Environmental drivers and diversity of open plant communities in grassland and wetland mosaics in coastal southern Brazil

Small-scale biotic and abiotic variables can influence species composition at a given location, and environmental heterogeneity across sites can lead to the development of vegetation mosaics. Understanding how plant communities are influenced by these variables is fundamental to devise adequate management strategies for biodiversity conservation and management. Here, we evaluated the plant species composition and environmental drivers of different open environments of Lagoa do Peixe National Park in subtropical southern Brazil. We used cluster analysis (UPGMA) to classify the sites into major vegetation types and verified the relationship of these groups with environmental variables through redundancy analysis (RDA). We conducted indicator species analysis for each group of sites. We found seven groups of sites with distinct species composition: marsh, shrub grassland, wet lowland, grazed grassland, dune vegetation, dune grassland and degraded wet lowland. Variables related to moisture, vegetation height and soil cover, as well as indicators of cattle management and the presence of invasive pine, were the main drivers of changes in species composition among the different groups. At the study site, grazing management contributes to biodiversity conservation, maintaining open habitat with typical species. Understanding open landscapes as compatible with and dependent on management is essential for the conservation of the typical species of these environments.