Spatial distribution of bacterial communities driven by multiple environmental factors in sediment of brackish channel catfish ponds in Eastern China

Sediment bacteria are crucial for maintaining water quality, preventing disease, and cycling nutrients in aquaculture ponds. In the present study, a total of 42 sediment samples were collected over the course of four months from three farms. By using 16S rRNA highthroughput sequencing techniques, bacterial communities were studied. Proteobacteria, Chloroflexi, Desulfobacterota, Firmicutes, Actinobacteriota, Bacteroidetes and Acidobacteriota were the dominant species at the phylum level in all samples. Spatial variation had a greater impact on the bacterial community composition and distribution of brackish pond sediments. Chloroflexi, Desulfobacterota, Spirochaetota and Latescibacterota were all substantially correlated positively with salinity. Moreover, salinity was negatively correlated with beta diversity. Salinity and total organic carbon were positively correlated with bacterial community distribution. This study was helpful to understand the response of bacterial communities to habitat changes, and provided a theoretical reference for the environmental supervision of aquaculture in sediment of brackish channel catfish ponds in Eastern China.