Seasonal variations in microbial community structure in Yongding River

Microorganisms are important in river ecosystem, and the community structures change with time and space. Samples were collected from the gorge section and the urban section in Yongding River in August and November. Composition and seasonal succession of microbial community structures were studied by high-throughput sequencing, the dominant groups were found to be Cyanobacteria , Actinobacteria, Proteobacteria and Bacteroidetes. Microbial communities showed significant differences not only with change of time but also with change of space. Microbial diversity was found higher in August than in November, seasonal variation changed the community of upstream rather than downstream of the river. Human activities were found to have no impact on community diversity but decreased significantly community richness.