NEW DATA ON THE DOLINES OF VELEBIT MOUNTAIN: AN EVALUATION OF THEIR SEDIMENTARY ARCHIVE POTENTIAL IN THE RECONSTRUCTION OF LANDSCAPE EVOLUTION NOVI PODATKI Z VRTAč VELEBITA: VREDNOTENJE USEDLINSKIH ARHIVSKIH MOŽNOSTI ZA REKONSTRUKCIJO RAZVOJA POVRŠJA Christele BALLUT1 & Sanja FAIVRE2* Abstract UDC 551.435.82(497.5) Christele Ballut & Sanja Faivre: New data on the dolines of Velebit Mountain: An evaluation of their sedimentary archive potential in the reconstruction of landscape evolution The first approach to the relationships between societies and physical environments on Velebit Mountain shows narrow correlations between spatial distribution of dolines, soil formation, hydric resources, vegetation and land occupation. In 2002, sediment cores have been obtained from different dolines of Velebit Mountain to evaluate the potential of their sedimentary archives in order to reconstruct the landscape history. On the littoral slopes and on the top parts of the mountain, the dolines were difficult to dig due to the presence of rocks in depth. Nevertheless, the cores have been sampled and soil analyses have been made (physical and chemical analyses: colour, grain size, pH, CaCO3, C, N, P, K, Mg, CEC). No dating materials were found. The first results attest to rather homogeneous pedo-logic processes in each area studied (Kamenica, Stinica, Baške Oštarije and Bilensko Mirevo), but they also indicate colluvial contributions. These contributions differ from one doline to another according to their location and morphology. Dolines reveal themselves to be not very good traps, as the representative nature of their sedimentary archives could be very local. However, the best profile has been obtained at Bilensko Mirevo, which shows a change in the soil nutrient content from an impoverishment in its middle part toward an increase of the soil nutrients in recent parts. Those environmental changes could not be precisely dated, but could be correlated with the 17'h to 20th century phase of strong human impact on the Velebit environment and with the rural depopulation observed since the second half of the 20'h century. Keywords: karst, dolines, Mediterranean soils, Velebit Mountain, Dinarides, Croatia. Izvleček UDK 551.435.82(497.5) Christele Ballut & Sanja Faivre: Novi podatki z vrtač Velebita: Vrednotenje usedlinskih arhivskih možnosti za rekonstrukcijo razvoja površja Prvi pristop k razmerjem med družbo in naravnim okoljem na Velebitu kaže ozko korelacijo med prostorsko razporeditvijo vrtač, tvorbo prsti, vodnih virov, vegetacijo ter rabo tal. Leta 2002 so bila iz različnih vrtač Velebita vzeta jedra sedi-menta, da bi ovrednotili možnosti usedlinskih arhivov za rekonstrukcijo razvoja površja. Na obmorskih pobočjih in na zgornjih območjih gorovja je bilo v vrtače težko kopati, saj so bila njihova dna zapolnjena s skalami. Vseeno so bila jedra izkopana in analize prsti narejene (fizikalne in kemične analize: barva, velikost zrn, pH, CaCO3, C, N, P, K, Mg, CEC). Najdenega ni bilo nobenega gradiva za datiranje. Prvi rezultati potrjujejo razmeroma homogene pedološke procese v posameznih proučevanih območjih (Kamenica, Stinica, Baške Oštarije in Bilensko Mirevo), kažejo pa tudi na vpliv koluvial-nih procesov. Ti vplivi se sicer razlikujejo med vrtačami glede na njihovo lokacijo in morfologijo. Vrtače se niso izkazale za dobro izbiro, ker je lahko reprezentativna narava usedlinskih arhivov precej lokalna. Najboljši profil je bil narejen pri Bilen-skem Mirevem, ki kaže spremembo v vsebini nutrientov v prsti od osiromašenih prsti v sredinskem delu profila do porasta nutrientov v prsti v recentnih plasteh. Teh okoljskih sprememb se ne da natančno datirati, vendar se jih da povezati z obdobjem večjega človekovega vpliva na Velebitu med 17. in 20. stoletjem in z ruralno depopulacijo koncem druge polovice 20. stoletja. Ključne besede: kras, vrtače, sredozemske prsti, Velebit, Di-naridi, Hrvaška. 1 ArScAn, UMR 7041-CNRS, 21 allee de l'Universite, 92 023 Nanterre, France, e-mail: christele.ballut@mae.u-paris10.fr 2* Department of Geography, Faculty of Science, University of Zagreb, Marulicev trg 19/II, 10000 Zagreb, Croatia, e-mail: sfaivre@geog.pmf.hr Received/Prejeto: 10.3.2011 ACTA CARSOLOGICA 41/1, 59-74, POSTOJNA 2012 INTRODUCTION According to its climatic, vegetation, pedologic and ecological properties, Velebit is a typical Mediterranean mountain. It is formed in carbonates which have provided predisposition for the development of rich karstic relief. Owing to the lithological and structural differences, different human impacts, but also due to different climatologic conditions that interchange from colder to warmer periods, the Mediterranean mountains have experienced diverse