Abstract Understanding the response of macroinvertebrate communities and diversity to seasonal hydrological changes is crucial for maintaining biodiversity, ecosystem functioning, and services. This study was a systematic examination of the seasonal dynamics of aquatic environments, macroinvertebrate multidimensional diversity, and community structure across three hydrological seasons (normal, dry, and wet) in a karst stream in southwest China. The dry season exhibited the highest taxonomic richness (16.7 ± 11.1) but lower taxonomic–phylogenetic diversity (222, median), alongside minimal evenness (0.65 ± 0.19). The wet season had higher richness (11.6 ± 7.6), the greatest phylogenetic diversity (297), and peak evenness (0.82 ± 0.12). The normal season showed the lowest richness (6.7 ± 4.8) and phylogenetic diversity (122), with moderate evenness (0.78 ± 0.2). Dry season communities were taxonomically uneven, dominated by Diptera (78.0% abundance), primarily Chironomidae and Simuliidae (75.4%), with Simulium and Chironomus alone composing 45%. Seasonal hydrological disturbances were the main drivers of diversity and structural changes. Increased turbidity was correlated positively with declines in richness (R2 = 0.24, P = .009), abundance (R2 = 0.53, P = .001), and phylogenetic diversity (R2 = 0.12, P = .078), but negatively with evenness (R2 = 0.30, P = .006). Environmental disturbances enhanced biodiversity by altering species interactions and community organization, with the net effect depending on habitat conditions.
Liu et al. (Wed,) studied this question.