The distribution of arctic-alpine elements within high-altitude vegetation of the Western Carpathians in relation to environmental factors, life forms and phytogeography
Šibíková, Ivana; Šibík, Jozef; Hájek, Michal; Kliment, Ján
This study presents an analysis of phytosociological relevés together with data on phytogeographical elements, life forms and Ellenberg's indicator values in the alpine flora of the Western Carpathians. We examined the frequency of arctic-alpine taxa in individual vegetation types and their distribution within the Western Carpathians, as well as the comparison to the distribution of Carpathian and West-Carpathian endemics. The combination of arctic-alpine and endemic Carpathian and West-Carpathian elements leads to new insights of spatial patterns and chorological aspects in vegetation. The data sets of 5,030 phytosociological relevés containing at least one arcticalpine taxon, and of 3,510 relevés from 14 alliances in which at least 25% of the total number of relevés contained at least two arctic-alpine taxa, were used for individual analyses: the main gradients in floristic composition were analysed by Detrended Correspondence Analysis; the frequency of arctic-alpine species was used as an attribute data in DCA Attribute Data Analysis; the multiple comparisons were performed and the box and whisker plots were constructed. We confirmed the hypothesis that more arctic-alpine taxa occur in plant communities of the Carici rupestris-Kobresietea as compared to other vegetation types in the Western Carpathians and to other phytogeographical elements in the West Carpathian flora. In addition, the occurrence of arctic-alpine species was significantly correlated not only with the European high-mountain element, but also with the occurrence of the Carpathian and/ or West Carpathian endemic taxa. One possible explanation relates to the theory of an island phenomenon in the highest mountains. The diverse conditions of the mountains gave rise to the formation of refuges for relic taxa, and in addition, depending on the plasticity of individual taxa, the same habitats also provided suitable conditions for speciation and hence became centres of endemism.