evolutions (Salomon 2000). As the soil in karst is sparse it can be found principally in karst depressions like dolines, uvalas and poljes, which represent traps for sediments. The most numerous such forms on Velebit Mt. are the dolines. They are karst landforms that are not only a result of karst dissolution, but also derive from other processes: pedogenetic processes, weathering, collapse, alluvial, aeolian, periglacial processes (Sauro 2003, 2004; Meneghel & Sauro 2006), and also from glacial processes on Velebit Mt. (Bognar et al. 1991; Bognar & Faivre 2006). Consequently, in many cases the sediment content at the bottom of the doline more or less masks the rock form. The study of the Velebit Mt. dolines has started with the analyses of their main morphological properties (Faivre 1992, 1994), where the doline disposition, shape and size were related to the structural properties of the area. Furthermore, we have attempted to establish the connection between spatial distribution of dolines and recent deformations (Faivre & Bocquet 1999; Faivre & Reiffsteck 1999a, 1999b, 2002; Faivre 2000; Faivre & Pahernik 2007). The doline fills (soil) study, which was started in 2002, is a logical continuation of this work. From prehistoric times, Velebit has been a mountain with a pastoral economy and the dolines (karst de- pressions) have been used for agrarian activity (Faber 1984, 1995a; Faber 2000). Therefore, we have tried in this work to estimate the potential of the sedimentary archives of Velebit Mt., localised in the dolines, seeking to reconstruct a longer socio-environmental history by relating geomorphological, climatic, pedological and environmental conditions. The studies of soils in the dolines have been conducted by numerous authors (e.g. Lovrenčak 1977; Bara-ny 1980; Magaldi & Sauro 1982; Bayonnette 1998; Hoyk 1999; Sauro et al. 2009). The question of whether the fills can constitute important records for the reconstruction of climatic-environmental evolution has also been raised recently by Sauro et al. (2009). Their results indicate that the dolines are "filters" for sediments rather than good traps, archiving only some of the climatic and environmental changes. Detailed analyses of the soil on Velebit Mt. have started long ago. For example, soils from Senjska draga have been studied by Gračanin (1931). Bertovic (1975) has presented relations between plant communities and pedosystematic units of soil in the frame of the ecolog-ical-vegetational study of the Zavižan area. Systematic investigations of the larger area soil properties were primarily related to the creation of the Main Pedological Map on the scale 1: 50 000, Senj 1 (Vrankovic 1973) and Senj 3 (Vrankovic 1974). More recent soil investigations of the Štirovača area have been made by Vrbek & Pilaš in 2007. Red soils on Velebit Mt. have been also studied by Urushibara (1976, 1981) in the broader study frame, while general aspects have been presented by numerous authors (e.g. Rogic 1958; Perica et al. 2002a). STUDY AREA - GEOMORPHOLOGICAL AND ENVIRONMENTAL PROPERTIES Velebit Mountain extends along the Adriatic coast in a NW-SE direction (Fig. 1). It is the longest mountain of the Dinarides mountainous system and of the Republic of Croatia. Velebit Mt. is characterised by anticlinal folding and high degree fracturing. In its different parts they differ in strike, in their inter-relations and in the degree of fracturing. Consequently, three major zones can be distinguished in the structural sense: north Velebit with Senjsko bilo, and central and south Velebit. Velebit Mt. is mainly constituted of Mesozoic carbonate sequences, from Triassic to Upper Cretaceous, upon which synorogenetic calcareous Jelar breccia can be found, particularly on the littoral side. The whole succession ranges from Middle Permian to Quaternary deposits. The impermeable layers outcrop on central and south Velebit. The significant prevalence of carbonate rocks (limestones and, to a lesser extent, dolomites), which are strongly broken up by tectonic movements, enables the formation of typical karstic relief. The littoral slope of the Velebit Mt. reveals its bulky character. It is represented by a huge area of rocky karst. Generally, the littoral slope has a particular step-like morphology. After the steep littoral area of about 100 m high, the first levelled surface appears at 100 to 300 m above sea level. After the steep rise, there is another more or less levelled surface at 700-900 metres a.s.l. This shallow depression is composed of a series of karstic uvalas, some of which have merged together into big ones with large flat bottoms. The genesis of both levelled surfaces is still under debate (Bognar 1992, 2006; Prelogovic 