LAUSR

Abstract 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.