Dynamics of bacterial communities in a river water treatment wetland

Bacteria play important roles in the removal of inorganic and organic pollutants in constructed wetlands (CWs) used for surface water treatment, however, the environmental variables driving the change of bacterial community remain poorly understood. The present work explored seasonal and spatial dynamics of bacterial communities in a large CW used for river water treatment and the associated environmental variables. Quantitative PCR assay and high-throughput sequencing analysis were used to determine the abundance, richness, diversity, and structure of wetland bacterial community. Bacterial abundance was correlated to nitrite and temperature, while bacterial diversity could be influenced by pH as well as carbon, nitrogen, and phosphorus. Bacterial community structure might be shaped by nitrogen and phosphorus. A considerable difference in bacterial community composition existed between wetland soils and sediments. Proteobacteria (accounting for 33–60%) was the largest bacterial phylum, and Chloroflexi (5–24%) was also abundant. The abundance, richness, diversity, and composition of the bacterial community were influenced by wetland plant type and wetland trophic status.