Macroecological drivers of vascular plant species composition in semi-natural grasslands: A regional study from Lower Silesia (Poland).

In agricultural landscapes of Europe, species-rich semi-natural grasslands provide numerous ecosystem services, such as forage production, ground and surface water regulation, and carbon sequestration. In the face of the declining area of grasslands, information about the macroecological drivers of grasslands diversity is an important element of studies on their ecology and management. Here, we tested the effect of factors representing environmental gradients, landscape structure, human pressure, habitat continuity in time, and spatial structure on species composition of vascular plants in semi-natural grasslands. The analysis was performed using a multivariate approach for 689 vegetation plots distributed across ~20,000 km in the Lower Silesia region (Poland, Central Europe). We found that species composition was significantly influenced by factors representing all studied groups. The most influential factors were temperature, long-term habitat continuity, and topography. Moreover, we captured the correlation between habitat conditions and habitat continuity. Old grasslands (existing since the 1940s) usually occurred in wet habitats, and medium grasslands (existing since the 1980s) existed in highlands in most cases. We highlighted the potential of freely available environmental databases, as well as historical topographic maps, in the exploration of patterns of species composition at a large spatial extent. The result show also the usefulness of vegetation databases in recognition of grassland complexes contributing the regional biodiversity.