Significance of different types of meadow edges for plant diversity in the Swiss Alps

This study examined whether meadow edges have higher plant species richness and evenness than the centre of meadows and whether these effects differ between management intensity and altitudes. Vascular plant species were recorded in three different regions of the Swiss Alps using a paired meadow-edge sampling approach, and three types of meadow edges were considered: roadsides and north- and south-facing forest borders.Almost 50% of all recorded plant species were found exclusively in the edges, whereas only few species were detected exclusively in the meadow centres. Generally higher species richness and evenness were observed in north- and south-facing forest borders than in meadow centres. Plant species richness was also higher at roadsides than in the centre of meadows at high altitudes, but did not differ between the two habitat types at low altitudes. Most relevant for plant conservation, richness of endangered species (regionally protected or Red list species) was significantly higher in almost all edge structures than in the adjacent meadows. Richness of all recorded plant species as well as the number of endangered species was substantially higher under extensive rather than intensive management.In conclusion, different types of meadow edges are shown to be important habitats for plant species diversity and conservation in Swiss alpine grasslands. Therefore, meadow edges should be maintained by specific agro-ecological measures, which could also positively affect fauna diversity.

► Edges have higher plant species richness and species evenness than meadow centres.
► Positive edge effects on plant diversity are more pronounced at higher altitude.
► A proportion of plant species that are indicators of edge communities are endangered at a regional level in Switzerland.