HACQUETIA 9/1 • 2010, 5-17 DOI: 10.2478/v10028-010-0006-y NOMENCLATURAL-PHYTOCOENOLOGICAL ANALYSIS OF THE ASSOCIATION POtEMtlLLO MICRAntHAE-QUERCEtUM PEtRAEAE ASS. NOVA IN CROATIA Joso VUKELIČ1, Dario BARIČEVICi & Irena ŠAPICi Abstract Phytocoenological traits of forests of sessile oak in the area of Zrinska Gora were investigated in 2009. Phy-tocoenological research was conducted using a method of the Zürich-Montpellier School. A comparison was made with acido-thermophilic forests of sessile oak from central and north-western Croatia, then from Slovenia and the Mescek Mountains in Hungary. A statistical comparison was made by entering all the phytocoenological releves into the Turboveg database. This was followed by a classical synthetic analysis of the phytocoenological releves and a multivariate analysis using Syntax 2000 software. Average Ellenberg's values were calculated for each releve with JUICE 6.3 software. Taking into consideration all the facts, it can be concluded that the newly established association Potentillo micranthae-Quercetum petraeae shows a high degree of independence and differentiation from other similar associations described to date. In relation to others, it is poorer in species, both in terms of the systematic categories to which it belongs and the number of elements from the orders of Fagetalia and Quercetalia pubescentis. Of the species occurring in acidophilic forests of sessile oak, Genista tinctoria, Chamaecytisus hirsutus and Dicranella heteromalla can be considered characteristic species, whereas Galium sylvaticum, Cephalanthera longifolia, Dianthus armeria and Viola alba can be termed differentiating species. The species Potentilla micrantha, Festuca drymeia and Luzulaforsteri are very important for the structure, physiognomy and syndynamics of the association. It is subordinated to the alliance Quercion robori-petraeae, the order Quercetalia robori-petraeae and the class Querco-Fagetea. Key words: nomenclatural-phytocoenological analysis, acidophilic forests, Potentillo micranthae-Quercetum e, Zrinska gora, Croatia. Izvleček V letu 2009 smo preučevali fitocenološke značilnosti gozdov gradna na območju Zrinske gore. Raziskavo smo naredili z metodo Züriško-Montpellierske šole. Primerjali smo acidofilno termofilne gradnove gozdove iz srednje in severozahodne Hrvaške s podobnimi iz Slovenije in hribovja Mecsek na Madžarskem. Za statistično primerjavo smo zbrali fitocenološke popise v bazi Turboveg. Sledila je klasična sintetska analiza fitocenoloških popisov in multivariatne analize s programom Syntax 2000. Povprečne Ellenbergove indikacijske vrednostiza posamezen popis smo izračunali s programom Juice 6.3. Primerjava nove asociacije Potentillo micranthae-Quercetum petraeae kaže visoko stopnjo neodvisnosti in razlik od podobnih dotedaj opisanih asociacij. V primerjavi z njimi je preučevana asociacija vrstno siromašnejša, tako v številu sinsistematskih kategorij kot po številu elementov iz redov Fagetalia in Quercetalia pubescentis. Za značilnice, ki se pojavljajo v acidofilnih gradnovih gozdovih lahko imamo vrste Genista tinctoria, Chamaecytisus hirsutus in Dicranella heteromalla, medtem ko vrste Galium sylvaticum, Cephalanthera longifolia, Dianthus armeria in Viola alba označimo kot razlikovalnice. Vrste Potentilla micrantha, Festuca drymeia in Luzula forsteri so zelo pomembne za strukturo, fizionomijo in sindinamiko asociacije. Uvrščamo jo v zvezo Quercion robori-petraeae, red Quercetalia robori-petraeae in razred Querco-Fagetea. Ključne besede: nomenklaturno-fitocenološka analiza, acidofilni gozdovi, Potentillo micranthae-Quercetum petraeae, Zrinska gora, Hrvaška. 1 University of Zagreb - Faculty of Forestry, Department of Ecology and Silviculture, Svetošimunska 25, p.p. 422, HR - 10002 Zagreb 1. INTRODUCTION Acido-thermophilic forests of sessile oak, placed in the order of Quercetalia robori-petraeae, grow in the colline and montane belt of northern Croatia (300-800 m). The soil is acidophilic and the climate is temperate (9-11 °C, precipitation 800 to 1100 mm). Sessile oak, the dominant species in the tree layer, is permanently accompanied by sweet chestnut (Castanea sativa), manna ash (Fraxinus ornus) and wild service tree (Sorbus torminalis), while beech and hornbeam (Fagus sylvatica and Carpinus betulus), except in some sporadic stands with sweet chestnut, have a subordinate role. Compared with the related Central European associations of the same syntaxonomic affiliation (Luzulo-Quercetum Hillitzer 1932, Genisto pilosae-Quercetum Zolyomi et al. 1957, partly Melampyro vulgati-Quercetum petraeae Puncer et Zupančič 1979 and others), these forests are characterized by the presence of a large number of