Plant diversity across small-scale boundaries

Questions: Habitat islands are often characterized by the presence of more or less sharp boundaries to adjacent matrix habitats. However, knowledge on boundaries of natural habitat islands is scarce, especially regarding patterns of beta diversity and its two underlying components: species turnover and nestedness. We therefore aim to quantify the effects of fine-scaled and sharp boundaries of quartz islands (quartz-gravel covered soils) on the different components of plant beta diversity and how they are linked to different soil environmental drivers. Location: Knersvlakte, Western Cape, South Africa. Methods: We sampled plant species richness in 56 fine-scale transects of 6 × 1 m² plots across eight different boundary types (four quartz island – matrix, four between habitats on quartz islands). Soil depth and chemistry (pH, electrical conductivity) were analyzed for each 1 m² plot. Differences in the two beta diversity components (turnover and nestedness) for each boundary type w...