University of Haifa, Israel Natural Environment Research Council, UK University of Portsmouth Higher Education Corporation, UK University of Southampton, UK ANNALES • Ser. hist. nat. - 13 • 2003 - 1 ■ Supplement Anali z!w forte: psstrirution of the food surplus and fae.cai partoes on the si;as ed below a fish farm ., j.g INTRODUCTION Fish farming, in comparison to fishing of the wild stocks, has economic advantages, but it also presents a threat to the ecoiogical equilibrium in the marine environment. Different influences are coming from the maricLilture in a form of the food supply surplus, solid and dissolved excrements, and as a wide range of different pharmaceutical drugs. There are two types of particles that enter the ecosystem from the fish farm: the fish food surplus, that is the part of the food supply that is not consumed by fish and passes through the nets of the cage, and fish excrements. This process increases the consumption of dissolved oxygen (short-term impact) and the accumulation of decayed material in the upper layer of the sediment. The latter process is considered as a long-term impact since this material at the surface film of the seabed is later regenerated. This means that proper planning of the fish farm location should consider the amount of particles deriving from the farm and their spreading around the cages. The paper presents the simulation of the distribution of food surplus particles and faecal pellets on the seabed due to the horizontal advection of the water mass during their sinking below the fish farm. MATERIALS AND METHODS The shallow Bay of Piran (Fig. 1) is part of the north- ern Adriatic Sea and is opened to the Gulf of Trieste. The depth beneath the cages is 13 ± 1 m; depth variations are caused mainly by tides. The sea floor is smooth and muddy, with a moderate declination towards the open sea. The water column structure resembles that of the Gulf of Trieste (Malacic, 1991) with seasonal temperature variations. However, at the fish farm site the influence of the river Dragonja modifies the vertical stratification in the shallow water column, in particular the distribution of salinity. Records of monthly data collected at the two nearby stations that are less than 1.5 km away (Tab. 1) show that during the spring-summer time (Forte, 2001} temperature in the upper part of the water column varies between 18-26 "C, and between 12-17 °C in its lower part. Salinity also shows some seasonal variations, although less pronounced, for it varies between 28.0 ..... 38.S PSU in the upper part of the water column. Currents were measured on the fish farm site (4S°29.226' N, 13°34.838' E) with the acoustic Doppler current-meter profiler of Nortek AD company (NDP) mounted on the sea floor. The instrument scans the water column above with three beams and outputs the velocity of layers that are 1 m thick. The average period of currents was 600 s, while the sampling period was 3600 s. Measurements were performed in the spring-summer period, from 19 April to 4 July and from 31 July to 31 August 2000. ! ^ ■ •x-V--. f K - V Gu If off iest« ■IZOLA" [ pjSAN Fig. 1: Location map of the fish farm and the nearby measurement stations MA (45°30.20' N, 13°34.20' E, depth 16 m) and 35 (45°29.40' N, 13n35.00' E, depth 12 m) from where the long-term temperature and salinity records were applied for the estimate of density on the farm site. SI. 1: Sldca lokacije ribogojnice in bližnjih merilnih postaj MA (45°30.20' N, I3°34.20' E, 16 m) in 35 (45"29,40' N, 13"35.00' E, 12 m), kjer so bile opravljene dolgoročne meritve temperatur in slanosti za kasnejši izračun gostote morske vode. ANNALES • Ser. hist. nat. • 13 - 2003 • 1 • Supplement Vlado MALAČIČ & U-mvz FORTE: DISTRIBUTION OF i HT FOOE) SURPLUS ANO FAECAL PARTICLES ON THE 5EABED BELOW A FISH FARM ..., 3-8 Tab. 1: Simple statistics of 1362 temperature and salinity data obtained in 25 years in the Bay of Piran (1975-2000). The average value is denoted with < >, and deviation with SO. Sampling was performed at stations 35 and MA and at four different depths: on the surface, at depths ranging from 5 to 10 m, and just above the sea floor (Ruttner sampling). Tab. 1: Osnovni statistični podatki o temperaturah in slanostih, izračunani iz 1362 meritev, pridobljenih v 25 letih (v obdobju 1975-2000) v Piranskem zalivu. Znak < > označuje srednjo vrednost, SD pa standardno de-viacijo. Meritve so bile napravljene na postajah 35 in MA na štirih globinah (površina, 5 m, 10 m in tik nad dnom ~ Rutine rje v vzorčevalntk). T (5 C) S (PSU) Ot (kg/m3) < > 15.67 36.88 27.16 SD 5.42 1.02 1.73 Min 5.85 28.77 20.69 Max 27.63 39.83 30.89 Sinking velocity of fish food and fish excrements was measured in the lab. Measurements of the sinking velocity of fish food were performed in a plastic cylinder filled with seawater with salinity of 37.5 PSU and temperature of 22.5 °C. This seawater density is thereafter calculated as 25,9 kg/m3. From twelve throws of fish pellets, the highest and the lowest measured velocity were eliminated; from the remaining ten values the average and the standard deviation (SD) were calculated. We combined the sinking velocity of fish food with the current-meter data to predict the distribution of uncon-sumed fish food on the seabed below fish cages. This idea of simulating the distribution of uncon-sumed fish food was extended to faecal particles. For this reason, faeces were collected from the fish cage using a particular trap of polyethylene foil. The foil covered an area of 1 trr at the bottom of the cage, with a plastic bottle attached in its centre as a recipient of the sinking material. In the laboratory, a sample of collected particles with a volume of 1.5 I was diluted to 5 I and carefully mixed to achieve more homogeneous distribution of excrement. From this mixture, a sub sample of 5 ml was taken and released into another plastic cylinder, in which the sinking velocity was measured. This second cylinder was filled with seawater collected a few miles away, with temperature of 22.0 °C, salinity of 38.5 PSU, and the calculated density of 26.9 kg/m3. RESULTS AND DISCUSSION In the year 2000, currents at the fish farm were, measured twice, in the late spring (19 April - 5 July) and summer (31 July-31 August 2000) periods. Frequenc ies of the directions of currents show (Forte, 2001) that in late spring the prevailing currents over the whole water column were directed towards NE and E (30% - 40%), while they were more evenly distributed during the summer, with more frequent directions towards NW, W and SW (15% - 20%). in both cases, the frequency of directions towards the south was not higher than 10%, indicating that over the entire water column the currents were mostly oriented away from the mouth of the Dragonja river (Fig. 1) during the spring-summer period. The distribution of velocity magnitude in different directions (eight sectors) show higher values of currents in NE and E directions during late spring, while during the summer period currents had evenly distributed magnitude in all directions. Currents in the surface layer 11 m above the NOP and about 2 m below the sea-surface deviated from the rest of the water column during the spring period. The most, frequent directions then were to the E or W, and their velocities reached values of 0.17 m/s in the W direction and of 0.15 m/s in the E direction. During the summer period, however, surface currents had similar directions as the rest of the water column. This indicates that the surface layer is dominantly wind-driven, since during the spring period the wind is more frequent than during the summer (Ogrin, 1995), while in the rest of the water column tidal and density driven currents prevail. Tab. 2: Sinking velocities (mean±SD) of fish food pellets and faecal particles, measured in the lab. Seawater density for the experiment with pellets was 25.9 kg/m3 and density for the experiment with faecal particles 26.9 kg/m3. Tab. 2: Hitrosti padajočih delcev ribje hrane in delcev ribjih iztrebkov (srednja vrednost+SD). Meritve so bile opravljene v laboratoriju. Gostota morske vode med poizkusom z ribjo hrano je bila 25,9 kg/m3, medtem ko je bila gostota med poizkusom z delci iztrebkov 26,9 kg/m3. Sinking ve ocity (cm/s) Pellets Faeces < > 5.72 0.64 SD 0,15 0.05 Sinking velocities of food pellets were estimated in the lab as 5.7 ± 0.15 cm/s (Tab. 2). In comparison to food pellets, the sinking of faecal particles was significantly slower. Their sinking velocity was estimated at 0.64 ± 0,05 cm/s, being roughly 8.9 times smaller than that of food pellets. This means that through the water column of the same density as the one of the seawater in lab cylinder, food pellets would pass vertically through a layer of thickness of 1 m in less than 18 s, and would reach the sea floor from the surface in less than 3.8 minutes. Faecal particles would travel through a 5 ANNALES • Ser. hist. nat. • 13 • 2003 • T • Supplement Vlado MAiAOČ & |are?z FORTE: DISTRIBUTION OF THE FOOD SURPLUS AND fAECAI. PARTSO.ESON THE SEABED 6ELOW A FISH FARM .... 