Interactive effects of rabbit grazing and environmental factors on plant species-richness on dunes of Norderney

Abstract

On the German island Norderney rabbit grazing effects on vegetation, soil and microclimate were investigated with exclosures in different dune vegetation. Differences in species composition between grazed and ungrazed plots increased with grazing activity. A decline in growth height resulted in higher light availability and temperature on the grazed sites. One of the most visible effects was the decline in flowering plants. Most grazing effects varied between habitat types. Grey dunes were distinctly affected by rabbit grazing. In relation to the habitat type, life forms were differently affected: in closed vegetation, rabbit activities further open patches, resulting in more therophytes. In contrast, in open vegetation rabbit activities were too strong and following sand dynamics too high for many therophytes. In general, grazing diversified habitats, slightly supported the total species-richness, and enhanced the heterogeneity of species composition. Highest speciesrichness in total and of herbs was reached at intermediate levels of grazing pressure. The study is in line that highest species-diversity will be found at intermediate levels of disturbance and environmental stress and that grazing effects vary with the habitat type.

Biogeographic variability of coastal perennial grasslands at the European scale

“…Brullo, Giusso del Caldo, Siracusa, & Spampinato, ; Colasse & Delassus, ; Gamper, Filesi, Buffa, & Sburlino, ), using the Braun‐Blanquet approach (Dengler, Chytrý, & Ewald, ; Westhoff & van der Maarel, ), or on ecology, management and conservation strategies (e.g. Del Vecchio, Slaviero, Fantinato, & Buffa, ; Isermann, Koehler, & Mühl, ; Provoost et al., ). However, despite their evident diversity, no comparative studies, analysing the variability of coastal perennial grasslands across their European range have been carried out yet.…”

The use of plant community attributes to detect habitat quality in coastal environments

“…TD are harsh environments which favour drought tolerant plants. However, compared to the FD zone, TD are less exposed to salt winds, coastal erosion and sand burial, and so are more stable, supporting the highest number of plant species of the dry dune series ( Isermann et al 2010 ). Total percentage cover values are higher than in FD, often reaching 100%.…”