Aquatic Microbial Community Characteristics and Influencing Factors in Urban Landscape Rivers

Urban rivers play an important role in ecological landscapes, but the influencing factors of microbial community structure and diversity have not been further studied. This study took three urban landscape river water bodies in Wuhu, Anhui Province, as examples. Determination of the physical and chemical properties of the water samples collected was performed. The Illumina platform was used for double-terminal sequencing of community DNA fragments. The specific composition of samples at different taxonomic levels was obtained to determine the microbial community structure. The influence of environmental differences on river water quality, bacterial community structure and diversity of urban rivers was discussed. The results showed that (1) a maximum of 35 phyla were detected in urban landscape water bodies, among which Proteobacteria were the most dominant phyla, accounting for 63.62% on average. Then, Actinobacteria and Bacteroidetes were observed. The content of cyanobacteria in the streams near the residential area is higher than that in the other two streams. (2) Due to the different functional areas nearby, there were spatial differences among microorganisms in urban river water. The abundance and diversity of bacteria in streams near residential areas decreased significantly. The abundance and diversity of bacteria in river water samples with a more complex surrounding environment were the highest. (3) DO, pH, NH4+-N, NO3--N and EC were key factors affecting bacterial communities. Proteobacteria was positively correlated with DO. Actinobacteria were positively correlated with NO3--N. At the genus classification level, Azospirillum was highly correlated with DO and EC.