1995). The top parts of Velebit Mt. are characterised by numerous particularly deep karstic forms due to strong tectonic influence, long-lasting karstification as well as to past glacial processes. Well-preserved moraine material has been found at the top parts of the mountain, as well as fluvioglacial sediments on its lower parts (Bog-nar et al. 1991; Bognar et al. 1997; Bočic et al. 2008; Bočic et al in press). At present, together with the karstic processes, periglacial and nival processes (Perica et al. 2002a) strongly influence relief development. Velebit is poor with water, but the foot of the NE slope is characterised by frequent springs. Their appearance is the consequence of the complete hydrological barrier of Velebit Mt. The water flows up to the contact with a broken carbonate base, where it sinks and then flows below the surface towards the sea and towards the Zrmanja River (Biondic 1981). The carbonate base, tec-tonically broken up, results in rivers being rare. The sur- face flows are linked with the poljes that occupy a large area at the foot of the inland Velebit slope. Numerous factors influence the development of pedological cover. On Velebit Mt. those are climatologi-cal, lithological, geomorphological, vegetational and, in more recent times, zoogenic and anthropogenic factors (Perica et al. 2002b). In the upper parts of the mountain, above 900 m, the rendzina and calcomelanosol dominate. Calcocambisol and litosol are often found on the SW slope of the mountain, particularly in its lower parts. Terra rossa is widespread at low altitude, but rarely continuous (Urushibara 1981). In most cases, terra rossa has polygenetic origin and was formed by mixing of insoluble residue of carbonate rocks with other weathered and eroded sediments (Durn 1996; Durn et al. 1999). The thickness of the terra rossa deposits depends on its position with respect to the relief (Benac & Durn 1997). At the same time, terra rossa is a paleosoil, a residual soil and a very old and very eroded soil. It can be totally un-carbonated (Nicod 2003b). As karst processes operate in the atmosphere-soil-epikarst system (Barany Kevei 1993, 1995; Pfeffer 1995), the climatological properties are very important. Velebit Mt. represents a barrier that does not allow mixing of the lowest air masses on both slopes up to 1,000 m altitude. The lowest part of the sea side slope has an average temperature around 15°C and the inland area around 8.8°C. The relief influence becomes distinct in the amount of precipitations. Even if the lowest parts on the sea side receive around 1,100 mm of precipitations per year, the summer months are dry (^ of yearly precipitation is in the warmer part of the year). The amount of precipitations grows with altitude so that precipitation stands at over 2,000 mm per year above 900 m, with more uniform distribution (Perica & Orešic 1997). Fig. 1: Study area. The soil and climatic properties reflect that of the vegetation, which succession is classic for the Mediterranean mountains (Horvat 1949). On the littoral side, forest cover is significantly degraded and is completely degraded to pastures in some areas, what can be partly explained by the economic activities that have occurred in the area (Rogic 1958). The natural properties of Velebit Mt. did not provide predispositions for considerable settlement. However, archaeological findings point to the existence of numerous prehistorical (Mesolithic to Iron Age) settlements on the littoral Velebit side (Glavičic 1995). The existence of coastal settlements in Roman times is known from the Tabula Peutingeriana, Ptolemai map (Markovic 1993; Kozličic 1995) and archaeological findings (Zaninovic 1980; Nedved 1995; Fadic 1995; Gluščevic 1995). All the Roman settlements were located at the foot of the mountain passes, which allowed communication with the inland. The absence of cartographic documentation and sources make the geographical reconstruction for this early period very difficult but the relatively slow degradation of the landscape during the 18'h century indicates that the littoral slope was most probably already denuded before the 16'h century. The number of inhabitants on the Velebit littoral slope during the 14*^ and 15*^ centuries cannot be estimated, even roughly. Nevertheless, various documents confirm the small number of sedentary population. The local community lived from agriculture, but cattle breeding were the basis of the economy (Rogic 1958). In the second half of the 15'h century, the invasion by the Turks in Lika and north Dalmatia result in almost complete depopulation of the littoral slope. Later, at the end of the 17'h century, there were around 2,000-2,500 inhabitants in the