Impact of Socioeconomic Development on the Aquatic Biodiversity: Evidence from Sedimentary Microbial Communities in Beiluo River, China

Socioeconomic development is known as the main exogenous factor threatening the global river biodiversity. While the sediment microbial communities play a crucial role in biogeochemical cycling and in maintaining the ecological balance of rivers, the impact of socioeconomic development on the microbial biodiversity and ecological health remains undetermined. Herein, we established a holistic approach to assess the ecological health of sediment environments along the Beiluo River, China. This approach integrated sediment quality factors and microbial biodiversity datasets into ecological health assessments while considering their intrinsic relationship with socioeconomic development, which employs a comprehensive set of 22 indicators, covering social activities and agricultural practice. The findings suggested that socioeconomic activities deteriorated the sediment quality, as evidenced by abnormal increases in key indicators (electric conductivity (EC), dissolved organic carbon (DOC), NH₄⁺-N, and NH₃⁻-N). For example, DOC showed a significant positive correlation with per capita GDP (|r| = 0.61, P < 0.05), indicating that intensified socioeconomic activities contributed to organic matter accumulation in sediments. The decline in the richness of prokaryotes (Proteobacteria, Actinobacteriota, and Chloroflexi) and eukaryotes (Bacillariophyta and Cercozoa) was associated with agricultural pollution, which intensified environmental stress and impaired microbial survival in the sediments, with microbial diversity indices (Chao1 and Shannon) decreasing by 58.77% and 79.70%, respectively. Overall, socioeconomic development influences sediment microbial communities primarily through cascading effects driven by nutrient enrichment and associated changes in sediment quality.