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Knowledge about relationships between specialization degree of species, i.e. the width of their realized niche and functional traits, may have important implications for the assessment of future population developments under environmental change. In this study, we used a recently introduced method to calculate ecological niche widths of plant species in mixed broad-leaved deciduous forests and to investigate the dependence between niche widths of plants and their functional traits and Ellenberg indicator values. The research is based on a dataset of 4556 phytosociological releves of mixed broad-leaved deciduous forests in Slovenia. We calculated theta indices for 326 species, which ranks them along a continuous gradient of habitat specialization. For 272 species, we compiled 26 functional traits and Ellenberg indicator values. We found some significant correlations between theta indices of species and their functional traits and Ellenberg indicator values; habitat specialists thrive primarily on the highest altitudes, on colder, dry sites and achieve the age of first flowering later than generalists. They also have smaller seed diameter, lower leaf dry matter content, lower mean canopy height and bigger specific leaf area than generalists. Two species groups, chamaephytes and spring green species, are particularly characterized as specialist species. The added value of our work is in complementing the knowledge about the niche differentiating along different environmental gradients and species coexistence in mixed broad-leaved deciduous forests.

Relationships between environmental factors and plant species-richness as well as the composition of plant species in wet grasslands from the order Molinietalia caeruleae were studied with a view to quantifying the relative contribution of different abiotic factors, such as soil chemical parameters, climatic conditions and human impact to diversity of vascular plants and floristic composition. Data and soil samples were collected from 88 plots across Slovenia from regions at the eastern edge of the Po plain, karstic and pre-Alpine mountain regions and the western part of the Pannonian plain, which are classified to sub-Mediterranean, Dinnaric, pre-Alpine and sub-Pannonian phytogeographic areas. Plant diversity was positively correlated with the content of exchangeable Ca2+ in soil and the amount of annual precipitation, while significant negative correlation was calculated in case of the plant-available phosphorous content and altitude. Moreover, plant species richness was also negatively correlated with altitude. Among the groups of environmental factors the group of soil factors revealed the strongest correlation with species richness, followed by climatic and topographic group. The order of these groups was the same in the explanation of species composition. Variance of plant species composition was best explained with altitude, soil pH, geographical gradient, frequency of flooding, mean annual temperature, date of mowing, humidity, annual amount of precipitation as well as with the content of plant-available phosphorous, total nitrogen, exchangeable Mg2+ and Ca2+ in the soil.

Floristic differentiation of the oriental beech (Fagus orientalis Lipsky) forests in Turkey and Bulgaria was investigated and the role of geographical and topographical factors in this differentiation was assessed. After geographical and ecological stratification of the available 922 releves, 288 remained. Classification, by applying cluster analysis, resulted in seven vegetation units defined by species composition which represent the geographical and ecological variation of Fagus orientalis forests. DCA ordination was applied to these units by passively projecting their chorological structure, as supplementary variables. For more detailed interpretation of vegetation types with similar geographic distribution patterns, PCA was applied by passively projecting the chorological elements, life-forms and topographical factors as supplementary variables. Seven vegetation units representing the geographical and ecological variety of Fagus orientalis forests were described. Four vegetation units represent the core area of Fagus orientalis distribution on the western and middle coast of the Black Sea region (Euxine region); the remaining three types represent the distribution in the eastern Black Sea region (Colchic region), the distribution in western and southern Anatolia under the influence of the Mediterranean climate and the distribution in the transitional zone from the Euxine region to the continental parts of Inner Anatolia, respectively. The four vegetation types in Euxine region reflect the decreasing effect of Black Sea towards Inner Anatolia, as well as altitudinal differences, except the forest type representing forests on calcareous sites. The other three vegetation units represent ravine, lowland to montane and altimontane forests in Euxine region. Fagus orientalis forests could be distinguished by their floristic composition, their chorological elements and life-forms spectra, which reflect a geographical and ecological gradients.