northern part and 1,205 in the southern part of the Velebit littoral slope (Rogic 1958). The continuity of settlement on the Velebit littoral slope can be followed from the end of the 17th century. Some well-conserved Venetian cadastral maps of the area (Disegno delle ville di Starigard di Zara 1709; Ru-briche delle ville del Contado Superiore di Zara 1709), published in 1709, show that the landscape was generally similar to the present-day one. Those maps also show that the settlements were located on the first levelled surface and confirm the existence of the summer habitats on the upper levels of the Mountain (Rogic 1958). The basis of the economy was still cattle breeding. In the 18th century, the number of inhabitants increased along with the number of cattle, which generated the problem of exhaustion of pastures that first appeared on the lower part of the Velebit littoral slope. From the beginning of the 18'h century till the year 1850, the number of inhabitants on the southern littoral slope had quadrupled from 1,205 to 4,194. The number of cattle increased at the same time as well, which directly influenced the degradation of the landscape. At the end of the 18'h century, the settlements were finally stabilised, so that the population reached 8,400 inhabitants by the mid-19'h century, which resulted in general poverty and a more intensively degraded landscape. In 1850, the population rose to 12,600 inhabitants (Rogic 1958). In the period between 1850 and 1955, the settlements on the Velebit littoral slope were still very small. Most of them (86%) were located at the contact zone between the first levelled surface with a steep slope, since the littoral zone is not attractive for agricultural and farming communities. This area with local Promina conglomerates and Pleistocene marls (Rogic 1958) allows the existence of ponds, which give water for cattle and provide small depressions suitable for agriculture. The uvalas of the upper levelled surface are much less inhabited, even though there is more arable land at this level - 46% compared to 39% at the lower level. 15% of the arable land can be also found in the high mountainous zone dispersed in the wood clearings of North Velebit. The majority of the agricultural land-owners from the lower levelled surface - 67% - had their properties composed of several parcels at the lower levelled surface, a larger arable part at the upper uvalas, and several isolated fields at the upper mountainous level (Rogic 1958). This kind of dispersed land property resulted in periodical settlement. Such vertical control of space allowed acquisition of enough land for survival and production of different crops: cereals at the lower levelled surface, cereals and potatoes on the upper uvalas and potatoes up to 900 m altitude. In the first half of the 19th century, the number of inhabitants and cattle greatly increased. As the value of pasture-land was generally very low and as the number of inhabitants became too high for this karstic area so, the degradation of pastures occurred in the second half of the 19th century. From the regular census in the second half of the 19'h century, it can be observed that the population constantly grew till the 1910's, followed by regression till 1948 with a small increase in the 19481953 period. Later, in the second half of the 20'h century, depopulation followed; the agrarian activity decreased and reforestation began (Rogic 1958). Beginning in the Neolithic age and recurring regularly, deforestation resulted in the baring of the soil cover, soil erosion by flowing water, its infiltration into the endokarst and baring of rundkarrren. Deforestation principally occurred during the 17'h-19'h centuries (Farst-Bjeliš et al. 2001; Fdrst-Bjeliš & Lozic 2006) while clearing in the mountain areas was carried out later, in the 18*^ and 19*^ centuries, by burning the land and managing the dolines. This karstic environment has had a direct influence on the type of settlement and on the particular agrarian structure of the area. During the historical evolution, the topographical surface was modified with the aim to obtain arable land. This was achieved in various ways: by clearing out stones and creating stony piles in parcels, by creating terraces for cultivation, filling up the doline bottoms, or even arranging more open fields in the areas of open karst (Nicod 2003b). The removed stones were often used for the construction of dry walls, which were built for many different purposes: delimitation of tran-shumance paths, enclosure of wooded areas, as enclosures for domestic animals, for enclosure (protection) of the land parcels, and stone walls terraces and plantation squares (Faber 1984; Nicod 