Niche analysis of microbial community reveals the South-to-North water diversion impacts in Miyun Reservoir

Abstract

The South-to-North water diversion impacts on microbial community niche were investigated in the water receiving area. In this paper, the community structure, niche breadth and overlap of the dominant genus were determined to approach the distribution features of microbes and the community changes in Miyun Reservoir. Our results showed that before water transfer, the main bacteria phylum was Proteobacteria, Bacteroidetes, Cyanobacteria, Firmicutes and Actinobacteria. The niche breadth range (OMI value) of dominate bacteria genus was 0.01~0.54, and the tolerance value range was 0.55~4.56. After water transfer, Proteobacteria, Cyanobacteria, Actinobacteria, Bacteroidetes and Verrucomicrobia were the dominate phylum. The niche breadth range of dominate bacteria genus was 0.00~0.38, and the tolerance value range was 0.55~4.56. It indicated that after water diversion, the relative abundance of the Proteobacteria and Verrucomicrobia increased significantly (p<0.05), and the ecological niche of the genus Candidatus Methylacidiphilum, Chitinophagaceae and OM27 clade was significantly differentiated (p<0.05). The niche overlap results suggested that the inter-species niche competition becomes more intense after the water transfer, which reflected the different utilization ability of each bacteria genus in the new aquatic environment of the Miyun Reservoir.