3-8 layer of 1 m on average in less than 157 s, and would reach the sea floor in less than 34 minutes. Since currents were measured with a sampling rate of 1 hour, we reasonably assumed that both types of particles were sinking through the water column during the single measurement cycle, and that the sampling period of 10 minutes represents currents during the sinking period of half an hour. It is estimated that the range of sinking speed is larger due to the unknown densities of the water column, food pellets and faecal particles, and due to the unknown geometry of the latter during the entire measurement period. We may reasonably suppose that food pellets and faecal particles of density p;> are sinking laminarly with a constant speed within a layer of a constant density p. In the balance of forces that act on sinking particles, a problem arises with the friction force, since the geometry of food pellets and faecal particles is not sufficiently known. However, we may qualitatively describe the linear friction law (Kundu, 1990) that holds for the low Reynolds numbers (Re = vd/i], where v is the sinking speed, dthe typical dimension across the particle, and i] = 10 s m3 s is the kinematic viscosity at 20 °C). It is estimated that Re is smaller than 300 for food pellets (v = 0.06 m/s and d < 5 10'3 m), and that Re is below 13 {v = 6.4 10"3 m/s and d < 2 10"3 m) for faecal particles. This indicates that the linear dependence of friction force on the sinking velocity is applicable and the friction force is parameterised as Kp(> rj d v, where K is the dimension-less constant that accounts for geometry {K = 6 n foi sphere-like particles). The balance between the buoyancy force (pj, - p)gV {g - 9.81 m/s2 is the gravity acceleration and V the volume of a particle), and the friction force yields the sinking velocity as: , K^R Krjpd This means that if the density of a sinking particle pp is known, the sinking speed is decreasing with the ambient density in an inverse linear way, proportional to 1/x -pjpp, where x ~ pjp is the ratio of densities, with p0 being the density at which the sinking speed was measured. The density is related to the density excess a-f as p = 1000.0 + N +0.4 and +20.3%», respectively. Untreated GF/C filters and empty tin capsules were used as blanks. Samples were analysed in triplicate to assess the precision and the reproducibility of the analyses. Standard deviation of the measurement determined on multiple analyses of working standards was generally < 0,2%>, while standard deviation of the samples was generally better than < 0.3%«. RESULTS AND DISCUSSION Average S'^N values of particulate organic matter and fouling communities at reference locations and fish farms in Crete, Eilat and Piran are listed in Table 1. POM was enriched in 'SN at the fish farms compared to the reference locations at all sites, as a consequence of the presence of ,SN enriched organic debris originating from the cages (faeces with average 815N between 7 and 10.6%0, remains of fish food with S,5N values between 7.6 and 9.7%o). An exceptionally high enrichment in 1SN in POM was detected in Crete, where the large difference cannot be attributed only to the presence of organic: waste from the farm, but is partially related to the seasonally dependent differences in nitrogen isotopic composition of plankton, where 5,SN values can change by several per mil related to the temperature-dependent nitrogen cycling (Minagawa & Wada, 1984; Sigleo & Macko, 1985; Nakatsuka ef ai, 1992; Mon-toya, 1994; Altabet eta/., 1999). The high average 8,SN value is a consequence of extreme enrichment of POM in ,5N in July 2001, when 655N values of 11-13 %> were determined. Later on the 5,SN ranged from 7.2 to 8.6 %o, yielding a seasonal average of 9.2 %>. Tab. 1: Average S,sN values of particulate organic matter and fouling communities at reference locations and fish farms in Crete, Eilat and Piran. Tab. I: Povprečne vrednosti SisN suspendiranih organskih snovi in združbe obrasti na referenčnih lokalitetah in v ribogojnicah na Kreti, v Eilatu m Piranu. Location S!5N of POM 655N of fouling community [%«] CRETE Reference 4.2 4.5 Fish farm 10.8 (9.2*) 6.3 EILAT Reference 3.6 (3.8*) 3.6 Fish farm 4.8 (4.9*) 5.7 | PIRAN Reference 5.3(4.7*) 6.7 Fish farm 5.8J5.7*) ___ 5.7 ♦seasonal averages 10 ANNALES • Ser. hist nat. • 13 ■ 2003 • 1 • Supplement Sonja LOS FN el tl.: 'SN ENRICHMENT IN FOULING COMMUNITIES INFLUENCED BY ORGANIC WASTE DERIVING FROM FISH FARMS, 9-12 Fouling communities at reference locations were enriched in l5N relative to the POM at all three sites, where the enrichment in Eilat was within the analytical error of the measurements. An enrichment of fouling communities in '^N at the fish farms relative to the reference locations was observed in Crete and Eilat, while in Piran the opposite occurred. The relation of 5,SN of POM to 5,SN of fouling communities at the fish farms, however, seems controversial. The organisms are enriched in tsN relative to their food sources by at least 1.3%o, depending on the species (Minagawa & Wada, 1984), therefore the observed enrichment can be used for an overall estimation of the sources of nutrition of fouling organisms. Where the organisms are enriched in 1SN relative to the POM, at least part of their nutrition derives from this source. Where the enrichment is very small or even negative, it is obvious that the particulate organic matter does not contribute to the average organisms' diet. Since the colonising communities are composed of different species, only average particulate nitrogen consumption of the whole community colonising the analysed biofiiter can be detected. ^N-enrichment of organisms at the fish farms relative to those at reference locations indicates that some of the incorporated nitrogen derives from the fish farms, however, its fractions depend mostly on the composition of the colonising community, i.e. relative abundance of non-selective suspension feeders, which are able to ingest and retain nitrogen from particles of various sizes. In Crete, the fouling community at the fish farm is clearly enriched in 1SN relative to the reference location, however, depleted in i5N relative to the POM. That means that suspension feeders present only a minor fraction of the whole community. Similar situation was observed in Piran. Figure 1 shows the enrichment of fouling communities relative to the POM at the fish farms and at reference locations. Different enrichments between POM and fouling communities at the fish farms and at reference locations show that the compositions of fouling communities at both locations were obviously different and highly variable from biofilter to biofilter, as well as seasonally, which can be seen from the large range of measured 51SN values. Therefore they cannot be directly compared to each other. However, the overall enrichment of the organisms at the fish farms relative to the reference locations in Crete and Eilat shows that they are enriched in tsN, i.e. at least part of their food is represented by 1SN enriched POM deriving from the cages. 14- 13- reference locations 12- 11- > 8- i v ^ 7- m o -if- Z 6" Í 5-co 4- 3 2- s -H- 1 -A V 1- i I X a ¿ > Crete Eilat Piran Fig. 1: $,SN of particulate organic matter and fouling communities at the fish farms and at reference locations; solid symbols = POM, open symbols = fouling community. Horizontal bars represent average values of all measurements. SI. T; S,sN suspendiranih organskih snovi in združba obrasti v ribogojnicah in referenčnih lokalitetah; polni simboli = POM, odprti simboli = združba obrasti. Horizontalni stolpiči ponazarjajo povprečne vrednosti vseh meritev. 11 ANNALES • Ser. hist. nat. • 13 • 2003 • 1 • Supplement Sonja lOlEN e/ ,iL- UN ENRtCHMFNT IN VOUUNG COMMUNITIES INEI.0ENCED BY ÛRCANIC WASTE DERIVING EROM EISH fARMS. 9-12 ~~ IZOTOPSKA SESTAVA DUŠIKA V MORSKIH ORGANIZMIH V VPLIVNEM OBMOČJU RIBJIH EARM Sonja LOJEN institut "Jožef Stefan", Odsek za znanosti o okolju, Sl-iOOO Ljubljana, Jamova 39 E-mail: sonja.lojen@ijs.si Dror ANGEL & Timor KATZ National Centre for Maricufîure, Israël Océanographie and UiTinological researeb, [L-Eiiat 88112, POB 1212, North Beach Manolis TSAPAKIS Institute of Marine Biofogy of Crete, GR-71003 Heraklion, POB 2254 & Nives KOVAČ & Alenka MALEJ Morska biološka postaja, Nacionalni inštitut za Biologijo, 51-6330 Piran, Fornače 4Î POVZETEK Analizirali smo izotopsko sestavo dušika v obrasti na umetnih substratih, lociranih v neposredni bližini ribjih farm in na neonesnaženih referenčnih lokacijah v severnem Jadranu (Piran, Slovenija), v vzhodnem Sredozemlju (Kreta, Grčija) in v Rdečem morju (Eilat, Izrael). Na dveh od treh lokacij smo izmerili povečano vsebnost 0!iN v organizmih ob ribjih farmah, kar je posledica vgrajevanja izotopsko težjega dušika iz suspendirane snovi, ki se sprošča v okolico iz ribjih kletk. Ključne besede: ribja farma, stabilni izotop, dušik, umetni substrat, organizmi obrasti REFERENCES Altabet, M. A-, C. Pilskaln, R. Thunell, C. Pride, D. Sig-man, F. Chavez & R. Francois (1999): The nitrogen isotope biogeochemistry of sinking particles from the margin of the Eastern North Pacific. Deep-Sea Res Part I, 46, 655-679. Mazzola, A. & G. Sara (2001): The effect of fish farming organic waste on food availability for bivalve molluscs (Gaeta Gulf, Central Tyrrhenian). Aquaculture, 192(2-4), 361-379. McGhie, T. K., C. M. Crawford, f. M. Mitchell & D-O'Brien (2000): The degradation of fish-cage waste during fallowing. Aquaculture, 187, 351-366. Minagawa, M. & E. Wada (1984): Stepwise enrichment of ,SN along food chains: Further evidence and the relation between 5,r'N and animal age. Geochim. Cosmo-chim. Acta, 48, 1135-1140. Montoya, }. P. (1994): Nitrogen isotope fractionation in .the modern ocean: implications for sedimentary records: in: Zahn, R., T. F. Pedersen, T. F. Kaminskt & L, Labeyrie (eds.): Carbon Cycling in Glacial Ocean: Constraints of the Ocean's Role in the Global Change. Springer, Berlin, 259-2.79. Nakatsuka, T., N. Handa, E. Wada & C. S. Wong (1992): The dynamic changes of stable isotopic ratios of carbon and nitrogen in suspended and sedimented particulate organic matter during a phytoplankton bloom. ). Mar. Res., 50, 267-296. Sigfeo, A. C. & S. A. Macko (1985): Stable isotope and amino acid composition of estuarine dissolved colloid material. In: Sigleo, A. C. & A. Hattori (eds.): Marine and estuarine geochemistry. Lewis publishers, Chelsea, USA, 29-45. Ye, L X., D. A. Ritz, G. E. Fenton & M. E. Lewis (1991): Tracing the influence on sediments of organic waste from a salmonid farm using stable isotope analysis, j. Exp. Mar. Biol. Ecol., 45, 161 -174. 