2003a; Aničic & Perica 2003; Aničic et al. 2004). Small karstic depressions, mainly dolines, have therefore resulted in various human modifications. One of the basic landscape and cultural elements in the Velebit area are the small dolines bordered with dry stone walls, some of which have been analysed in this paper. METHODS On the 3,000 km2 of the larger Velebit Mt. area, there are around ~40,000 dolines (Faivre 2000). As the ecological properties differ along the mountain, we have chosen do-lines on the littoral slope at between 30-300 m altitude, and dolines on the top parts of the mountain at between 900 and 1,300 m altitude. According to the aims of this study, we have also selected dolines which were or still are under anthropogenic influences. From the study of the dolines, many different types of forms can be distinguished resulting from different genetical mechanisms (Sauro 2003). The dolines along the coast (Stinica and Kamenica), are classical corrosional dolines, which appear singly and are rare, while the dolines sampled in the upper parts (Baške Oštarije and Bilensko Mirevo) are located at the bottom of large uvalas and poljes and represent parts of doline fields whose morphogenesis is also related to glacial, periglacial and alluvial processes. Cores and sediment observations have been carried out in 15 dolines with a soil auger: 1 core at Kamenica, 3 cores at Stinica, 7 cores at Baške Oštarije, 4 cores at Bilensko Mirevo and two doline interspaces (1 at Baške Oštarije and 1 at Bilensko Mirevo). Usually, most of the dolines studied are shallow, but the compaction of the sediment and/or the presence of rocks in depth were a problem for digging through the fill. Consequently, we cannot be sure if the complete stratigraphies of the do-lines have been obtained. The soils have been described during the field investigation, specifying: depth, thickness, main macroscopic characteristics of the horizons as well as the vegetation cover. Then, each layer has been sampled to find differences in soil properties related to parent material or environmental evolution (colluvial contributions in particular). Sediment analyses in the laboratory have been made on the more representative and deepest ones: six dolines localised on the top (4 at Baške Oštarije and 2 at Bilensko Mirevo) and two do-lines in the lower part near the coast (1 at Kamenica and 1 at Stinica) (Fig. 1). As a whole, the sedimentary fills of 8 dolines have been analysed in more detail and 2 doline inter-spaces. Physical and chemical analyses were done (colour, grain size, pH, CaCO3, C, N, P, K, Mg, CEC). Colours have been determined on dry soils using standard soil colour charts (Munsell Soils Color Charts 1994). Particles size analyses have been determined with a laser granulometer (LS 350, Beckman Coulter), after organic matter destruction and prior sodium pyrophos-phat dispersion of the clay particles. The pH (water) was obtained according to the French norms (NF) ISO 10390. Calcium carbonates content was determined by hydrochloric acid (HCl) using a calcimeter of Bernard (NF ISO 10693). The proportion of carbon and nitrogen was determined after dry combustion (NF ISO 10694 and ISO 13878). The phosphorus rate was analysed by spectrocolorimetry (Joret & Hebert 1955), the rates of potassium and magnesium by an extraction with ammonium acetate (Thomas 1982) and the cation exchange capacity (CEC) by the Metson method (Metson 1956). No paleoecological remains and good material for radiocarbon dating have been found. RESULTS THE DOLINES LOCATED NEAR THE COAST There are almost no dolines on the littoral side of the mountain as it is characterised by the lack of vegetation and the lack of water. Nicod (1967) has demonstrated on the karst of Provence that dolines do not develop on rocky karst because there is no soil and no vegetation. On the lower part of the slope, some rare small shallow pen-shaped dolines can be observed, 5-10 m deep, which indicates their feeble vertical development. Among the rare and isolated dolines, two sites, Ka-menica at 280 m and Stinica 30 m above sea level, have been selected for this study. Both dolines have been formed on the Palaeogene calcareous breccias, that is, on Jelar deposits (Mamužic et al. 1969). A) Kamenica Kamenica is positioned on the foot slope. It is formed slightly above the lower levelled surface (Fig. 2). Kamenica is ~1.5 km far from the sea and it is at 280 m above sea level. It is like a small uvala around 100 m wide with dolines, in which small settlements with only several houses can be found. After a few tests, the best core is obtained from the edge of Kamenica (Kamenica 1). It was only 25 cm long (stopped by rock). The analyses showed a brown clear (7.5YR4/4) clayey soil (clay: 60%, fine loam: 27%), with a grumous to polyhedral structure. The soil is decalcified. The pH is not very high in comparison with other Fig. 2: Kamenica doline (Google Earth). 