The work deals with vegetation zonation in temporary ponds within cold holes in the Western Taurus mountain chain. There are two main factors that cause differentiation within the studied vegetation: one relates to the microtopography, the other to altitude. In the bottom of temporary ponds, marsh vegetation of Ranunculo argyrei-Tanacetea argentei (Sedo nani-Convolvuletalia galactici) appears (an endemic class vicariant to Scheuchzerio-Caricetea fuscae); in the intermediate zone, the vegetation is dominated by therophytes of Stellarietea mediae (Thero-Brometalia) and in the upper part, there is vegetation of hygrophilous grassland communities of Molinio-Arrhenatheretea (Potentillo-Polygonetalia). This zonation of communities can be found at lower altitudes (up to 1600 m); whereas at higher altitudes, the intermediate zone dominated by therophytes gradually disappears and then also the hygrophilous grasslands. The work also provides a description of new syntaxa, to wit: Ranunculo argyrei-Tanacetea argentei, Sedo nani-Convolvuletalia galactici, Rorippo aureae-Eleocharidion quinqueflorae, Sedo nani-Ranunculetum argyrei, Trifolio caudati-Hordeion geniculati, Taeniathero caput-medusae-Hordeetum geniculati, Alopecuro vaginati-Trifolion resupinati and Ornithogalo lanceolati-Elymetum repentis.

The influence of water regime on the zonation of wetland communities, distribution patterns of plant species, ecological strategies and biodiversity, was studied in this work. Vegetation of the herbaceous wetland was sampled along a transect, in accordance with the standard central European method. Water level was also measured. The changes in plant species composition, plant functional types (ecological strategies, life forms) and diversity were studied. Classification of vegetation releves enabled the definition of five grassland communities. The same pattern remained in DCA ordination also when the species matrix was replaced with a matrix of ecological strategies. Releves were always segregated into distinct plant communities and distributed along the moisture gradient in the same way. Biodiversity is strongly negatively correlated with moisture–it is decreasing with decreasing ground level. Plant ecological strategy types (C-S-R) change significantly along the transect as well. In communities thriving on the driest sites (Triseto-Centaureetum), there are three times more C- than C-S-strategists, while in the wettest sites (Caricetum elatae) C-S-strategists predominate over C-strategists by almost two times. At the same time R-and C-R-strategists, as well as therophytes, which are present in drier sites almost disappear in the wettest sites. We show that the moisture gradient essentially influences the distribution pattern of plant communities, species diversity, and manifestation of certain ecological strategy types.

The main objective of this study was to examine the relationships between wet meadow plant communities of Molinon alliance and their environmental conditions in Slovenia. The ecology of these communities was analysed in detail. The study provides the data on the vegetation and environmental parameters, the significance of parameters for the plant species composition, most important environmental gradients and differences between plant communities. In all plots the vegetation was recorded and soil parameters were analysed (pH, plant-available P and K, Nt, organic C, C/N ratio, exchangeable Ca2+, Mg2+, K+, Na+, H+, electrical conductivity, base saturation). Other conditions were also considered (e.g., mean annual temperature and precipitation, humidity index, mean Ellenberg moisture and nutrient value) to test possible correlations as well. Vegetation was classified by means of multivariate cluster analysis, while vegetation-site relationships were examined with direct gradient analysis (CCA). Six associations from the Molinon alliance (Selino-Molinietum, Plantagini altissimae-Molinietum, Carici davallianae-Molinietum, Gentiano-Molinietum litoralis, Junco conglomerati-Betonicetum and Sanguisorbo-Festucetum commutatae) were identified and analysed. Soil reaction was identified as most significant environmental parameter explaining the variation of the studied vegetation. There are several statistically significant differences in site conditions between the communities (pH, moisture, nutrient status, Ca2+). The studied associations represent clearly defined ecological units.

This paper summarises present knowledge of the natural saum vegetation (Trifolio-Geranietea: Trifolion medii, Geranienion andDictamno-Ferulagenion) in Slovenia. The alliance ofGeranion sanguinei was subdivided into theGeranienio (primarily of Central European distribution) and SubmediterreanDictamno-Ferulagenion. Several new syntaxa (Scorzonero villosae-Trifolietum alpestris, Cirsio-Clematidetum rectae andOrigano-Cnidietum silaifolii) were described within theDictamno-Ferulagenion.