12 ANNALES • Ser. hist. nat. -13 • 2003 • 1 - Supplement short scientific; article UDK 639.32:504.064(262:3-18) received: 2003-09-19 sedimentation and composition of particulate matter in a marine fish farm (gulf of trieste, northern adriatic); preliminary results Nives KOVAČ & Branko ČERMELJ National Institute of Biology, Marine Biology Station, SI-6330 Piran, Fornače <11 E-mail: kovac@mbss.org Sonja LOJEN "Jožef Stefan" Institute, Department of Environmental Sciences, SM 000 Ljubljana, Jamova 39 ABSTRACT Composition and sedimentation of particuiate matter was determined in a fish farm of the Slovenian coastal sea. The average sedimentation rates ofTPM, POC and TPN measured in the farm were higher than those on the control site due to food supply to fish and organic waste from fish farming activity. The impact of fish feeding was also evident from the isotopic (S'sN values) and elemental composition (C and N) of sedimented material with higher values in the fish farm area. Changes in composition of particulate matter and sedimentation fluxes were related to feeding regime during the year and seasonal characteristics of the water column. Key words: fish farming, elemental composition, S15N, sedimentation rate, northern Adriatic SEDiMENTAZÍONE E COMPOSiZIONE DI MATERIA PARTICELLATA IN UN AELEVAMENTO MARINO DI PESCI (GOLFO DI TRIESTE, ADRIATICO SETTENTRiONALE); RISULTATI PRELIMINAR! SINTESI La composizione e la sedimentazione della materia panicellata sono State determínate ad una profondith di oito metri in un allevamento di pesci in acque costiere della Slovenia. I tassi medí di sedimentazione di materia parti-cellata totale (TPM), carbónio orgánico particellato (POC) e azoto particellato totale (TPN) sono risultati maggiori di quelli rilevati nel sito di control lo, a causa del mangime per pesci. L'impatto del nutrimento di pese i é risu Itato evidente anche dalla composizione isotopíca (valori S'sN) ed elementare (C, N) del materiale sedimentato, con valori maggiori nell'area dell'allevamento ittico, Variazioni stagionali della materia particellata e flussi di sedimentazione sono stati correlati al regime alimentare durante Panno e alie caratteristiche stagionali della colonna d'acqua. Parole chiave; alíevamento di pesci, composizione di elementi, tasso di sedimentazione, Adriático settentrionale 13 ANNALES • Ser. hist. nal. • 13 - 2003 - 1 • Supplement Nívce KOVAČ ei i!.: 5 EDI MENTA T! ON AND COMPOS1TION OF ^ARTICULATE MATIER !N A MARINE FISH FARM (GUIE OF TRIESTE..... IM6 INTRODUCTION The northern Adriatic is an area under significant impact of fish farming activity, which influences the marine environment. Environmental impact is mostly caused by the supply of unconsummated food and fish feces (Har-grave et al., 1993) leading to high sedimentation rates and consequently to anoxic sediments and impoverishment of benthic fauna (Duplisea & Hargrave, 1996; Mazzola et al., 1999; Karakassis et al., 2000). The water quality is affected both by particulate and solute waste (Pitta et al., 1999), which can influence the phytoplank-ton growth (Frid & Mercer, 1989; Arzul etai, 1996). This work is part of a larger study (EU/BIOFAQs project) to investigate the efficiency of biofiIters as reducers of negative impacts of marine cage aquaculture. Our study has been carried out in 2001 to determine the seasonal changes in sedimentation fluxes and composition of particulate matter in the fish farm area in comparison to the selected control point. MATERIALS AND METHODS The investigated fish farm Lera d.o.o. is one of the two Slovenian farms situated in the coastal waters of Bay of Piran - Gulf of Trieste (northern Adriatic) (Malade & Forte, this volume). The fish (European Sea-bass) were fed commercial pelted fish food (Marico Start Premium). The food input increased from January to spring and with minor deviation at a high level during the summer, followed by a continual decrease until the following spring. Four arrays of bio-filters were moored along square cages at a distance of approximately 3 m, and this area was selected as a sampling site (Plate I: Fig. 1). On the horizontal array of bio-filters, cylindrical sediment traps with diameter of 7 cm and an aspect ratio of 7 were mounted at depth of 8 m (Fig. 1) to collect sinking particles. Sediment traps were designed to collect four samples simultaneously and were deployed for 24 hours. Similarly, the sedimentation rates were also measured on control site (CD including control arrays that were deployed approximately 150-200 m from cages in SE direction. During 2001, four samplings were carried out in july, August, September and November. After the collection, three aliquots of homogenized suspension from two cylinders at each locations were filtered through precombusted Whatman GF/F glass mi-cro-fibre filters. All samples were freeze-dried for 24 hours and weighed. Dried samples were used for analysis of total suspended matter (TSM), particulate organic carbon (POC), total particulate nitrogen (TPN) and iso-topic composition (,3C and 1SN). Total particulate matter was determined gravimetrically. Organic carbon (POC) and total particulate nitrogen (TPN) analyses of the freeze-dried and acid-washed samples (Hedges & Stern, Fig. 1: Scheme of biofi Iters arrays showing the deployment of sediment traps. SI. 1: Shematska predstavitev sistema umetnih substratov (biofiltrov) ter postavitev sedimeninih pasti. 1984) were performed with Carlo Erba elemental analyser 1108. Analyses of the 13C and ,SN isotopic composition of the freeze-dried samples were performed with a Etiropa 20-20 (Europa Scientific) mass spectrometer. Stable-isotope ratios were expressed in S notation as parts per mil (3M according to the following relationship: SX = [{Rsiimple/Rsaroferet) ~ 13 x ^ where X is 1 ?'C or f:,N and R is the corresponding ratio riOl2C or ,5N/UN. Standards for "C and ,SN are V-PDB and atmospheric N2 (air), respectively. RESULTS AND DISCUSSION The results of elemental composition of sedimented total particulate matter (TPM) from sampling (SL) and control (CD sites are presented in Table 1. In accordance with our expectations, the material collected in the traps deployed along the fish cages at a depth of 8 m had a higher portion of organic carbon (POC) and total particulate nitrogen (TPN) in comparison to the control site. This enrichment in organic carbon and total nitrogen of particulate matter of SL indicates a contribution of organic waste from partially degraded or uneaten fish food containing high content of organic carbon and nitrogen (Marico Start Premium: 44% C and 9% N). How- 14 ANNALES ■ Ser. hist. nat. • 13 • 2003 • 1 • Supplement Nires KOVAČ el at,: SEDIMENTATION AND COMPOSITION OF PARTICULATE MATTER (N A MARINE EiSH FARM (GULF OF TRIESTE ever, the differences between two sites were more evident during the summer samplings indicating more intense feeding regime of fish. Tab. 1: Average S'SN (%o) values and elemental composition of the sedimented particulate matter at sampling (SL) and control (CL) sites expresed as a percentage of total particulate matter (TPM), Tab. I: Povprečne vrednosti SUN (%,) in elementna sestava sedimentirane suspendirane snovi na vzorčišču (SL) in kontrolni postaji (CL), izražena kot odstotek celotne suspendirane snovi (TPM). j SEDIMENT TRAP SAMPLES 1 Sampling site (SL) Control site (CL) 1 /«/ Auf! Sep Nov Jul Au% Sep Nov POC (%) j 5.95 11.95 2.76 339 2.02 8.11 2.15 2.71 TPN {%} 0.71 1.39 0.38 0.5 i 0.31 1.1 S 0.31 0.43 C/N (at.) 9.96 10,05 8,36 7.74 7.63 8.08 8.05 7.34 S'SN*(%.)| 7,6 6.3 4.6 4.7 5.8 5.6 1.1 4.6 The average sedimentation rates of TPM, POC and TPN {Figs. 2, 3, 4) reveal higher values on station SL. The same trend, but with higher values, has already been reported for another Slovenian fish farm in the Gulf of Trieste using bottom traps (Kovac at al., 2001). This is in accordance with general observation that the quantity of trapped material increases with depth (Hargrave & Tagi.iC.hi, 1978). Sedimentation rates of particulate organic carbon determined in July, August, September and November in fish farm were by about 67%, 78%, 48% and 24% higher than those measured at control point. The same was observed for the sedimentation rates of TPN. However, greater differences between both sites during the summer probably result from a higher rate of food addition in this period. The 5I:,N average values of sedimented material at SL also indicated higher supply of fish food and feces during the summer (average 7.0%o) and greater impact of the sediment in the autumn (4.7%o). Comparison of 5°C of sedimented matter does not show significant differences, indicating that this parameter is not very suitable for this kind of study (KovaC eta!., 2.001). Additionally, the seasonal characteristics (physical, biological) of the water column influenced sedimentation and composition of particulate matter. The late autumn period was characterized by an increased significance of land material (fresh-water supply), resus-pension and grater mixing of water body, in the summer period, the greater stability of stratified water column with an impact of sedimented pbytoplankon material to sedimented matter was determined. Compared to data from control site,'where all meas-ured values were lower, the composition and sedimentation of particulate matter from fish farm highly reflects the impact of organic material from the fish farming activity (mostly fish food and waste). 