64 ACTA CARSOLOGICA 41/1 - 2012 context, but the nutrient elements are well-represented (Tab. 1). The sedimentary sequence is shallow and does not allow efficient observations of environmental dynamics. B) Stinica Stinica is quite large; it is more than 100 m in diameter and is 70 m deep. It is located near the sea, less than 100 m away (Fig. 3). Today, Stinica is characterised by cultivated terraces around the doline. According to its size and position, Stinica has surely had a long-lasting evolution. According to inscriptions from Antiquity the main trail probably started near Stinica close to the seashore, as a several kilometres long boundary wall starts right there and continues on towards the upper Velebit area. Another Roman inscription found near this wall speaks about an agreement, probably referring to grazing boundaries between the Ortoplins (Illyrian tribe from today's Stinica) and the neighbouring Begos tribe (Faber 1984). Thus, this doline was probably used long ago, since cattle-breeding developed together with land cultivation in prehistoric times (Faber 1984, 1995a, 1995b). Fig. 3: Stinica doline (yellow arrow) and Bay of M. Stinica (green arrow) - today submerged doline. One core at the bottom and two cores on the first terrace have been made. Most of the time, the calcareous fragments were too numerous to dig after 20 or 30 cm of depth. At the bottom, as on the first terrace (Stinica 1), the soil is brown on the surface (3 cm of humiferous horizon) and reddish (5YR4/6) at depth (Tab. 1). The sediment has the same characteristics everywhere. It is very clayey (74%) with a small proportion of fine loam (17-18%). It presents the finest texture we observed. It has a polyhedral to grumous structure. The sediment is decalcified. The organic matter and the proportion of nutrients is higher on the surface (N, Mg and K) (Tab. 1). It contains numerous angular calcareous fragments (1 to 2 cm in diameter on average) that attest to colluvial contribution. Another similar doline has been observed south-westwards from the Stinica doline, the former being submerged today as a consequence of glacioeustatic changes and tectonic movements during the Holocene (Fig. 3). Fig. 4: The cross section of the Stinica doline with sampling locations. THE DOLINES LOCATED ON THE TOP OF THE MOUNTAIN Dolines can appear singly, as was the case on the littoral slope, but they usually appear at the top parts of the mountain as doline fields, where the density highly increases and reaches till 121 dolines per km2. Two major locations have been chosen: the polje of Baške Oštarije and the uvala of Bilensko Mirevo (Figs. 5 & 6). The Baške Oštarije polje is an area of contact karst developed on the boundary between more and less permeable rocks; accordingly, considered as marginal karst polje (Gams 1978; Perica et al. 2002b). The second location at Bilen-sko Mirevo is an ancient terminal basin with numerous small dolines. A) Baške Oštarije The Baške Oštarije pass (at 928 m altitude), situated on the main road which crosses Velebit Mt., corresponds to the most narrow part of the mountain. Along the transversal fault of Brušane, the Triasic dolomites are in contact with Permian - Werfenian sediments. The small Baške-Oštarije polje has developed along this contact zone (Perica & Buzjak 2001). The polje stretches out in an E-W direction; it is 3.75 km long and its width varies from 0.25 to 2.0 km. Together with the Suvaja Valley, it divides the central from the southern part of Velebit Mt. Besides karst and fluvio-karst, the derasion and perigla-cial processes have been mostly expressed in the relief formation of the area (Perica et al. 2002b). Clastic-carbonate deposits of the Middle-Upper Triassic (Ladinian-Norian) period crop out in the area of Prpici at Baške Oštarije. The underlying deposits of Ani- sian age are palaeokarstified floatstones and rudstones, with interbeds of dark peloid-ooid packstone-wacke-stones with stromatolitic laminae (Sokač et al. 1974; Velic et al. 2006). In the area of microtectonically fractured carbonates, which are found between three major faults, numerous dolines and sinks (swallow holes) have been formed. Dolines are also sporadically formed in alluvial sediments of the lowest part of the polje at around 900 m altitude and are partly filled with periglacial slope deposits. The central position of this natural pass has had very high importance throughout history (Perica 1998). In the dolines of the Oštarijsko polje, the autochthonous