Changes in floristic composition of the mountain pasture sward after the abandonment of sheep grazing

摘要

Grassland ecosystems play many important functions in the environment, e.g. in shaping landscape, which is particularly visible in the richness of species. Abandonment can lead to impoverished floristic diversity. The aim of our study was to compare floristic composition and species diversity in mountain pastures, both grazed and abandoned. The study was located in the Jaworzyna Krynicka Range, at 600 and 750 m a.s.l. It was divided into two parts, the first one was carried out in 2005 in cultivatedpastures and it was a starting point for the comparison of such pastures after five years (in 2010), during which part was continuously utilized and some was abandoned, due to the decreased number of sheep. Five years after sheep grazing stopped the species richness of vascular plants had decreased, and dominance of a few expansive species was visible; e.g. Deschampsia caespitosa at 750 m a.s.l, and Juncus effuses and Mentha longifolia at some lower locations. Maintaining of utilization by grazing of such habitats has affected them positively, by sustaining a greater number of species.