面源污染诱导嘉陵江沉积物中细菌群落结构与功能异变

通过分析嘉陵江沉积物中细菌群落多样性变化，揭示面源污染对嘉陵江水环境的影响，为嘉陵江流域的环境保护与资源利用提供依据.于2020年12月在嘉陵江面源污染型支流的入江口采集非面源污染样品、面源污染样品和面源污染干扰样品这3种类型沉积物.利用高通量测序技术分析嘉陵江不同类型沉积物中细菌群落结构、多样性及功能类型.结果表明：嘉陵江不同类型沉积物的理化性质和细菌群落多样性均存在显著性差异(P<0.05).沉积物细菌的优势菌群为变形菌门，其次为蓝藻菌门、绿弯菌门、放线菌门和酸杆菌门(相对丰度>1%),面源污染导致蓝藻菌门显著减少，促进酸杆菌门显著增加(P<0.05).水解氮、总氮、有机碳和pH值为嘉陵江沉积物细菌群落变化的主要影响因子.沉积物细菌群落主要涉及到了细胞过程、环境信息处理、遗传信息处理和新陈代谢4类一级代谢功能，二级功能在全局及概要图、碳水化合物代谢、氨基酸代谢和能量代谢等18类基因功能方面表现活跃，面源污染诱导了脂质代谢、外源生物降解与代谢、折叠、分类和降解和膜运输等主要二级功能发生异变(P<0.05).综上所述，面源污染造成沉积物细菌群落结构与功能发生变化...

Non-point Source Pollution (NPSP) Induces Structural and Functional Variation in Bacterial Communities in Sediments of Jialing River

This study aimed to provide evidence for environmental protection and resource utilization in the Jialing River basin through analysis of bacterial community diversity variation in Jialing River sediments and to reveal the impact of non-point source pollution on the water environment of the Jialing River. In December 2021, three types of sediment samples (non-contaminated samples, non-point source pollution samples, and non-point source pollution effects samples) were collected at the estuary of the non-point source pollution tributary of the Jialing River. High-throughput sequencing technology was used to analyze the bacterial community structure, diversity, and functional types in different types of sediments in the Jialing River. The results showed that there were significant differences in the physical and chemical properties and bacterial community diversity in different types of sediments in the Jialing River (P<0.05). The dominant phylum of sediment bacteria was the Proteobacteria, followed by the Cyanobacteria, Chloroflexi, Actinobacteriota, and Acidobacteriota (relative abundance>1%). Non-point source pollution caused a significant decrease in Cyanobacteria and a significant increase in Acidobacteria (P<0.05). Available nitrogen, total nitrogen, organic carbon, and pH were the main influencing factors of bacterial community changes in Jialing River sediments. The bacterial community in sediments mainly involved four primary metabolic pathways:cellular processes, environmental information processing, genetic information processing, and metabolism. The secondary metabolic pathways were active in 18 functional genes such as global and overview maps, carbohydrate metabolism, amino acid metabolism, and energy metabolism. Non-point source pollution induced significant variation in the main secondary metabolic pathways such as lipid metabolism, xenobiotics biodegradation and metabolism, folding, sorting and degradation, and membrane transport (P<0.05). Hence, non-point source pollution caused structural and functional variation in bacterial communities in the sediments of the Jialing River and destroyed the stability of the Jialing River basin ecosystem.