species predominantly distributed in southern and south-eastern Europe. These include acido-ther-mophilic species Castanea sativa, Chamaecytisus hirsutus, Luzula forsteri, Lathyrus linifolius, Dian-thus barbatus, and thermophilic species on acid soils Fraxinus ornus, Sorbus torminalis, Potentilla micrantha, Campanula persicifolia, and Sedum tel-ephium ssp. maximum. Besides these, the following differentiating species of predominantly mesophilic character are also important: Crucia-ta glabra, Galium sylvaticum, Cephalanthera longi-folia, Festuca drymeia, Carex pilosa and others. On the other hand, Betonica officinalis, Teucrium scordonia, Genista pilosa and Deschampsia flexuosa are either absent or occur very rarely in sessile oak communities in Croatia, while Calamagros-tis arundinacea, Vaccinium myrtillus and Calluna vulgaris are relatively rare. In contrast to central Europe, tree species such as Pinus sylvestris, Picea abies, Quercus robur, Sorbus aucuparia and Fraxi-nus excelsior do not occur at all (Horvat 1938, Sugar 1972, Hruška Dell' Uomo 1974, Vukelic 1991, Vukelic & Baričevic 1996, Baričevic 2002, Trinajstic 2008, Vukelic et al. 2008, Medak 2009). For reasons of floristic, geobotanic and ecological differences, it was proposed that the above associations growing south of pre-Alpine-Alpine areas be placed into separate alliances or subal-liances (Soo 1962, 1971, Vukelic 1991). This has already been done with the suballiance Castaneo-Quercenion (Soo 1962 em. 1971) Kevey in Kevey et Borhidi 2005. Phytocoenological traits of forests of sessile oak in the area of Zrinska Gora were investigated in 2009. As the phytocoenological analysis showed, these forests could be described as a new association due to the fact that they differed in some basic characteristics from the associations described earlier. The new association was named Potentillo micranthae-Quercetum petraeae. A comparison was made with acido-thermophilic forests of sessile oak from central and north-western Croatia, then from Slovenia and the Mescek Mountains in Hungary. 2. MATERIAL AND METHODS Phytocoenological research was conducted in 16 localities on Zrinska Gora using a method of the Zurich-Montpellier School (Braun-Blanquet 1964) with a six-point scale. Phytocoenologi-cal releves were taken from the plots of 400 m^ between April and August 2009. Sixteen releves with their participation percentages are presented in analytical form in Table 1, whereas a comparison between the studied communities and the related communities in adjacent areas (Luzulo forsteri-Quercetum petraeae from Mescek, Festuco drymeiae-Quercetumpetraeae from Moslovačka gora, Hieracio racemosi-Quercetum petraeae from NW Croatia and Melampyro vulgati-Quercetum petraeae „submediterraneum'" from Brkini) is shown in Table 2. The species participation percentage in all the releves is also given. A statistical comparison was made by entering all the phytocoenological releves into the Tur-boveg database (Hennekens & Schaminee 2001). This was followed by a classical synthetic analysis of the phytocoenological releves and a multi-variate analysis using Syntax 2000 software (Podani 2001). Two methods of multivariate statistical analysis were used: cluster analysis (complete link, group average, simple average, incremental sum of squares) and multivariate scaling (Principal coordinate analysis /PCoA). The measure of dissimilarity or similarity was the complement of the "Similarity ratio" coefficient. Average Ellenberg's values were calculated for each releve with JUICE 6.3 software (Tichy 2002). The obtained data were processed with STATISTICA 8.0 (StatSoft Inc 1984-2008). The Kruskal-Wallis test was used to determine which ecological factors were important for distinguishing the associations. Scientific names of the higher plant species follow the web source - Flora Croatica Database (2004) (http://hirc.botanic.hr/fcd/), and the mosses are adjusted according to Koperski et al. (2000). The names of plant communities are coordinated by the valid Code of Phytocoenological Nomenclature (Weber et al. 2000). 