forests have been destroyed by fire in order to obtain agricultural areas during the 18th and 19th centuries. As a consequence of the forest devastation and usually short-lasting rainfalls, strong surface erosion of pedogenetic horizon occurs. Therefore, rocky karst predominates today. Strong outwash is also indicated by continuous occurrence of ash particles in pedohorizons up to 2.2 m and colluvial soils at swallow holes (Fdrst-Bjeliš et al. 2001). The doline density at Baške Oštarije varies around 15 doline per km2 (source topographical map 1: 25 000). Seven cores have been done at the Baške Oštarije area (Fig. 5). One core has been done between the dolines (BO3) in the relatively lower part of the basin. It shows 40 cm of a brown (7.5YR4/4) and silty-clay soil. The others have been obtained from the dolines. The most representative ones have been chosen for physical and chemical analyses. Several differences have been observed. The soils can be distributed in two groups: the dolines in relatively upper (BO2 and BO5) and in relatively lower position (BO1 and BO7) in the basin. In the upper position, BO2 is a little doline (5 m in diameter). The core was 40 cm deep. The sediment is brown (7.5YR4/4), silty-clay (clay: 37-57% and fine loam: 34-35%), with a polyhedral structure. At the surface, the granulometry tends to be finer, and the organic matter and the nutrient contents are higher (CEC, P, Mg, N). In depth, the content in CaCO3 increase in feeble proportion. BO5 is somewhat higher in elevation with 7 m diameter and is enclosed with a dry stone wall. The sediment is still brown (7.5YR4/4), silty-clay (clay: 38-40% and fine loam: 40-43%) with a polyhedral structure. The granulometry is nearly homogeneous along the first 40 cm of depth. The sediment is Fig. 5: Polje of Baške Oštarije with sampling locations (Photo: S. Faivre). decalcified. The proportion of organic matter and soil nutrients is more important at the surface (CEC, P, K, Mg, N) as in BO2. The dolines in relatively lower position present brown to brown-red soils (7.5YR4/4 to 7.5YR4/6 in particular in depth). The sediment is silty clay, always with a small quantity of sand (1.3 to 10,6%). It has a polyhedral structure. The pH is high and the CaCO3 contents are higher than in BO2 and BO5. The BO1 (40 cm) core was made in a rectangular field not really in the lower part of Baške Oštarije, but just lower than BO2. In BO1, the sediment is small-sized (clay: 52-59% and fine loam: 29-34%) and richer in organic matter and nutrients in depth (CEC, K, Mg, N). The higher proportion of CaCO3 at the surface could attest to colluvial contributions. In the BO7 (55 cm) core, the grain size (clay: 48-61% and fine loam: 27-35%) is finer and the nutrient content rises in depth. The finer grain size and the maximal cation exchange capacity - the organic matter, P, K, Mg, N, are in fact higher in the middle of the core (near 45-50 cm of depth). Up to this horizon, the soil shows impoverishment (as in BO1). We note that we have not sampled the surface of BO7, so the vertical evolution of the CaCO3 content cannot be verified. of the glacier tangs (Bognar et al. 1991). Such terminal moreinic volumes remodelled karstic heritage by the superpositioning of glacio-karstic and nivo-karstic morphologies as it is also the case e.g. in the Pyrenees (Auly 2007). Consequently, structural predisposition and karstic morphology and the extent of the thick cover of Pleistocene sediments here, together influenced pedogenetic phenomena. Fig. 6: Dolines in glacial moraine deposits at Bilensko Mirevo (Photo: S. Faivre). B) Bilensko Mirevo During the Quaternary glacial phases, Velebit Mt. knows a cirque, plateaux and valley glaciers, which leave different types of moraines. Consequently, the glacio-karstic forms are beautifully developed all over the mountain. One particularly interesting site is the uvala of Bilensko Mirevo, which was a former terminal basin where the 4 km long Alan glacier melted. Relatively thick moraine material indicates several phases of Quaternary pulsations and the progressive retreat Middle Jurassic carbonate beds, mainly grey to dark grey thick layered and massive mudstones, with occasional scud of late digenetic coarse crystallised grey-brown dolomite (Sokač et al. 1974; Velič & Velič 2009), can be found below the moraine deposits. Seepage through thick unconsolidated regolith or allogenic detritus over karst rocks generates suffusion depressions. Suffosion causes a dimpling of the surface with a multitude of small dolines at Milensko and Tab. 1: , š| Results i rn s un ro c^ £ CO vo 0 u^ c^ ro 0 JT CN 0 LO 0 r-^ VD CN - m vd CS CN CN CS 0 CN ü ü r^ CN E V LO LO l^n CD 0 r^ LO CO ro C^ C^ vo c^ LO i J=