40.00 35.00 30.00 25.00 20.00 15.00 10.00 5.00 0.00 JLn., u A- ^ ^ v1' >0 .<5S Fig. 2: Sedimentation rate of total particulate matter. SI. 2: Hitrost sedimentacije celotne suspendirane snovi. __ 100(100 800.00 c ai 600.00 -Ê 400.00 O 200.00 0.00 ......o,..........lu., / .2 500 -s y i may jufy sept nc»/ Deployment period Fig. I: Wef biomass of fouling organisms with deployment period, SI. 1: Biomasa organizmov obrasti v času postavitve biofiltrov. ANNALES • Ser. hist. nat. ■ 13 • 2003 ■ 1 ■ Supplement Eugenia APOSTOLAKI ČTiiTlrFECT OF TIMF OF FIRST DEPLOYMENT AND~DURATION ON THE SUCCESSION OF BENTHiC ORGANI^™:!/^-^ SO O) 40 —Q— may -¿-sept « (0 £t c E 3 a 5 c £ •> u ,Si TO 'u s o a. 30 20 - 0 -,------ may 20000 . 10000 ■ 5000 may in c ^ — X » « g -o i. c C — o >. c c « £ S m > 13 100 1 75 - Ol C o T: 25 Deployment period Fig. 2: (a) Species number; (b) tnacrofaunal abundance; (c) Shannon-Wiener diversity index; (d) average taxonomic distinctness with deployment period, SI. 2: (a) število vrst; (b) abundanca makrofavne; (c) Shannon-Wienerjev indeks diverzitete; (d) povprečna takso-nomska različnost glede na obdobje postavitve. !.: MAR ¡CULTURE-EN VI RON,VIE NT INTERACTIONS ANO BIOFUTRATION IN OLIGOTROPHY RED SEA WATERS. 33-36 INTRODUCTION Marine finfish aquaculture generally affects the underlying sediments as a result of the rain of particulate organic matter constantly failing to the seafloor, but it is generally more difficult to detect the dissolved effluents and their effects on the surrounding water column (Pearson & Black, 2001). The "elusive" nature of dissolved riLitrients emitted from fish cages is due to the fact that fish excrete riLitrients in a pulsed fashion (nutrients are excreted several hours after feed is ingested; Porter et ai, 1987) and these compounds are then subject to dilution, advection and biological uptake. Since it is much more difficult to accurately monitor nutrient release from fish cages in the sea, controlled tank experiments have been used to determine nutrient budgets for cultured fish and these indicate that intensively-reared carnivorous fish (as salmon and scabrearn) excrete considerable amounts of dissolved nutrients (70% and 35% of ingested N and P, respectively; Pearson & Black, 2001; Lupatsch & Kissil, 1998). There has been some debate regarding the actual effects of aquaculture effluent loading (both dissolved and particulate forms) on the marine environment and it appears that this may vary as a function of the trophic status of the surrounding waters. It is generally accepted, however, that the effluents released from fish cages should be minimized and we have examined the deployment of biofiIters around fish cages (the BlOFAQs project) to accomplish this. A factor that determines the success of such deployments is our ability to measure nutrient uptake by the experimental system in comparison to the reference. In other words, the proof (or failure) of the concept hinges on our ability to clearly separate a significant signal from the background noise. Fig. 1: Biofouiing community associated with one of the biofilter units at the fob-farm s/fe 6 months after deployment. SI. 1: Združba obrasti na biofi It ru ob ribogojnici šest mesecev po njihovi postavitvi. Fig. 2: Biofouiing community is virtually absent from the biofilter units at the reference site 6 months after deployment. St. 2: Domala neporasti biofilter na referenčni postaji šest mesecev po postavitvi. 34 ANNALES • Ser. hist. nat. - 13 • 2003 - 1 • Supplement Drot I. ANGFl si: MAR1CUI .TUBE-ENVIRONMENT INTERACTIONS ANO Btf lETl.TRATiON IN OUGOTROPHIC KEG SEA WATERS~JJ The Gulf of Aqaba, Red Sea, is an oligotrophia body of water that supports two commercial Israeli net-cage fish farms. These farms serve as point-sources of nutrients that are released to the surrounding waters and sediments. In an attempt to capture and remove effluents from the fish farm region, experimental biofilters were deployed and tested and the results of these deployments were compared to similar tests conducted at fish farms in 3 other countries: Scotland, Slovenia and Greece. MATERIALS AND METHODS The experimental design was identical (for comparative purposes) at 4 study sites in Scotland, Slovenia, Greece and Israel and consisted of deployment of arrays of cylindrical, plastic-mesh biofilters adjacent to the fish farm and at a reference site, 400 rn away from the farm. The biofilters were monitored and subsampled on a bimonthly basis to compare biofouiing biomass and community composition. RESULTS AND DISCUSSION The biofouiing biomass associated with the cylindrical biofilters at the fish farm site (Fig. 1) was much larger than the biomass at the reference site (Fig. 2), indicating that the fish-farm biofilter communities were growing more rapidly. We have proposed that this is due to lite larger food resources available at the fish farm. This preliminary conclusion relies mainly on the fact that the Gulf of Aqaba is oligotrophic (Reiss & Hottinger, 1984) and there are no other major nutrient sources in the re- gion, aside from the fish farm effluents.-At'other' BIO-FAQs study sites, there was not as clear a distinction between the biomass accumulation at the fish, farm site vs the reference site and it is assumed this is due, at least partially, to the distinctly different microenvironment that exists around the fish farm. In an accompanying study, Lojen ef a/, (2003, "this volume} examined stable isotope biomarkers to identify the source of material contributing to the biofilter biomass. The source was identified as particulate material released from the fish farm and taken up by the biofilter-associated biota. The interpretation of the data in this study was facilitated by the large signal to noise ratio due to the fact that the fish farm is a large, identifiable point source operating in an oligotrophic basin that has very few terrestrial or aeolic inputs. When compared to similar stable-isotope studies within the BIOFAQs project that were conducted in more productive waters with more "background noise" (large terrestrial inputs of organic and inorganic compounds, high algal and zoo-plankton biomass), it was much harder to determine if the biofilter communities near the fish cages were taking up fish farm effluents. There are many advantages to carrying out marine research in the Gulf of Aqaba and the presence of finfish farms in these unique, oligotrophic waters constitutes a large-scale, in-situ nutrient-enrichment experiment; not extremely dissimilar to the 1RONEX experiments currently going on in the Southern Ocean, with many opportunities to study aquaculture and nutrient impacts. OKOLjSKE INTERAKCIJE VMARIKULTURI IN BiOFILTRIRANJE V OLIGOTROFNIH VODAH RDEČEGA MORJA Dror L. ANGEL, Noa EDEN, Timor KATZ Israel Oceanographic & Limnologicai Research, Ltd., National Center for Mariculiure, Eilat, Israel e-mail dror@mil.edu & Ehud SPANIER The Leon Recanati Center for Maritime Studies, Haifa University, Haifa, Israel POVZETEK Avtorji so med eksperimentom, ki so ga opravili na Škotskem, v Sloveniji, Grčiji in Izraelu (v Rdečem morju), ob kletkah za gojenje rib in na bližnjih referenčnih lokacijah obesili vrsto luknjičavih plastičnih valjev. Namen eksperimenta je bil ugotovili,, ali se obrast, ki se je razvila na valjih v bližini marikulturnih kletk, močno razlikuje od referenčnih lokacij in ali je mogoče izmeriti pomenljivi privzem odpadnih voda. NajpomembnejŠe razlike v obrasti biofiltrov oh ribogojnicah in na referenčnih postajah so bile ugotovljene na izraelskih lokacijah, kar so avtorji pripisali znatno manjšemu vplivu drugih virov onesnaženja v oligotrofnih vodah Rdečega morja. Ključne besede: marikultura, biofiltri, obrast, oligotrofno morje, Rdeče morje 35 ANNALES ■ Ser. hist. nat. - 13 • 2003 • 1 - Supplement Deoi I. ANGE1 ei a/.; MARICULTURE-ENVIRQNMENT INTERACTIONS ANO E5IOFII.TSATION IN Oi St »TROPHIC RED SEA WATERS, 33-3G REFERENCES Lojen, S., D. Angel, T. Katz, M. Tsapakis, N. Kovač & Alenka Maiej (2003): 1SN enrichment in fouling communities influenced by organic waste deriving from fish farms. Annals Isfr. Medit. Stud. 13 (1) Suppi. 9-12. Lupatch, I, & G. W, Kissil, (1998): Predicting aquacul-ture waste from gilt.head seabream (Sparus aurata) culture using a nutritional approach. Aquat. Living Resour. 