3. ECOLOGICAL FEATURES OF THE STUDY AREA Zrinska Gora is situated in a wider area of the River Sava on the south-western edge of the Pan-nonian Plain and in the boundary area with Bosnia and Herzegovina. The massif is characterized by a distinctly indented relief with numerous elongated ridges and deeply cut stream valleys. It reaches a height of up to 616 m. The majority of the massif is covered with deciduous forests (oak, beech, chestnut), whereas lower slopes feature pastures and arable land (Baričevic et al. 2009, Medak 2009). The area of Zrinska Gora is made up of sediment, igneous, ultramaphitic and metamorphic rocks chronostratigraphically distributed from the Palaeozoic to the Quaternary. Most frequently, these are layers of marl, clay, sandstone, sand and gravel with limestone participation. The dominant soil types are luvisol, cambisol, ranker and colluvium. Zrinska Gora is located at a meeting point of two large relief units: the southern edge of the Pannonian Plain and the northern part of the pre-Dinaric space. Data for Sisak Meteorological Station for the period 1980 to 2006 (source: State Hydro-Meteorological Office) show that, according to Köppen, the climate in the Banovina area is temperate warm and rainy (Cfwbx" type). The mean annual air temperature is 11.1 °C, and the mean air temperature in the vegetation pe- Figure 1: Characteristic appearance of the association Potentillo micranthae-Quercetum petraeae in the area of Zrinska gora Slika 1: Značilen videz asociacije Potentillo micranthae-Quercetum petraeae na območju Zrinske gore. riod is 17.7 °C. The total annual precipitation is 905.7 mm, of which 508.9 mm, or 56.19 %, occurs in the vegetation period. The investigated association is predominantly developed on southern expositions, at heights between 300 and 500 m above the sea, with inclinations ranging from 5 and 35 degrees (Figure 1). The dominant soil types are luvisol and dystric cambisol. In the adjacent community Apo-seridofoetide-Castanetum sativae, which is the most represented chestnut phytocoenosis on Zrinska Gora, seven analyzed profiles contain luvisol, in which the pH of the humus-accumulative horizon ranges between 5 and 5.5 (Medak 2009). 3. RESULTS AND DISCUSSION The floral composition of the association under study is shown in the analytical Table 1. A total of 66 species of higher plants and 9 of mosses were recorded in the releves. Of these, 24 species are present in over 50 % of the releves. These include the basic species of the order Quercetalia robori-petraeae and lower units: Castanea sativa, Luzula luzuloides, Hieracium racemosum, Genista tinctoria, Festuca heterophylla, Veronica officinalis, Luzula forsteri, Chamaecytisus hirsutus and the moss Di-cranella heteromalla. Ten species from the order Fagetalia and lower units were identified (Fagus sylvatica, Festuca drymeia and Galium sylvaticum in over 50 % of the releves) and 10 from the order Quercetalia pubescentis, of which 3 occurred in over half of the releves (Fraxinus ornus, Sorbus torminalis and Potentilla micrantha). The association Potentillo micranthae-Querce-tum petraeae was compared with four associations from neighbouring areas, with which it manifests the highest similarity (Table 2). They all belong to the same syntaxonomic units, with sessile oak as the edifier. In relation to similar forests north of the Alps, they are characterized by the Mediterranean influence, which has had an effect on their floristic composition. In addition to the larger number of species from the order Querceta-lia robori-petraeae, there are also mesophilic species of the order Fagetalia and thermophilic species of the order Quercetalia pubescentis, depending on the local characteristics of the mountains. The following associations were compared: Festuco drymeiae-Quercetum petraeae (Jankovic 1968) Hruška Dell' Uomo 1974 stretches from Fruška Gora in the east to Moslavačka Gora in the west, where it represents the boundary community Quercetalia robori-petraeae towards beech and hornbeam forests (Hruška Dell' Uomo 1974, Jankovic & Mišic 1980, Baričevic 2002). Compared with the analyzed communities, the differentiating species, besides the dominant Festuca drymeia, include "fagetal" mesophites Dryopteris filix-mas, Euphorbia amygdaloides, Mycelis muralis, Galium odoratum, Salvia glutinosa, Sanicula europaea, Cyclamen purpurascens and others. The overall number of the species in this and the compared association Potentillo micranthae-Quercetum petraeae is 142. There are 43 species, or 30 %, occurring in both associations. Luzulo forsteri-Quercetum petraeae (A.O. Horvat 1963) Borhidi et Kevey 1996 is described as the local association of the Mescek Mountains in Hungary. Occurring at heights between 300 and 500 m, it covers northern expositions and inclinations of 3 to 25 degrees. The floral composition features some important sub-Mediterranean species, which discriminates this association from other acidophilic forests in the Mescek Mountains, the west Zadunavlje region and central Hungarian uplands (A. O. Horvat 1972, Borhidi and Kevey 1996, Kevey 2008). This analysis showed some similarities with the mountains of western Croatia. Compared with the analyzed forests of Western Balkans (Table 2), the differentiating species feature Hieracium lachenalli and Veronica