Impact of shrub cover and wild ungulate browsing on the vegetation of restored mountain hay meadows

Grasslands of middle mountain regions are among the most diverse habitats of the Carpathian Basin, but they are threatened by spontaneous succession leading to woody encroachment. It is a high priority of nature conservation to preserve these diverse habitats by suppressing the woody encroachment and to create new open habitat patches by scrub removal. The main goal of this study was to investigate the effect of shrub cover on plant species composition and vegetation in terms of relative ecological indica-tor values in semi-natural grassland patches. We also aimed at studying the wild browsers’ preference for woody species, which potentially plays a role in shrub encroachment. The study was conducted in the Mátra mountains, North-Hungary, where three study sites were selected within the Fagetalia belt: two sites recently restored by scrub removal with different post-restoration management and a semi-natural grassland as a control site. All of the sites were available for wild ungulate grazing. At each study site, vegetation and browsing data were recorded at 50 sampling points for which we used circu-lar plots with a radius of 1.13 m (4 m2). The highest shrub cover was found in the clearing that was grazed only by wild ungulates. The linear regression analysis showed that shrub cover significantly increased the abundance-weighted nutrient (NB) and water (WB) scores and decreased the naturalness value (SBT). Moreover, we found that an increase of shrub cover significantly decreased cover and species richness of grassland specialists, but increased weed cover. Most of the woody species were browsed in relation to their abundance except Rubus and Acer species, which were non-preferred. Our results highlight that shrub encroachment has a negative effect on semi-natural grasslands and that beside wild ungulate browsing additional management is needed to preserve these diverse habitats.