1 1, 265-268. Pearson, T. H. & K. D. Black, (2001): The environmental impacts of marine fish cage culture. In: Black, K. D. (ed.) Environmental Impacts of Aquacukure. Sheffield Academic Press, pp. 1-30. Porter C. B., Krom M. D., Robbins M. G., Brickell L. & A. Davidson (1987): Ammonia excretion and total n budget for gilthead seabream (Sparus-aurata) and its effect on water-quality conditions. Aquaculture 66: 287-297 Reiss, Z. & L, Hottinger, (1984): The Gulf Of Aqaba: Ecological Micropaleontology. Springer-Verlag, New-York. 36 ANNALES • Ser. hist. naí. ■ 13 • 2003 • 1 • Supplement short scientific article UDK 639.32:504.064(262,3-181 received: 2003-09-19 ■ ■ ' the influence of fish cage aquaculture on bacterioplankton in the bay of piran (gulf of trieste, adriatic sea) Valentina TURK & Alenka MALEI National Institute of Biology, Marine Biology Station Piran, SI-6330 Piran, Fomace 41 E-mail: (yrk@rnbss.org ABSTRACT The impact of fish cages on bacterioplankton was examined in enclosures containing seawater from cage and non-cage sites and natural plankton from the Bay of Piran (northern Adriatic). Nutrient enriched seawater stimulates bacterial production and abundance. This observation was further investigated in situ, where for 3 months submerged bio-filter with Schizobrachieila sanguínea dominating fouling community was enclosed in mesocosm. Based on the results of bacterial production and abundance, we assumed that filter feeding could remove significant amount of bacteria attached on suspended panicles and thus depleting bacterioplankton in the water column. Key words: aquaculture, environmental impact, bacterioplankton, cyanobacteria, Adriatic Sea INFLUENZA DELLA PISCICOLTURA IN GABBIE SUL BATTERIOPLANCTON NELLA BA1A DI PIRANO (GOLFO DI TRIESTE, MARE ADRIATICO) SINTESI L'impatto di un allevamento di pese i in gabbie sul batterioplancton e stato esaminato in contenitori da laboratorio contenenti acqua marina proveniente dall'allevamento, da un sito prossimo aii'allevamento e da una stazione di controllo con plancton naturale della bala di Pirano (Adriático settentrionale). L'acqua proveniente dall'allevamento di pe se i, arricchita in nutrienti, stímola la produzione e l'abbondanza batierica. Tale osservazione é stata successi■■ vamente investígala in situ con l'immersione pertre mesi di bio-filtri con una comunita di fouling con predominante Schizobracbieila sanguínea inclusa nel mesocosmo. In base ai risultati di produzione ed abbondanza batterica, gli autori concludono che Talimentazione di filt.ri puo rimuovere quantith significanti di batteri legati al particellato sospeso e quíndi diminuiré il batterioplancton nel la colorína d' acqua. Parole chiave: acquacoltura, ímpatto ambiéntale, batterioplancton, cianobatteri, mare Adriático 37 ANNALES ■ Ser. hist nat. • 13 • 2003 • 1 • Supplement VatBlililB TURK & Alenka MALCI: THE INFLUENCE Of FISH CAGE AQUACULTUKE ON BACTERlOPLANKTON IN THE BAY OF PIRAN .... 17-42 INTRODUCTION Bacteria play a central role in all major nutrient cycles in the marine environment (Azam, 1998). They are also most important organisms involved in different systems designed to treat domestic wastewaters. During the last few years, a series of papers was published addressing the impact of fish farming on water column chemistry and the effect on plankton distribution (Pitta et al., 1999; Alongi et ah, 2002). However, the role of bacteria in the environment impacted by the caged fish culture has received little attention. Bacterioplankton community and abundance in pelagic system can be regulated by bottom-up and top down regulating forces. The fish farming activity may have direct and indirect effects on the components of the microbial food web either by changing nutrient status of the environment or by altering prey and predator community composition. The present study is part of the EU funded project BlOFAQs (Bio-filtration and Aquaculture: an Evaluation of Hard Substrate Deployment Performance Within Mariculture Developments) (Angel, 2001; Black et a!., 2001). The main objective was to assess the effectiveness of deployment of artificial substrates (bio-filters) in the water column in reducing the environmental impacts of cage fish culture. By providing surface area for sessile biota and microbial colonization, bio-filters would facilitate uptake of organic and inorganic matter released by farmed fish. Within this project the microbial dynamics was followed in the enrichment experiment, using seawater from fish cage as nutrient source for enclosed plankton population, and seawater collected at unimpacted area. Additionally, microbial abundance and production was measured in mesocosm with enclosed bio-filters together with surrounding water during 2 die! cycles. MATERIAL AND METHODS Enrichment experiment was undertaken in July 2001 and lasted for 5 days (from 30(l1 July to 5th August). Seawater was collected with Niskin sampler in the middle of the fish cage (treatment C), at the station about 200 m from the cages (station CL, 5 m depth) (treatment B), and at the stations in the middle of the Bay of Piran (45°30.20; 13°34.20) (control - treatment A) (Plate I: Fig. 1). Seawater was filtered through 0.22 pm pore size filters (Millipore), poured into the transparent polyethylene bottles (Nalgen, 8 litres), and one litre of concentrated seawater with entire plankton community was added. Experimental plankton communities were collected above the thermocline layer (14 m depth) in the middle of the Bay of Piran. Enclosures were incubated in situ at a depth of 2 m, to provide natural temperature and light conditions. [NTEKFACC !■ ' -j ' / -U- .. 7 ^.Sv;:^-1 PC . . . •• .'1 I js FlVrsc.-Un ■■■■■ p MK'ROPROFfiJKR SAMPLING PIPE FOR DIEM! C A!. ANALYSES pt'll yf'] 3111 e\e' ■ a ■ / PERSPEX^,. CLAMPER ' \ 'I " ifrs'iH J ■ "ti (I '■-.v.. . - Fig. 1: Scheme of the mesocosm in situ enclosure experiment. SI. 1: Shema mezokozemskega eksperimenta v naravnem okolju. In situ enclosure (mesocosm) (Fig. 1) experiments were performed on the 3rd and 5rh months after bio-filters immersion into natural environment (Plate I: Fig. 1) at the station near fish cages (station SL), and at the station 200 rn from the cages (station CL) (Plate IS: Fig. 14). The mesocosm represented an in situ enclosure of selected bio-filter in natural environment. Each selected bio-filter was enclosed within a clear acrylic plastic octagon box, with a volume of about 110 litres (Fig. 1). A fine scale profiler with sensors (Sea Bird and Sea Tech) was connected to the chamber to measure, each hour, temperature, conductivity, dissolved oxygen and fluorescence. Divers collected samples for chemical and biological parameters from the chamber five times over 24 hours, from 26 to 27 September and 21 to 22 November at the station CL and at the station SL from 27 to 28 September 2001 and from 23 to 24 November 2001. At the same time intervals water column characteristics were performed using fine-scale profiler (CTD - University of Australia). The seawater for chemical and bio- 38 ANNALES • Ser. hist. nat. • 13 • 2003 • 1 • Supplement Val em in a TURK & Alenka MALE I : THE INFLUENCE OrllŠHCACE AQUACULTURE ON 8ACTERIQPLANKTON IN THE BAYOI: f'IKAN 37-42 logical parameters was collected at three different depths (5 m, 8 m, 11 m) using a membrane pump {flow rate 20 I per minute). Heterotrophic bacteria were counted according to the Porter and Feig protocol (Porter & Feig, 1980) and the biovoiume of bacteria was converted into carbon biomass using 20 fg C cell"' as the conversion factor (Lee & FLfhrman, 1987). Cyanobacteria were counted in green excitation using an epifluorescence microscope (Takahashi et al.r 1985). Bacterial production (BP) was measured by 3H-leucine incorporations according to procedures of Smith & Azam (1992). Each time, 1.7 ml of seawater was incubated with L-[4,5-3H] leucine {20 nM final, Amersham) for 1 hour at in situ temperature. All samples were done in triplicate. Bacterial production was calculated as in Simon & Azam (1989). At the same time, 3H-thymidine incorporation method was used in parallel samples (Fuhrman & Azam, 1982). Triplicates of each sample were incubated for one hour at in situ temperature with 250jjCi 3H-thymidine 1"' (sp. act. 80 Ci mmol""5, Amersham). Moles of thymidine incorporated were converted to cells produced by the conversion factor 2 x 10,s cells mole-1. RESULTS AND DISCUSSION An enrichment experiment was set up to examine the impact of fish farming on nutrients and microplank-ton distribution. During the five days of incubation, natural bacterioplankton community showed significant enhancement on production rates and biomass accumulation in the enclosures with the water from the fish cage (treatment C) and nearby station {treatment B), compared to the seawater from the non-impacted area (treatment A), Abundance of bacteria increased from 0.5 to 4.3 x 10s cells I'1 in the treatment B, from 0.6 to 3.8 x 106 cells I"1 in the treatment C three days after the inoculation {Fig. 2). The highest bacterial prodLiction was measured on the second day with the value of 2.02 pg C I'1 h"1 in the treatment B, compared to the production of I.01 pg C I'1 h"1 in the treatment C (Fig. 2). Cyanobacteria were more abundant tn the treatment with seawater from fish farm (treatment C) and increased from 3.3 to 7.8 x 10' cells I'1 in treatment B, and from 3.1 up to II.0 x 107 ceils I"1 in treatment C within four days of incubation, and only up to 2.8 x 107 cells l'! in the control bottle. Natural population of heterotrophic bacteria quickly responded to the nutrient enriched seawater, preceding autotrophic organisms, which was also reported in previous studies (Pitta eta!., 1996; Malej eta/., 2003). Fig. 2: The bacterial abundance (—) and production (□) in different nutrient treatments during the enrichment experiment lasting from 30"' July to 5"'August 2001. Si. 2: Gostota bakterij (—) in produkcija (□) v različnih hranilnih razmerah v obogatitvenem poizkusu v času od 30. julija do 5. avgusta 2001. 1,0 U S i I 1 a.s fEEifaViw Sun«i GL • Scpi ?oni i^.OO SOJ Tirai (hcnj<] 2 % I ï Fig. 3: Bacterial abundance and bacterial production in the water column during 24-hour cycle at the station near the fish cages (station SL) and the station 200m away from the cages (station CL) in September 2001. Si. 3: Gostota bakterij in bakterijska produkcija v vodnem stolpcu (5 m, 8 m, 11 m) na postaji blizu ribjih kletk (postaja SL) in na postaji, oddaljeni 200m od ribjih kfetk (postaja CL) 24-mesečnem ciklu v septembru 2001. 