officinalis in the first place, then Prunus avium, Symphytum tuberosum and Brachypodium sylvaticum of the order Fagetalia and species of wider social affiliation Pyruspyraster, Crataegus mo-nogyna, Melica uniflora, Rosa arvensis, Carex digi-tata and Hepatica nobilis. Special mention should be made of the differentiating importance of the species Quercus cerris, Tilia tomentosa and Genista tinctoria ssp. ovata, which do not occur in related communities, or at least not in such numbers. The percentage of common species in comparison with Potentillo micranthae-Quercetum petraeae is only 29 %. Hieracio racemosi-Quercetum petraeae Vukelic 1991 nom. invalid occurs on southern slopes of north-western mountains in Croatia, where it reaches a height of 700 m. It grows on shallow and medium deep dystric cambisol above schists and sandstones. Due to the geographic position there is a more distinct presence of acidophilic forests of the central European region. In addition to other species, the association features Vaccinium myrtillus, Calluna vulgaris, Molinia caerulea ssp. arundinacea, Calamagrostis arundinacea, Prenant-hes purpurea, which are either absent or much less frequent in sessile oak communities growing more eastwards. Particularly distinct are Hiera-cium umbellatum, Lathyrus linifolius, thermophilic Lathyrus niger, Tanacetum corymbosum, Sorbus aria and fagetal Knautia drymeia ssp. drymeia and Cruciata glabra. The total number of species also occurring in the association Potentillo micranthae-Quercetum petraeae is 130, of which 37 are common to all (28 %). Melampyro vulgati-Quercetum petraeae „submed-iterraneum" Puncer et Zupančič 1979, described in the area of Brkinov in Slovenia, covers southern positions up to 740 m. It contains a large number of differentiating species of acidophilic forests of sessile oak from the Atlantic - sub-Atlantic and continental region. In addition to the species mentioned in the previous association, of special interest are Potentilla erecta, Chamaespartium sag-ittale, Deschampsia caespitosa, Genista pilosa, Juniperus communis and others (Puncer & Zupančič 1979). There are 23 % species that also occur in the association Potentillo micranthae-Quercetum petraeae. The association Potentillo micranthae-Querce-tum petraeae features the fewest number of species. Its differentiating species clearly discriminate it from other associations. Of the syntaxo-nomic categories to which it belongs, it contains the species Genista tinctoria, Chamaecytisus hirsutus and the moss Dicranella hetermomalla. Beech species include Cephalanthera longifolia and Galium sylvaticum, and species of broader sociological tolerance include Viola alba and Dianthus armeria. This set of differentiating species characterizes the community both in the sociological and ecological sense. Potentilla micrantha, the species which gives the association its name, is a clear indicator of ecological-sociological relations in the association. Potentilla micrantha is a species of dry, slightly acidic, medium poor to rich, skeletal, aerated soils, semi-light terrains and warm sites. It is native to southern and especially south-eastern Europe and Asia Minor. It is significantly represented in forests of oriental hornbeam (Carpinus orientalis) in northern Greece, southern Bulgaria and Macedonia, subcontinental forests of sweet chestnut (Castanea sativa), and especially in forests of Hungarian oak in Serbia (Quercus frainet-to). Thus, in the thermophilous deciduous forests in Southeastern Europe (Bergmeier & Dimopou-los 2008, čarni et a. 2009). In the western part of the Balkan Peninsula it is very common in acido-philic forests of sessile oak and continental chestnut forests, but less frequent in Illyrian beech forests of the alliance Aremonio-Fagion. It may even reach the range of Illyrian beech-fir forests. Most authors classify it among the characteristic species of the order Quercetalia pubescentis, and less frequently among Quercetalia robori-petraeae. Five described associations with a total of 93 releves were compared in Table 2. 