Partitioning multiple facets of beta diversity in a tropical stream macroalgal metacommunity

Aim: We evaluated different dimensions of beta diversity (taxonomic, phylogenetic, and functional), and its components (spatial turnover and nestedness), of a stream macroalgal metacommunity, as well as the effect of local environmental variables, types of biome, and spatial factors on these dimensions and components.

Location: Ten natural areas of southern Brazil, covering the main biomes represented in the region.

Methods: We analyzed a data set collected in 105 stream segments using a dissimilarity partitioning approach to decompose total beta diversity (beta.SOR – multisite dissimilarity; beta.sor – pairwise dissimilarity) into spatial turnover (beta.SIM; beta.sim) and nestedness (beta.SNE; beta.sne) components. Furthermore, we assessed the effects of local environmental variables, types of biome, and spatial factors on beta diversity components by performing distance-based redundancy analysis (db-RDA), and its partial version (db-pRDA). Taxonomic data were tabulated consider...