Uncovering patterns and drivers of macroinvertebrate ecological uniqueness for conservation planning in riverine tributaries of Thousand Islands Lake, China

Beta diversity has emerged as a crucial factor in conservation efforts, particularly through the measurement of local contributions to beta diversity (LCBD), which is increasingly recognized for their value in conservation planning. This study investigated the distribution, interrelationships, and determinants of taxonomic, functional, and phylogenetic LCBD from 147 sampling sites in the Thousand Islands Lake catchment in China, and explored the taxa that contribute most to beta diversity (SCBD) in the region. By adopting distance-based methods, we applied a framework combining biotic and abiotic uniqueness (local contributions to environmental heterogeneity, LCEH) based on macroinvertebrate and environmental data to enhance ecological conservation and restoration strategies within the region. Our findings indicate: (1) significant correlations between biotic uniqueness and insignificant correlations between biotic and abiotic uniqueness emphasize the importance of simultaneously considering abiotic and biotic uniqueness; (2) key physicochemical factors such as pH, nitrogen-to-phosphorus ratio (NPR), and stream width significantly influence LCBD; (3) a significant negative correlation between biotic uniqueness and species richness, suggesting that areas of high uniqueness may require more targeted restoration efforts; (4) protecting approximately 35–50% of the sampling sites preserves about 60% of the area’s ecological uniqueness. This integrative approach promises to guide future conservation and restoration initiatives effectively by combining biological community data with stable environmental characteristics. Continued research is essential to further explore the interplay between environmental factors and LCBD, and to integrate this approach with metacommunity theory across diverse ecological and geographical contexts.