88 species were identified which either differentiate the associations from one another or from group to group. These species largely coincide with the species which the authors have denoted as characteristic or differential in the original description of the associations. However, the species that identify the association do not include only the differentiating and other species, but also those that do not grow in the association but are represented in other associations. This "negative differentiation" is partly reflected in the results of statistical comparison of the associations in Table 2. Namely, a comparison of the associations, especially the species of the order Quercetalia robori-petraeae, gives the impression that the studied association is the most similar to the association Luzulo for-steri-Quercetum petraeae from Mescek in Hungary, and that it could possibly be joined to the latter. These two associations are linked by a large number of joint species from the order Quercetalia robori- petraeae. Other important links are Luzula forsteri, Tilia tomentosa and Potentilla micrantha. Statistical analysis (Figure 2), however, shows completely different relations. These associations are different and individual at a very high level. The Hungarian association, in comparison with the others, shows distinct independence. Unfortunately, in the releves at our disposal, no mosses were recorded in the association derived from the Mescek Mountains. With mosses, the comparison would be more reliable. The difference between the association Potentillo micranthae-Quer-cetum petraeae and the others is reflected in the fact that the former either lacks or contains very few of the important species of acido-thermophil-ic sessile oak forests, such as Melampyrum vul-gatum, Chamaecytisus supinus, Solidago virgaurea, Lembotropis nigricans and Hieracium sabaudum. Of the species from the order Quercetalia pubes-centis these are Tanacetum corymbosum, Convallar-ia majalis, Lathyrus niger, partly Quercus cerris and others. These species are present in all the other compared associations to a significant extent. A synthetic analysis of 93 phytocoenological releves and multivariate statistical analysis clearly identified five separate groups of releves (Figure 2). The first group is made up of the releves of the association Hieracio recemosi-Quercetum petraeae (1-20), the second groups consists of the releves of the association Luzulo forsteri-Quercetum petraeae (21-45), the third group is formed from the releves of the association Festuco drymeiae-Quercetum petraeae (46-58), the fourth group consists of the releves of the association Potentillo micranthae-Quercetum petraeae from Zrinska Gora (59-74), and the fifth group is made up of the releves of the association Melampyro-Quercetum petraeae submediterraneum (75-93). Cluster analysis and other statistical methods also showed the closest similarity between the association Potentillo micranthae-Quercetum petraeae and the association Festuco drymeiae-Quercetum petraeae. Of all the observed associations, that of Luzulo forsteri-Quercetum petraeae proved to be the most different. The associations from Table 2 were compared in terms of Ellenberg's ecoindicator values of the floristic composition. The Kruskal-Wallis test (p<0.05) was used to determine the ecological factors that were important for differentiating the associations. Ratios for light, temperature, humidity, continentality, as well as soil and nutrient reaction, were taken into consideration. The results are given in Table 3 (bold indicates a statistically significant difference between association Poten-tillo micranthae-Quercetum petraeae and individual associations for each ecological factor). Taking into consideration all the facts mentioned in the discussion, it can be concluded that the newly established association Potentillo micranthae-Quercetum petraeae shows a high degree of independence and differentiation from other similar associations described to date. In relation to others, it is poorer in species, both in terms of systematic categories to which it belongs and the number of elements from the orders of Fagetalia and Quercetalia pubescentis. Of the spe- 32 n 30 28 26 24 22 20 18 16 in 14 Q 12 10 4 2 0-L-d Hr-Q Mp-Q Fd-Q Pm-Q Lf-Q Figure 2: Dendrogram constructed with cluster analysis - Increment sum of squares method. Slika 2: Dendrogram kot rezultat klastrske analize - Increment sum of squares method. cies occurring in acidophilic forests of sessile oak, Genista tinctoria, Chamaecytisus hirsutus and Dicranella heteromalla can be considered characteristic species, whereas Galium sylvaticum, Ce-phalanthera longifolia, Dianthus armeria and Viola alba can be termed differentiating species. The species Potentilla micrantha, Festuca drymeia and Luzula forsteri are very important for the structure, physiognomy and syndynamics of the association. The releve number 15 in Table 1 is taken as the nomenclatural type. The final group of diagnostically decisive species and other features will be determined after the association has been investigated in other Pannonian hills of Croatia and neighbouring areas. The forest of sessile oak with pink barren strawberry is predominantly of primary origin, but some stands are in regression due to anthropogenic impacts, irregular cutting operations and the removal of leaf litter. In the progressive direction, the coenosis develops towards forests of sessile oak and sweet chestnut, while regression ends with bracken and heath. 