invited Talk, JASM - Joint Aquatic Science Meeting 2014, Portland: 2014-05-18 - 2014-05-23
Abstract:
Understanding the ecological effects of anthropogenic shifts in environmental settings is a major objective of current ecological research. In crenal habitats, anthropogenic shifts in catchment biogeochemistry directly affect plant community composition, which allows for a sound bio-monitoring of such effects. To understand the link between biotic response and abiotic shifts, we studied plant community composition and hydrochemistry of 238 helocrenic springs from 5 mountainous regions in Central Germany. Spatial patterns of dominance relations and compositional community turnover were explained by using realized niche space and generalized dissimilarity modelling based on spring hydrochemistry. We detected three dominant plant species with high local abundance and spatial frequency (high commonness), reflecting the acidity and temperature regime of the studied springs. Commonness of these species was negatively related to their realized niche breadth. Spatial turnover of community composition was explained best by water temperature and concentration of elements related to acidification (Al, Cd, Ca and Mg). Thus, temperature and acidity regime can be assumed to be the major driver of dominance and beta-diversity patterns in helocrenic springs of Central Germany’s lower mountain ranges.