39 ANNALES ■ Ser. hist. nat. - 13 • 2003 • 1 • Supplement "" ■ vafentma TURK & Alenka malnj: THE inruhncc Or FISH CAGE AQUACIJUURC ON BACTERIOl'i anKTON ¡n THE BAY OF PIRAN ..., 37-47 Tab. 1: Average bacterial abundance, bacterial production (BP) and P/B ratio in the water column at the station near the fish cages (station SL) and the station located 200 m away (station CL) during 24-hour measurement from 26 to 28 September and from 27 to 29 November 2001. Tab. 1: Povprečne gostote bakterij, bakterijske produkcije (BP) in P/B razmerja v vodnem stolpcu na postaji blizu ribjih kletk (postaja SL) in na postaji, oddaljeni 200 m (postaja CL) v 24-urnih meritvah od 26. do 28. septembra in od 27. do 29. novembra 2001. Station CL SL SL/CL Date No. Average ±SD No. Average + SD % 26/28 September 2001 Abundance (cells l"!) 11 1.57 x 10'J 3.75 x 10s 11 1.49 x 109 4.57 x 10" 95 BP(3H-Thy) (pgC I 'd"') 15 3.78 1.63 15 3.97 1.86 105 BP (JH-Leu) (pgC r'd"1) 15 4.80 2.27 15 5.84 3.09 122 P/B (d'1) 11 0.178 11 0.247 27/29 November 2001 Abundance (cells I"1) 8 1.15 x 10s 1.29 x 103 8 1.10 x 10s 7.64 x 107 96 BP (3H-I.eu) (prC r5d"5) 15 3.55 0.66 15 3.92 1.43 110 P/B (d'1) 8 0.154 8 0.175 Based on laboratory results, we decided to examine the possible effect of fish farm on bacterioplankton dynamic in the field. During the study of diurnal dynamics, five samples at three different depths (5 m, 8 m and 11 m) were analysed for each station (Fig. 3). Vertical distribution of heterotrophic bacteria was similar at all sampled depths, and the abundance varied from 1.41 x 105 cells I"1 to 2.3 x 109 cells I"'. The bacterial production measured as 3H-leucine incorporation varied from 0.2 to 1.9 pg C !"V at the station CI. and from 0.2 to 1.1 pg C l"V at the station SL, with the highest values at 5m depth over the 24 hour experiment (Fig. 3). Comparison between both sampling locations is presented in Table 1, based on the results of bacterial abundance and production rates dtiring the 24-hour measurements in September and November. The average number of bacteria was 1.49 x 10? cells"1 (±3.8x 10 , n=11) at the station near the fish cages, compared to the average number of 1.57 x 109 cells-' (±4.6x 10s, n=11 ) at the station located 200 m away. Bacterial production measured as 1H-!eucine incorporation was 5.84 pg C I 'd"' (±3.1 pg C d'\ n=15) and 4.8 pg C l'1d'1 (±2.3 pg C l~' d~\ n-15) at the station SL and CL, respectively. Similar were resLilts of the bacterial production measured as 3FI-thymidine incorporation (Tab. 1). No difference between both stations was recorded in November. The average number of bacteria was 1.15 x 109 cells I"' at the station CL and 1.10 x 109 cells I'5 at the station SL. The bacterial production was 3.92 pg C i'V5 at the station SL and 3.55 pg C I'M"' at the station SL (Tab. 1). The P/B ratios for the heterotrophic bacteria were from 0.070 to 0.342 for the station CL and from 0.071 to 0.642 at the station SL. Although the average biomass of bacteria was higher at the station located 200 m away from the fish farm, bacterial production was higher (5-22%) at the station near the fish cages. However, the abundance and pro- duction rates were in the range reported for the Gulf of Trieste (Turk et al„ 2001), Similar results were reported from other areas in the Mediterranean (Pitta ef a!., 1999), when the plankton community structures and abundance were more dependent on seasonal environmental characteristics and locations than by the presence of fish farming. In contrast to the results in the water column that did not show a significant difference, the results obtained in the enclosures were different, thus eliminating currents and tides. In situ mesocosm experiments were performed in order to relate microbial dynamics to sessile biota on bio-filter. The experiment was performed in Fig. 4: Results of bacterial abundance and bacterial production in the mesocosm experiment at the station near the fish cages (station SL) and at the station location above 200 m away (station CL) during 24-hour cycle m September 2001. SI. 4: Gostota bakterij in bakterijska produkcija v mezokozemskem poizkusu na postaji blizu ribjih kletk (postaja SL) in na postaji, oddaljeni 200 m (postaja CL) v 24-urnem ciklu, septembra 2001. 40 ANNALES ■ Ser. hist. »at. ■ 13 • 2003 • 1 • Supplement V.iicwm.i TliRK & AlctiU MAI.fi: THE INFLUENCE OF FISH CACF AQUACULTUI« ON BACTLSIOPLANKTON IN THE BAY OF PÏRAN September using the bio-filter, submerged for 3 months near the fish cages at a depth of 5 m. Dominating fouling community on the enclosed bio-filter was bryozoan (Schizobracbiella sanguínea! (Frumen et a!., this volume). Over a diel cycle, bacterial numbers constantly decreased throughout the experiment from 2.2 x 109 cells I"1 to 1.1 x 109 cells at the station SL (Fig. 4). Contrary to bacterial abundance, production showed an increase from midnight and early morning up to 4.5 pg C I"' h"1 in the enclosure with bio-filter at the station near the fish farm (station SL). According to high bacterial production and constant decrease in number during the night, it is assumed that the majority of the bacteria produced were consumed, presumably due to grazing of sessile organisms on bio-filters. Studies on bryozoans feeding indicate that small naitu !<••* are piiiKba! rood source (Hudges, 2001). m- Our preliminary study did not reveal any'Lirge-scaie: eutrophication or significant differences between stations near the fish farm cages and open water stations. However, a pronounced response of bacterial commit-' nity was observed after addition of enriched water from the fish farm in laboratory experiment and for in situ mesocosm experiment Results from mesocosm experiment showed that filter feeding could remove significant amount of attached bacteria on suspended particles and thus deplete bacterioplankton in the water column. However, bacteria within the pelagic ecosystem recycle the excreted nutrients and additional investigations should be considered in the future. VPLIV MARiKULTURE NA 8AKTERIOPLANKTON V PIRANSKEM ZALIVU Valentina TURK & Alenka MALE! Nacionalni inštitut za biologijo, Morska biološka postaja, SI-6330 Piran, Fornače 41 E-mail: turk@mbss.org POVZETEK Avtorici sta preučevali vpliv gojenja rib v kletkah na bakterioplankton v morski vodi z naravnim plnaktonom, vzeti z lokacij s kletkami in 200 m od njih v Piranskem zalivu. S hranilnimi snovmi obogatena morska voda spodbuja produkcijo in gostoto bakterij. Raziskave sta opravili tudi v naravnem okolju, v katerem je bil za 3 mesece potopljeni biofilter s prevladujočo vrsto Schizobrachiella sanguinea obdan z mezokozmom. Glede na rezultate produkcije in gostote bakterij avtorici domnevata, da bi filtratorski organizmi s hranjenjem lahko odstranili precejšnjo količino bakterij na suspendiranih delcih in tako zmanjšajo vlogo bakteriopianktona v vodnem stolpcu. KijuČne besede: inari kultura, okoljski vplivi, bakterioplankton, cianobakterije, jadransko morje REFERENCES Atong'i, D. M., V. C. Chong, P. Dixon, A. Sasekutrtar & F. Ttrendt (2002): The influence of fish cage aquaculture on pelagic carbon flow and water chemistry in tidaiiy dominated mangrove estuaries of peninsular Malaysia. Mar. Environ. Res., 55, 313-333. Angel, D. (2001): A review of biofiltration processes as used in waste management, in: A review of the environmental impacts of marine cage aquaculture, processes of biofiltration relevant to impact mitigation, the biological properties of marine invertebrates relevant to biofiltration and biofouling on artificial structures. BIO-FAQs Ann. Rep., Techn. Annex, p. 31-45. Arzul, G., C. A. Clement & A. Pinier (1996): Effects on phytoplankton growth of dissolved substances produced by fish farming. Aquat. Living Resour., 9, 95-102. Azam, F. (1998): Microbial control of oceanic carbon flux: The plot thickens. Science, 280, 694-696. Black, K. D., M. D. J. Sayer, E. Cook, D. Angel, E. Spanier, i. Karakasis, A. Malej, K. Collins, H. Pickering, S. Whrtmarsh & S. Lojen (2001): BIOFAQs - Biofiltration and Aquaculture: an evaluation of substrate deployment performance with mariculture developments. Cahier Options Mediterranneennes, 55, 205-207. Frumen, A., B. Vriser & A. Malej (2003): Suspended biofilters: succession of fouling communities immediately adjacent to fish cage and control location. Anna-les, Ser. hist, nat, 11(1), Suppl. Fuhrman, J, & F. Azam (1982); Thymidine incorporation as a measure of heterotrophic bacterioplankton production in marine surface waters: evaluation and field results. Mar. Biol., 66, 109-120. 41 ANNALES • Ser. hist. nat. -13- 2003 • 1 • Supplement Vslemma TURK & Aieilks MAIEJ: THE INFLUENCE OF EI5H CAGE AQUACUETURE ON BACTERIOPLANKTON IN THE SAY OF PIRAN ..., 37-12 Hughes, D. (2001): A review of biological filtration by marine invertebrates. In: A review of the environmental impacts of marine cage aquaculture, processes of biofil-tration relevant to impact mitigation, the biological properties of marine invertebrates relevant to biofi I tration and biofouling on artificial structures. BlOFAQs Ann. Rep., Techn. Annex, p. 49-77. Lee, S. & J. A. Fuhrman (1987): Relationships between biovolume and biomass of naturally derived marine bacterioplankton. Appl. Environ. Microbiol., S3, 1298-1303. Malej, A., P. Mozetic, V. Turk, S. Terzic, M. Ahei & C. Cauwet (2003): Changes in particulate and dissolved organic matter in nutrient-enriched enclosures from an area influenced by mucilage: the northern Adriatic Sea. j. Plankton Res., 25, 949-966. Pitta, P., L Karakassis, M. Tsapakis & S. Zivanovic (1999): Natural vs. mariculture induced variability in nutrients and plankton in the eastern Mediterranean. Hydrobiologia, 391, 181-194. Porter, K. G. & Y. S. Feig (1980): The use of DAP I for identifying and counting aquatic microflora. Limnol. Oceanogr., 25, 943-948 . Simon, M. & F. Azam (1989): Protein content and protein synthesis rates of planktonic marine bacteria. Mar. Ecol. Prog. Ser., 51, 201-213. Smith, D. C. & F. Azam (1992): A simple, economical method for measuring bacterial protein synthesis rates in seawter using 3H-leucine. Mar. Microb. Pood Webs, 6, 107-114. Takahashi, M,, K. Kikuchi & Y. Hara (1985): importance of picocyanobacteria biomass (unicellular, blue-green algae) in the phytoplankton population of the coastal waters of japan. Mar. Biol., 89, 63-69. Turk, V., P. Mozetic & A. Malej (2001): Seasonal variability in phytoplankton and bacterioplankton distribution in the semi-enclosed temperate gulf (Gulf of Trieste, Adriatic Sea). Annales, Ser. hist, nat., 11 (1), 53-64. 