ABSTRACT
Scientific interest in alpine flora has increasingly focused on diversity patterns. The predicted development of vegetation in treeline ecotones and in alpine zones has to be confirmed by long-term field observations. Species richness, as the most widespread indicator of diversity, was already being suggested 100 years ago, e.g. for the alpine arc in Europe. Correlations were determined between environmental variables and species richness. Stepwise multiple regression was performed to determine best-fitting predictor equations of species richness, with p = 0.05 as the selection and deselection criteria. Mapping areas with reduced species richness were generally located at the two front ranges of the alpine arc. The species-area relationship indicated that species richness increased with increasing area size, but regression curves for small and large mapping areas differed considerably in their slopes. An evaluation of the factors determining species richness is important in assessing the possible effects of climate change in alpine regions.
