Experimental Study on the Microbial Community Structure of the Sediment of Pi River under the Different pH in Winter

In order to solve the poor self-purification ability of low temperature water in winter, the microbial community structure in the sediment of Pi River water (located in West Anhui) was investigated experimentally in this study. Firstly, the sediment was sampled in the lower reaches of Pi River and prepared with the different pH (5.0, 5.5, 7.0 and 8.5); secondly, the prepared samples were tested by the high-throughput sequencing technology and the tested results showed that more than 40% of the bacteria in the sediment samples had an average relative abundance of less than 1.5% and the bacterial community was relatively dispersed and diversified; the relative abundance of Acidobacteria was the lowest, while Proteobacteria and Bacteroidetes were the opposite; additionally, the abundances of Nitrosomonadaceae, Nitrospirae and Nitrosomonadales samples (pH = 5.5, 7.0 and 8.5) were all less than 5%, while the abundance in pH = 5.0 samples was less than 1%; the specific species of alkaline sample is 0, because acidity had a great influence on the structure of microbial community, especially nitrifying bacteria, furthermore, the optimal environment for bacterial growth in sediments had an acidity threshold. Accordingly, this paper will provide a reference for the poor self-purification of water at low temperature in winter.