42 ANNALES • Ser. hist. nat. • 13 • 2003 ■ 1 • Supplement short scientific article UDK 504.064:574.6(26) received: 5. 09. 2003 biofilter community oxygen consumption rates Ken COLLINS & jenny MALUNSON School oS Ocean arsci Earth Science, University of Southampton, Southampton Oceanography Centre, Southampton SOH 3ZH, UK e-mail: kjc@soc.soton.ac.uk ABSTRACT Biofilter communities have been incubated in-situ in UK, Israel and Slovenia. Oxygen fluxes for light and dark experiments have been normalised using the ash free dry weight of the biota. Respiration rates for different communities, whether dominated by ascidians, hydroids, worms or sponges, show a remarkably consistent trend with temperature, over the range 6-2/'C. !t is planned to link respiration to rates of growth, filtering and nutrient release. Key words: community respiration, in-situ incubation, ascidians, hydroids, tube worms TASSI Di CONSUMO Dl OSSIGENO IN COMUNITA Dl BIOFILTRI SINTESI Git autori hanno stud into la crescita sovrabbondante di comunita di biofiltri in-situ in Regno Unito, Israele e Slovenia. I risu I tati dei flussl dl ossigeno in esperimenti di luce e buio sono stati normalizzati in base al peso secco pri-vo dl cenere del biota. A prescindere dal la composizione delte comunita, dominate a turno da ascidiacei, idrozoi, policheti sedentari o spugne, i tassi respiratori hanno evidenziato una tendenza notevolmente uniforme con temperature nell'intervallo tra i 6 ed i 27°C. Gii autori intendono correlare i risultati delle misurazioni della respirazione con i tassi di crescita e filtrazione degli organismi ed il rilascio di nutrienti. Parole chiave: respirazione di comunita, incubazione in-situ, ascidiacei, idrozoi, policheti sedentari 43 ANNALES • Ser. hist. nat. • 13 • 2003 • 1 - Supplement Ken COLLINS & Jenny MALL IN SON: BSORLTflt COMMUNITY OXYGEN CONSUMPTION RATES. 4J-46 INTRODUCTION MATERIALS & METHODS Ecological modelling of systems requires knowledge of the rates of energy flow. Thus, as well as the biomass in a system, its rate of growth or turnover should be determined. The growth rate of reef epibiota rate could be determined by measuring change in biomass per unit-area, with time. This is likely to underestimate the true growth rate since this cannot account for loss by preda-t.ion or other means. For a number of benthic infauna species the annual production per unit biomass has been calculated (Schwinghamer ef a/., 1986). This approach has been widely adopted for determining the productivity and energy flows through benthic systems. However for many of the groups, which grow on hard SLibstrates including artificial reefs (bryozoans, hydroids, sponges and ascidians) there is little or no information on their production to biomass ratios. Enclosed chamber (respirometer) experiments have a long history in examining the respiratory exchange and thus the energy utilization of animals (Collins et a/., 2002). The BIO-FAQs programme (Black ef a/., 2001; plus other papers in this volume) has deployed experimental biofiIters next to fish farms in order to determine the potential for the colonizing biota to remove wastes (particLilate organic carbon and nutrients) from the water cokimn downstream of the aquaculture facilities. This paper describes the resLilts of in-situ incubation chamber experiments to determine direct measurement of oxygen fluxes (and thus carbon fluxes) of biofi iter epibiota. ene way inlet value SIDE ELEVATIQM Fig.1: Diagram of the biofHter mcubation chamber. Fig. 1: Shema biofiitrske inkubacijske posode. The biofi iter incubation apparatus (Fig. 1) consisted of a specially constructed clear acrylic box (35 x 35 cm cross section, 65 cm high) which accommodated a whole biofi Iter, (a plastic mesh cylinder 50 cm long x 25 cm diameter) transferred underwater by divers. The top lid with neoprene sea! was clamped shut with over-centre clips. An internal water pump (Rule, USA, bilge pump, 12 V, 380 min"') was used to continuously mix the water in the chamber. A similar second pump was used to sample the chamber (30-40 min intervals) pumping water to the surface through 3 mm ID polythene tubing. The chamber water samples (160 nil, 3 replicates) were fixed for subsequent Winkler titration, to accurately measure the oxygen concentration. An oxygen electrode (YSi, model 5239) was used to monitor the progress of the incubation. Further Winkler titration bottles filled with water pumped from the chamber at the beginning of the experiment, were incubated in-situ under dark and light, to provide blanks, giving the magnitude of water column respiration and net photosynthesis respectively. Typically the chamber was incubated in the light for 2 hours then a further 2 hours in the dark, enclosed in a heavy-duty black polythene bag. This was considered to be a sufficiently short enough time to discount bacterial activity on the surface as of the chamber and not to cause starvation of the suspension feeders. Records of light intensity and temperature during the experiment and longer term enable extrapolation of the results of experiments over the whole year. At the end of the incubation the biofilter was recovered and the epibiota removed, sorted into taxonornlc groups and dried in aluminum foil trays to constant weight at 80°C. The dry samples were heated in a muffle furnace to 550°C for 4 hours to determine the organic content, ash free dry weight (AFDW). AFDW was used in this study as it was considered to be a good measure of the amount of living substance (Crisp, 1984), This is especially true given the number of calcareous organisms: hydroids, bryozoans and serpulid worm tubes that were present on the biofilters. Oxygen analysis was done by a modification of the manual Winkler titration (Strickland & Parsons, 1968). Fixed samples were acidified with concentrated sulphuric acid and titrated with sodium thiosulphate solution in the sample bottle with an automated burette and photo-detector system to monitor the end point (Williams and jenkinson, 1982). This system gave a repeatability of measurement in the order of ±0.2%. RESULTS AND DISCUSSION Bio-filter cylinders were deployed in July 2000, 2001 and 2002, 3 m below a pontoon in the Southampton Oceanography Centre dock and incubated at different 44 ANNALES • Ser. hist. nat. -13- 2003 • 1 ■ Supplement Ken COLLINS & Jenny MALUNSON: BIOFtLTER COMMUNITY OXYGEN CONSUMPTION RA VES, Tab. 1: Oxygen consumption rates for certain bentbic invertebrates (®mol02 gAFDW' hi'1). Tab. 1: Poraba kisika (mo!Oi gAFDW' hr"1) source Pyura sto to ni fera Ascidiacea 33 (Klummp, 1984) Styella plicata Ascidiacea 66 (Klummp, 1984) C ion a intestinalis Ascidiacea 47 (Klummp, 1984) Aglaophenia sp. Hydro idea 75 (Gili & Hughes, 1995) Eudendrium racemosum Hydro idea 72 (Gill & Hughes, 1995) times of the year to determine the response to temperature. These were originally intended simply to provide material for testing oxygen incubation chambers and refining the techniques. Prolific growth of the ascidian, Ascidiella aspersa, dominated the fouling community, reaching massive densities (27 kg wet weight per biofii-ter after 9 months) (Plate II, Fig. 11). A similar pattern of ascidian dominance and mass was found on the Scottish biofilters deployed at 12 m off Oban, Scotland, /n-situ incubation experiments were conducted here in September 2002. The comparability of the two sites may be explained by the fact that they are both in temperate waters and receive high levels of organic particulates, from the adjacent fish farm in Scotland and from effluent discharges into the estuary in Southampton. The fast growth of ascidians which have high filtration rates suggests potential for significant removal of particulate effluents in temperate seas. In May 2003 iri-situ incubation experiments at 5 m were carried out off Piran, Slovenia (Plate II, fig. 14). These biofilters were dominated by calcareous tube worms (Pomatoceros sp.). Since all three sites were fauna dominated, only the respiration rates are reported The rate of change in incubation chamber oxygen concentration with time was determined by linear regression (typically with an r2 >0.95). After allowing for the water column blank, the values were related to the AFDW of the biofilter. Figure 2 shows this biofilter oxygen consumption data compared to that obtained from the Poole Bay, UK artificial reef. (Collins et at., 2002). In the latter case whole colonized concrete reef blocks (20 x 20 x 40 cm) were incubated in-situ at 12 rn. These were dominated by hydroids (Haiecium spp.), bryozoans (Bugula piumosa) and calcareous tube worms (Pomatoceros sp.). One of the Southampton biofilters (20°C) was dominated by the fan worm Sabeita pavonina. Schwinghamer ei al. (1986) demonstrate