4. CONCLUSION Phytocoenological research conducted in aci-dophilic forests of sessile oak on Zrinska Gora resulted in the establishment of a new association of sessile oak with pink barren strawberry (Potentillo micranthae-Quercetum petraeae as. nova hoc loco). Growing on dystric cambisol and cam-bisol of acid to weakly acid reaction, it occurs on southern slopes at elevations from 300 to 600 m. It is subordinated to the alliance Quercion robori-petraeae, the order Quercetalia robori-petraeae and the class Querco-Fagetea. Its characteristic species include Genista tinctoria, Chamaecytisus hirsutus and Dicranella heteromalla, and the differentiating species are Galium sylvaticum, Cephalanthera longi-folia, Viola alba and Dianthus armeria. A group of species including Festuca drymeia, Luzula forsteri and Potentilla micrantha is also important for diagnostic identification, structure and syndynam-ics of the association. Some important species of acidophilic and thermo-acidophilic forests of sessile oak are either absent or are present to a much lesser degree than in other communities. These are, for example, Melampyrum vulgatum, Chamaecytisus supinus, Solidago virgaurea, Lembotropis nig-ricans and Hieracium sabaudum, whereas species of the order Querdetalia pubescentis include Tan- acetum corymbosum, Convallaria majalis, Lathyrus niger, partly Quercus cerris and others. 5. 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Akademija šumarskih znanosti, Zagreb, 179 pp. Vukelic, J. 1991: Šumska staništa i zajednice hrasta kitnjaka (Quercus petraea Liebel.) u gorju sjeverozapadne Hrvatske. Glasnik za šumske pokuse 27: 1-82. Vukelic, J. & Baričevic, D. 1996: Fitocenološki odnosi acidofilnih šuma hrasta kitnjaka (Quercus petraea Liebl.) u sjeverozapadnoj Hrvatskoj i nekim europskim područjima. Unapredenje proizvodnje biomase šumskih ekosustava, knjiga I: 79-86. Vukelic, J., Mikac, S., Baričevic, D., Bakšic, D. & Rosavec, R. 2008: Šumska staništa i šumske zajednice u Hrvatskoj - Nacionalna ekološka mreža. Državni zavod za zaštitu prirode, Zagreb, 263 pp. Weber, H.E., Moravec, J. & Theurillat, J-P. 2000: International Code of Phytosociological Nomenclature 3th ed., Journal of Vegetation Science 11: 739-768. Received 10. 11. 2009 Revision received 8. 3. 2010 Accepted 22. 3. 2010 Table 1: Floral composition of the association Potentillo micranthae-Quercetum petraeae. Tabela 1: Floristična sestava asociacije Potentillo micranthae-Quercetum petraeae. Number of releve 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Date 5/09 5/09 5/09 5/09 5/09 6/09 6/09 6/09 6/09 6/09 6/09 6/09 6/09 6/09 6/09 6/09 Altitude (m) 315 320 330 325 340 360 320 300 320 380 350 372 363 429 444 478 Releve area (m^) 400 400 400 400 400 400 400 400 400 400 400 400 400 400 400 400 Exposition (§) 180 80 0 90 60 190 205 170 205 190 180 210 220 190 200 210 Inclination (°) 5 4 30 15 15 20 30 25 35 25 20 35 35 25 27 20 Cover (%) A 90 80 85 95 80 80 70 80 70 75 70 80 80 90 95 90 e B 40 30 30 20 10 20 30 20 40 40 35 35 30 35 35 30 c n e eer C 20 25 85 50 60 60 70 30 90 60 80 85 85 70 65 60 s er g deg Number of species 20 17 28 32 34 27 32 28 27 26 27 28 28 24 35 30 Characteristic and differentiating species of the association Genista tinctoria B + 1 1 + 2 + + 2 1 1 1 + + + + V Chamaecytisus hirsutus + + + + + + + + 1 1 + + + V Galium sylvaticum C 1 + 1 2 + 1 1 1 + + + 1 + V Cephalanthera longifolia + + + 1 + + + + + 1 IV Viola alba + + + + + + + III Dianthus armeria 1 + + + + + II Dicranella heteromalla D + + 1 1 + + 1 + III Quercetalia robori-petraeae Castanea sativa A + + + + + + II Castanea sativa B 1 1 1 1 1 + 1 1 1 1 2 + + 1 + V Genista tinctoria + 1 1 + 2 + + 2 1 1 1 + + + + V Chamaecytisus hirsutus + + + + + + + + 1 1 + + + V Pteridium aquilinum C 1 1 1 + + + 2 3 + 2 4 1 + 1 + V Luzula luzuloides + + + 3 3 2 4 3 2 3 4 + + 1 V Hieracium racemosum + 1 1 1 1 2 1 2 + 1 1 + 1 + + V Festuca heterophylla + 2 2 3 3 1 1 3 1 + + 2 2 1 V Veronica officinalis + + + + + + 1 + III Luzula forsteri + 1 1 1 1 + + + + III Hieracium murorum + + 1 + 1 + II Galium lucidum + + + I Melampyrum pratense + + I Serratula tinctoria + I Aremonio-Fagion Festuca drymeia C 1 2 3 1 3 1 + + 2 2 3 2 3 3 2 3 V Ruscus hypoglossum 1 + + + II Fagetalia sylvaticae Fagus sylvatica A + + 2 + + + + + + III Carpinus betulus + I Fagus sylvatica B 1 1 1 + 1 + 1 + 1 + 1 + 1 V Prunus avium + + + + + II Carpinus betulus + + + I Galium sylvaticum C 1 + 1 2 + 1 1 1 + + + 1 + V Lathyrus vernus Fagus sylvatica Cardamine bulbifera Dryopterisfilix-mas