Components of beta diversity in coastal stream fishes of "Baixada Santista" (SP)

Abstract

The beta diversity in fluvial systems is influenced by habitat availability, species interactions and organism dispersion. The ability to predict and mitigate the effects of anthropogenic changes in these systems depends on the knowledge of which processes are important for the maintenance of diversity at local and regional scales. Due to dendritic structure of stream basins, it is expected for example, that the dispersion intensity is greater downstream, while local habitats availability is most important upstream. This project aims to analyze the influence of environmental heterogeneity and spatial structure on patterns of beta diversity of fishes in streams of "Baixada Santista" (SP). Components of beta diversity (species addition and turnover) will be analyzed at multiple spatial scales (within and between basins). The environments will be described by local variables related to the habitat size and ecosystem function, and regional variables related to spatial structure of the stream basins. Results will quantify the relative importance of local and regional factors on the taxonomic and functional diversity, aiming to recommend conservation actions to streams of "Baixada Santista". (AU)