Regional and local impact on species diversity - from pattern to processes

摘要: The impact of regional factors (such as speciation or dispersal) on the species richness in local communities (SL) has received increasing attention. A prominent method to infer is comparison assemblages with total number region (SR). Linear relations between SR and SL have been interpreted an indication strong influence weak interactions within communities. We propose that two aspects bias outcome such comparisons: (1) spatial scale sampling, (2) body size organisms. area reflects scales ecological interactions, whereas ratio inherent moment autocorrelation. proposed relation based high dispersal abundance small predict strongest linearity for large organisms, areas (less important interactions) sampling designs where habitat covers a proportion (more autocorrelation). conducted meta-analysis 63 obtained from literature. As predicted, relationship increased area. In contrast, neither organisms nor itself was significantly related SR. This indicated played minor role shape plots, which instead mainly influenced by design. found studies published so far were highly biased towards larger similarity prevalence linear relationships may thus be artefact plots are not suitable tool strength interactions.