Understanding the relative roles of local environmental, geo-climatic and spatial factors for taxonomic, functional and phylogenetic β -diversity of stream fishes in a large basin, Northeast China.

The primary objective of this study was to determine the relative roles of local environmental ( Local ), geo-climatic ( Geo ), and spatial ( Spatial ) factors to taxonomic, functional, and phylogenetic β -diversity of stream fish in a large basin in Northeast China. We quantified the current biodiversity patterns of fish communities in the Hun-Tai River using β -diversity. We assessed (i) corresponding contributions of turnover and nestedness within the taxonomic, functional, and phylogenetic β -diversity of fishes; (ii) correlations among β -diversity facets (i.e., taxonomic, functional, and phylogenetic facets); (iii) relative contributions of Local , Geo , and Spatial factors to β -diversity. We collected fish communities from 171 sampling sites. Mantel tests were used to examine the correlation of three facets of β -diversity and their components (i.e., total, nestedness, and turnover). Distance-based redundancy analysis and variation partitioning assess the relative contributions of Local , Geo , and Spatial factors to β -diversity. We found that turnover is the main driving mechanism for β -diversity in fish. Among the facets of β -diversity, taxonomic and phylogenetic facets have strong ecological information association.  Spatial factors have a general contribution to various facets of β -diversity and its components. From aspects of fish β -diversity conservation, connectivity and habitat heterogeneity need to be maintained in the entire aquatic environment. In addition, protecting taxonomic β -diversity is helpful for maintaining phylogenetic β -diversity.