关键词: 再生水补水; 细菌群落结构; 底泥; 重金属; 西乡河;

Abstract: To clarify the influence of reclaimed water replenishment on the bacterial community structure of river sediments, the reclaimed water replenishment of the Xixiang River in Shenzhen City was taken as the research object, based on the analysis of the physical and chemical indicators of 8 sediment samples in the river channel, the Illumina high-throughput sequencing technology was used to explore the spatial difference in the bacterial community structure of the sediment after the reclaimed water in the river channel and its impact on environmental factors.In addition, the formation reasons for the spatial difference of the bacterial community structure are analyzed by redundancy analysis method.The analysis results show the sediment in the middle and lower reaches of the Xixiang River contains a variety of pollutants, and the heavy metal pollution is more serious in the middle reaches; there are significant spatial differences in the bacterial community structure and diversity in river sediments, and a high diversity of microorganisms in the bottom mud near the water replenishment port; the dominant bacteria in the river sediments are Thiobacillus,Bacteroides,Desulfatiglans,Desulfococcus,Desulfuromonas,Desulfomicrobicum,and denitrifying bacteria(Dechloromonas,Ferritrophicum),which accounts for more than 70% of the cloned library; Nitrogen, phosphorus, organics, and heavy metals such as Cu and Fe in the reclaimed water are responsible for the diversity and abundance of denitrifying bacteria and desulfurizing bacteria in the sediments near the water intake, it has a significant effect on the degree, but it has little effect on microorganisms in the sediments of the Pearl River Estuary.

Key words: reclaimed water replenishment; bacterial community structure; sediment; heavy metal; Xixiang River;