Mycelis muralis Galium odoratum . + . + + + ++ II II I I I I + ++ ++ + + ++ + Number of releve 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Carpinus betulus + I Pulmonaria officinalis + I Quercetalia pubescentis Fraxinus ornus A 1 + + + + II Sorbus torminalis + + I Fraxinus ornus B 1 + + 2 1 1 1 + 2 2 2 1 1 + + + V Sorbus torminalis 1 1 + + + + + + 1 + + 1 + 1 1 + V Chamaecytisus supinus + + I Cornus mas + I Sorbus domestica + I Potentilla micrantha C + + 1 + + + + + + + 1 + IV Fraxinus ornus + 1 1 1 + + + 1 III Campanula persicifolia + + + + + + II Sorbus torminalis + + + 1 II Melittis melissophyllum + + + I Lathyrus niger + + 1 I Convallaria majalis + I Querco-Fagetea Quercus petraea A 5 5 5 + 5 4 4 5 4 5 4 4 5 5 5 5 V Tilia tomentosa + I Tilia tomentosa Quercus petraea Acer campestre Crataegus monogyna Corylus avellana Tilia cordata Quercus petraea Cephalanthera longifolia Dactylis glomerata ssp. aschersoniana / D. glomerata Cruciata glabra Acer campestre Platanthera bifolia Tilia tomentosa Galium schultesii Other species Robinia pseudoacacia Juniperus communis Veronica chamaedrys Hypericum perforatum Rubus hirtus Viola alba Erigeron annuus Dianthus armeria Silene viridiflora Calystegia sepium Carex flacca Ajuga reptans Cardaminopsis arenosa Carex sp. Campanula sp. Clinopodium vulgare Campanula patula B C B + + + + + C + + + 2 + + + + + + + + + + + + + + + + + + + + + + + + + Number of releve 3 4 6 7 8 9 10 11 12 13 14 15 16 Gentiana asclepiadea Silene viscosa Verbena officinalis Mosses Polytrichum formosum Leucobryum glaucum Dicranella heteromalla Hypnum cupressiforme Atrichum undulatum Diphyscium foliosum Brachythecium velutinum Eurhynchium sp. Hypnum sp. 1 + + + 1 + 2 + 1 1 1 + + 1 + + + + + + + 1 + + 1 1 + + 1 + + + + + 1 + + + + + + + + + + + + + + + + + + + A - tree layer, B - shrub layer, C - layer of ground vegetation, D - layer of moss Table 2: Comparison of association Potentillo micranthae-Quercetum petraeae with related associations of order Quercetalia robori-petraeae. Tabela 2: Primerjava asocicije Potentillo micranthae-Quercetum petraeae s sorodnimi asocicijami reda Quercetalia robori-petraeae. Number of column Number of species* 1 2 3 5 Number of column 75 134 118 97 87 Number of species* 123 75 134 118 97 87 Number of releves 16 25 13 20 19 Number of releves 16 25 13 20 19 Percentage frequencies e Poa nemoralis 92 23 35 a Genista tinctoria B 94 46 60 32 Melica uniflora 88 46 25 Chamaecytisus hirsutus 81 23 30 c Symphytum tuberosum 80 8 35 c Galium sylvaticum C 81 23 90 11 Prunus avium 31 60 f Hypericum perforatum 69 20 16 f Galium mollugo 60 15 e Cephalanthera longifolia 63 8 30 e Galium schultesii 6 32 f Dianthus armeria 38 Pyrus pyraster 64 Erigeron annuus 44 Carex digitata 44 Viola alba 44 24 Crataegus monogyna 44 a Dicranella heteromalla D 50 Rosa canina 40 d Sorbus torminalis A 13 24 Hepatica nobilis 28 e Tilia tomentosa 6 8 f Luzula campestris 28 d Sorbus torminalis B 100 72 23 25 a Hieracium lachenalii 24 e Tilia tomentosa 38 60 Lembotropis nigricans B 44 38 35 47 d Potentilla micrantha C 75 68 30 d Chamaecytisus supinus 68 8 45 95 a Luzula forsteri 56 68 a Melampyrum pratense C 13 72 31 90 95 d Sorbus torminalis 25 76 Solidago virgaurea 44 23 55 74 e Tilia tomentosa 6 60 Hieracium sabaudum 20 23 45 89 b Festuca drymeia 100 28 100 15 Genista tinctoria ssp. ovata B 40 31 a Pteridium aquilinum 94 77 40 58 c Carex pilosa C 92 69 c Prunus avium A 16 f Ajuga reptans 6 44 38 e Pyrus pyraster 12 d Hypericum montanum 44 23 15 c Prunus avium B 60 15 20 e Hedera helix 36 23 5 e Crataegus monogyna 6 44 16 c Viola reichenbachiana 52 46 37 Pyrus pyraster 64 8 Mycelis muralis 13 36 54 Rosa canina 40 21 Galium odoratum 13 20 46 d Sorbus domestica 6 24 Dryopteris filix-mas C 13 54 10 e Ligustrum vulgare 24 Brachypodium sylvaticum 8 38 10 a Veronica officinalis C 56 84 23 21 Euphorbia amygdaloides 28 69 2 + + D V Number of column 1 2 3 Number of species* Number of releves 75 134 118 16 25 13 97 87 20 Sanicula europaea f Luzula pilosa b Cyclamen purpurascens c Carex sylvatica a Hieracium praecurrens f Circaea lutetiana Cruciata laevipes c Salvia glutinosa b Polystichum setiferum c Asarum europaeum f Viola hirta b Omphalodes verna f Senecio sylvaticus c Cephalanthera damasonium d Melittis melissophyllum Sorbus aria Tanacetum corymbosum e Cruciata glabra a Hieracium umbellatum Lathyrus linifolius c Euphorbia dulcis b Knautia drymeia f Achillea distans a Genista germanica f Vaccinium myrtillus d Convallaria majalis f Calamagrostis arundinacea Molinia caerulea ssp. arundinacea a Calluna vulgaris Deschampsia flexuosa c Prenanthes purpurea e Juniperus communis Genista pilosa f Frangula alnus e Anemone nemorosa a Potentilla erecta Chamaespartium sagittale d Silene italica Phyteuma zahlbruckneri Betonica officinalis ssp. serotina f Pleurozium schreberi a Quercetalia robori-petraeae Castanea sativa Castanea sativa Hieracium murorum Luzula luzuloides Hieracium racemosum Festuca heterophylla Serratula tinctoria Hieracium bauhinii Castanea sativa Polypodium vulgare 12 A C 19 25 12 16 23 25 23 30 25 15 70 26 23 65 16 23 40 35 15 35 25 30 30 74 35 42 23 50 53 8 55 58 8 25 26 15 25 95 35 89 45 32 15 10 89 42 15 37 23 42 68 32 42 37 26 47 A 38 4 15 40 26 B 94 20 31 85 68 C 38 100 62 70 79 94 100 46 100 89 94 88 38 95 100 88 76 69 80 63 6 16 15 30 5 6 12 . . . . 