Neophyte invasions in European grasslands

Questions The human-related spread of alien plants has serious environmental and socioeconomic impacts. Therefore, it is important to know which habitats are most threatened by invasion why. We studied a wide range European grasslands assess: (a) species the successful invaders in grasslands; (b) how levels differ across regions (countries or their parts) biogeographical regions; (c) habitat types invaded. Location Europe. Methods selected 97,411 grassland vegetation plots from Vegetation Archive (EVA) assigned native status each 8,212 vascular plant found these plots. considered only neophytes (alien introduced after 1500 AD), we further divided according origin. compared using relative neophyte richness pool, cover per plot, percentages invaded among habitats. Results Only 536 species, representing 6.5% all were classified as neophytes. These mostly therophytes hemicryptophytes with low specificity. Most them present very few plots, while three recorded more than 1% (Onobrychis viciifolia, Erigeron annuus canadensis). Although generally low, Boreal Continental regions. When considering non-European neophytes, Pannonian region was Among different habitats, sandy invaded, alpine oromediterranean least Conclusions In general, natural semi-natural have relatively invasions human-made alluvial forests, well on other continents. typical invading broad ecological niches.