that pro-duction/biomass and other biological processes including respiration depend on size class. The biofilters and artificial reefs communities are dominated by macro fauna of sizes within 1-2 orders of magnitude, which may explain both the correspondence and variation in the data. Temperature °C Fig. 2: Oxygen consumption by different communities plotted against incubation femperafi/re; experimental biofilters from Southampton, Oban and Piran and concrete artificial reef blocks from Poole Bay (Collins et al., 2002), showing a linear regression line with 95% confidence intervals. Fig. 2: Poraba kisika pri različnih združbah v korelaciji z inkubacijsko temperaturo: poskusni biofiltri iz South-amptna, Obana in Pirana in betonski umetni podvodni grebeni iz Poole Bay (Collins et al., 2002) so premočrtno povezani (linearna regresija z 95% intervalom zaupanja). Knowledge of instantaneous respiration rate of the biofilter community provides direct information on carbon and indirectly nitrogen and phosphorous fluxes. Current work is determining the nutrient release associated with biofilter community respiration. This will be combined with data from the other groups within the BIOFAQs project. Part of the energy derived from is devoted to growth (production). Published produc-tion/biomass ratios (Klumpp, 1984; Schwinghamer et al., 1986; Petersen et al., 1995) vary greatly, for the biofilter organisms values are in the range 10-40%. Comparison with known biofilter mass accumulation rates will help set limits to this. The filtration rates of biofilter organisms have been reviewed within the BIOFAQs 45 ANNALES • Ser. hist. nat. • 13 ■ 2003 • 1 • Supplement Ken COLLINS & Jenny MA LUN S ON: 81 OF i LTE R COMMUNITY OXYGEN CONSUMPTION KATES, «-<6 programme. For some organisms there is published information on the relationship of filtering rate to oxygen consumption: the ascidians Pyura stolonifera (Klumpp, 1984) and Ciona intestinal is {Petersen et al., 1995). As with production it is hoped to partition part of the energy to filtration to derive a simple model of the functioning of biofilters for aquaculture or in a wider context the ability of hard substrate (natural or artificial) com-munities in coastal waters to remove particulate matter from the water column. ACKNOWLEDGEMENTS This work was supported by the El.J funded BIOFAQs project. Incubation experiments were carried out at Southampton with the assistance of james Wyles, Elizabeth Vancura and Claire Lloyd. Considerable practical help with field work was given by many colleagues in Dunstaffnage Marine Laboratory, Oban and Marine Biological Station, Piran. PORABA KISIKA NA BIOFILTRIH Ken COLLINS & Jenny MALL INSON School of Ocean and Earth Science, University of Southampton, Southampton Oceanography Centre, Southampton 5014 3ZH, UK e-mail: kjc@soc.soton.ac.uk POVZETEK V Veliki Britaniji, Izraelu in Sloveniji sta avtorja spremljala proces obraščanja biofiltrskih združb in situ. Rezultati meritev kisika v svetlih in temnih razmerah so bili normalizirani na enoto organskega deleža biomase obrasti. Ne glede na sestavo združb in prevlado različnih skupin nevretenčarjev {kozolnjaki, trdoživnjaki, mnogoščetinci ali spužve) so rezultati respirometrije pokazali izredno enakomeren trend povezave s temperaturo v razponu med 6 in 27"C. Avtorja nameravata povezati rezultate respiracijskih meritev s stopnjo rasti filtratorjev in sproščanja hranil. Ključne besede: respiracija združbe, inkubacija in situ, kozolnjaki, trdoživnjaki, cevkasti mnogoščetinci REFERENCES Black, K. D., Sayer, M. D. Jv Cook, E,, Angel, Dv Spanier, E. Karakassis, I,, Malej, A., Collins, K., Pickering, H., Whitmarsh, D. and lojen, S. (2001): BIOFAQs -BlOfiltration and Aquaculture: an evaluation of substrate deployment performance with mariculture developments. Cahiers Options Méditerranéennes, 55: 205-207. Collins, K.J, Jensen, A.C. and Smith, I. P. (2002): Oxygen fluxes of enclosed reef epibiota communities. ICES journal of Marine Science 59: S94-S99. Crisp, D. J. (1984): Energy flow measurements. In: Holme, N. A. and Mclntyre, A. D. (eds.) Methods for the Study of the Marine Benthos. IBP Handbook No. 16, 2"d ed. Blackwell Scientific Publications, Oxford, pp. 284-373. Gili, J-M and Hughes, R. G. (1995): The ecology of marine benthic hydroids. Oceanography and Marine Biology: an Annula Review 33: 351-426. Grodzitiski, Wv Klekowski, R. 1. and Duncan, A. (1975): Methods for Ecological Bioenergetics. IBP Handbook No. 24. Biackwell Scientific Publications, Oxford, 367pp. Klumpp, D. W. (1984): Nutrional ecology of the as-cidian, Pyura stolonifera: Influence of body size, food quantity and quality on filter feeding, respiration, assimilation efficiency and energy balance. Marine Ecology Progress Series 19(3): 269-284. Petersen, J. K., Schou, O. and Thor, P. (1995); Growth and energetics in the ascidian Ciona intestinalis. Marine Ecology Progress Series 120(1-3): 175-184. Schwinghamer, P., Hargrave, B., Peer, D. and Hawkins, C, M. (1986): Partitioning of production and respiration among size groups of organisms in an intertidal benthic community. Marine Ecology Progress Series 31: 131-142. Williams, P. j. leB. and Jenkinson, N. (1982): A transportable microprocessor controlled precise Winkler titration suitable for field station and shipboard use. Limnology and Oceanography, 27: 576-582. 46 1 I PLATES / TABLE ANNALES • Ser. hist. nat. • 13 • 2003 • 1 ■ Supplement PLATES/ TABLE PLATE I/TABLA I Fig. 1: Fish farm in the Bay of Piran, Slovenia, showing positions of bio-filter arrays near fish cages (SL) and at location CL. SI. 7: Ribogojnica v Piranskem zalivu in postavitev nizov biofiltrov ob ribjih kletkah ter na lokaciji CL. Fig. 2: Schematic presentation of one array showing position of bio-filters; four such arrays were deployed along fish cages and four at location CL. Slika 2: Skica enega niza, ki kaže pozicijo biofiltrov; po štirje taki nizi so bili postavljeni vzdolž ribjih kletk in na lokaciji CL. Fig. 3: Underwater slide of bio-filter array at Crete. Slika 3: Podvodni posnetek niza biofiltrov na Kreti. Figs. 4-6: Comparison of fouling communities developed on bio-filters near fish cages (a) and control locations (b) in Scotland (4 a,b, after one month of immersion), Israel (5a, b) and Slovenia (6a, b, after one month of immersion) Slike 4-6: Primerjava združb obrasti na lokacijah v bližini ribjih kletk (a) in na kontrolnih lokacijah (b) na Škotskem (4a, b, en mesec po postavitvi biofiltrov), Izraelu (5a, b) in Sloveniji (6a, b, en mesec po postavitvi biofiltrov). 48 ANNALES ■ Ser. hist. nat. • 13 ■ 2003 • 1 ■ Supplement 49 ANNALES • Ser. hist. nat. • 13 • 2003 • 1 • Supplement PLATES / TABLE PLATE II / TABLA II Fig. 7: A variety of organisms on a bio-filter in site FF in Eilat (Israel, Red Sea): A tubular sponge, Siphonochalina sp.; a sea urchin Diadema sestosum; red sponges Mycale fistulifera; Salmacina sp. & losephella marenzelleri poly-chaets. SI. 7: Na biofiltre na postaji FF v Eilatu (Rdeče morje, Izrael) se je naselila množica sesilnih organizmov: cevasta spužva Siphonochalina sp.; morski ježek Diadema sestosum; rdeča spužva Mycale fistulifera; cevkasti mnoščetinci Salmacina sp. in Josephella marenzelleri. Fig. 8. Some stony coral Stylophora pistilata were also found among the epi-biota community on biofilters on both studied sites in Eilat (Red Sea). SI. 8: V združbi obrasti na biofiltrih na rdečemorskih postajah v Eilatu so se naselile tudi kamene korale Stylophora pistilata. Fig. 9: A mussel line in Eilat (Red Sea) was completely overgrown with the red alga Jania adhaerens and a variety of sessile invertebrates such as red sponges Mycale fistulifera, encrusting bryozoans Celleporaria aperta and hydro-zoans Thyroscyphus fruticosus. SI. 9: Vrv za školjke v Eilatu (Rdeče morje) je bila popolnoma obrasla z rdečo algo jania adhaerens in množico sesilnih nevretenčarjev kot so rdeča spužva Mycale fistulifera, skorjasti mahovnjaki Celleporaria aperta in trdoživnjaki Thyroscyphus fruticosus. Fig. 10: Underwater photo of the biofilter array in oligotrophic Mediterranean waters (Crete, Greece). Slika 10: Podvodni posnetek niza biofiltrov v oligotrofnih sredozemskih vodah (Kreta, Grčija). Fig. 11: The significant increase in biomass, particularly in the first 4 months after deployment was primarily due to an increase in the biomass of the ascidian, Ascidiella aspersa, at both studies sites off West Scotland. SI. 11: Plaščar Ascidiella aspersa je največ prispeval k znatnem porastu biomase na obeh postajah ob zahodni Škotski, še posebej v prvih štirih mesecih po postavitvi biofiltrov. Fig. 12: The rapidly colonising epibiota community on the biofilters at the Piran station (Slovenia) provided a variety of shelters for different fish species such as Symphodus tinea. SI. 12: Združba obrasti, ki se hitro naseli na biofiltrih, nudi številne niše za različne vrste niš, med drugim tudi za ustnačo Symphodus tinea. Fig. 13: Plaščar Polycarpa pomaria colonized biofilters at the station near fish farm in the Bay of Piran (Slovenia). SI. 13: The ascidian Polycarpa pomaria se je naselil na biofiltre na postaji ob ribogojnici v Piranskem zalivu (Slovenija). Fig. 14: Underwater photo of the biofilter incubation chambers (mesocosm) in the Bay of Piran, Slovenia (see Fig. 1 in Turk & Malej, this volume, for schematic presentation of experimental system). SI. 14: Podvodni posnetek inkubacijskih posod v Piranskem zalivu, Slovenija (Shema poskusnega sistema je predstavljena na sliki 1, v prispevku Turk & Malej, ta volumen). 50 ANNALES • Ser. hist. nat. • 13 • 2003 ■ 1 • Supplement PLATES / TABLE 51