20 23 45 11 . 4 8 20 5 Number of column 1 2 3 4 5 Number of species* 75 134 118 97 87 Number of releves 16 25 13 20 19 Agrostis capillaris 21 b Aremonio-Fagion Ruscus hypoglossum C 25 16 38 Tamus communis 8 15 Helleborus odorus 20 c Fagetalia Fagus sylvatica A 56 92 38 30 16 Tilia platyphyllos 5 Fagus sylvatica B 81 96 46 65 53 Tilia cordata 6 20 23 Acer platanoides 16 15 10 Acer pseudoplatanus 16 23 30 Rosa arvensis 24 5 Tilia platyphyllos 15 Lathyrus vernus C 25 36 31 30 Cardamine bulbifera 19 24 31 15 Pulmonaria officinalis 6 4 31 10 Polygonatum multiflorum 28 15 20 16 Fagus sylvatica 25 96 10 Primula vulgaris 8 23 10 Moehringia trinervia 16 23 Scrophularia nodosa 15 15 Mercurialis perennis 23 5 Tilia cordata 20 Athyrium filix-femina 23 Acer pseudoplatanus 20 d Quercetalia pubescentis Fraxinus ornus A 31 48 31 15 Quercus cerris 60 63 Fraxinus ornus B 100 100 38 75 47 Cornus mas 6 28 15 Malus sylvestris 8 8 Quercus cerris 36 37 Euonymus verrucosus 20 Lathyrus niger C 19 20 62 70 63 Campanula persicifolia C 38 96 8 11 70 Fraxinus ornus 50 100 45 Vincetoxicum hirundinaria 8 15 Anthericum ramosum 24 11 Digitalis grandiflora 15 16 Quercus cerris 64 Cornus mas 28 Euonymus verrucosus 20 Carex montana 12 16 e Querco-Fagetea Quercus petraea A 100 100 100 100 100 Quercus petraea B 25 84 46 75 100 Acer campestre 13 16 8 Corylus avellana 6 30 37 B C D Number of column 1 2 3 4 5 Number of species* 75 134 118 97 87 Number of releves 16 25 13 20 19 Cornus sanguinea 4 8 Clematis vitalba 20 Platanthera bifolia C 6 28 15 20 16 Rubus hirtus 56 44 62 30 Dactylis glumerata ssp. aschersoniana / D. glomerata 38 80 54 40 Quercus petraea 81 100 90 21 Fragaria vesca 20 38 40 42 Acer campestre 6 16 Sedum telephium ssp. maximum 28 40 Epipactis helleborine 12 20 Fallopia dumetorum 20 Melittis melissophyllum ssp. carpatica 20 Neottia nidus-avis 20 f Other species Betula pendula I/II 4 23 11 Pinus nigra 4 Abies alba A 30 6 Picea abies 5 37 Pinus sylvestris 5 5 Robinia pseudacacia 23 Populus tremula 5 Robinia pseudacacia B 13 15 Pinus sylvestris 4 21 Populus tremula 8 16 Veronica chamaedrys C 75 20 23 45 37 Campanula patula 6 4 23 25 Number of column 1 2 3 4 5 Number of species* 75 134 118 97 87 Number of releves 16 25 13 20 19 Gentiana asclepiadea 6 23 20 11 Silene viridiflora 13 32 Clinopodium vulgare 13 36 Lysimachia punctata 4 23 Prunella vulgaris 4 31 Lychnis viscaria 36 25 Alliaria petiolata 4 10 Achillea millefolium 4 16 Trifolium montanum 4 11 Dianthus barbatus 15 20 Aposeris foetida 15 15 Pinus nigra 8 Glechoma hirsuta 23 Vicia sepium 20 Thymus serpyllum 26 Dianthus monspessulanus 26 Anthoxanthum odoratum 21 Mosses Atrichum undulatum D 38 47 Brachythecium velutinum 19 38 Dicranum scoparium 20 11 Diphyscium foliosum 38 Hypnum cupressiforme 44 20 95 Leucobryum glaucum 50 23 15 79 Polytrichum formosum 88 38 50 84 Cladonia pyxidata 16 Thuidium tamariscinum 21 A - tree layer, B - shrub layer, C - layer of ground vegetation, D - layer of moss a-f - sinsystematic affiliation Assocations: 1. Potentillo micranthae-Quercetum petraeae, Vukelic et al., Zrinska gora (Croatia) hoc loco 2. Luzulo forsteri-Quercetum petraeae, Kevey et Borhidi 1995, Mescek (Hungary) 3. Festuco drymeiae-Quercetum petraeae, Hruška Dell' Uomo 1974, Moslovačka gora (Croatia) 4. Hieracio racemosi-Quercetum petraeae, Vukelic 1991, NW Croatia 5. Melampyro vulgati-Quercetum petraeae "submediterraneum", Puncer et Zupančič 1979, Brkini (Slovenia) *The table excludes species that are represented in one column, up to 20% Table 3: Average Ellenberg index values for the selected ecological factors. Tabela 3: Povprečne indikatorske Ellenbergove vrednosti za izbrane ekološke faktorje. Breakdown Table of Descriptive Statistics N=93 (No missing data in dep. var. list). Association Light Temperature Continentality Means Moisture Soil Reaction Nutrients N Hr-Q 5,22 6,00 3,52 4,55 5,33 3,66 20 Lf-Q 4,91 6,10 3,57 4,42 6,20 4,07 25 Fd-Q 4,72 5,76 3,44 4,86 5,97 4,70 13 Pm-Q 5,21 6,30 3,41 4,49 5,83 3,84 16 Mp-Q 5,73 5,87 3,66 4,37 4,27 3,05 19 All Groups 5,17 6,02 3,53 4,51 5,52 3,82 93