Climate change leads to elevational shift of alpine plants. This favours the increase of warmth-demanding species on the cost of cold-adapted species, which may subsequentially lose suitable habitats. This process is known as thermophilization. First signals of thermophilization have already been found after a short study period (2001-2008) across 18 European mountain regions. As a further consequences of species range shifts, we expect increasing signals of biotic homogenization, because upwards moving species from low elevations usually have wider distribution ranges than high-mountain species. In this study, we will use data of 1-m² permanent plots of the expanded European GLORIA* monitoring network (with 35 regions), with extended time-series (up to >20 years). The study sites are distributed over the main European biomes (Mediterranean, humid-temperate, boreal, arctic), including more than 1200 vascular plant species. We will analyse if the previously observed directional species turnover is consistent across Europe and has changed in magnitude and velocity. Further, we will assess if thermophilization has already caused a measurable biotic homogenization, i. e., composition of vegetation in plot, summits and region have become more similar to each other.
This study will be based on many contributors from GLORIA-Europe and of the Microclim project, to be included in the authorship of the publication.
* Global Observation Research Initiative in Alpine Environments