Effects of Xiantao sewage treatment on microbial community structure of shallow groundwater in wetland

In order to solve the problem of urban domestic sewage treated by semi natural wetland method with high connectivity between surface water and underground water in the flood diversion channel, Whether there is a blank study on the pollution of shallow groundwater. The community structure and abundances of CODCr, total nitrogen, total phosphorus and microorganism were added to the surface water. Environmental factors such as CODCr, TN, TP, NH4+-N and microbial community and abundance indices were monitored through surface water and groundwater. In this study, physical and chemical indicators, microbial diversity and community structure of 12 water samples from Xiantao artificial wetland were studied by using the Illumina Miseq sequencing technique and the resulting microbial data were statistically analyzed in combination with environmental variables. The results showed that CODCr concentration had a very significant positive correlation with total microbial communities (r=0.530, P<0.01), NH4+-N and TN were significantly positively correlated (r=0.337 and 0.325, P<0.05). In addition, CODCr concentration was highly positively correlated with abundant groups (r=0.520, P<0.05), NH4+-N and TN were significantly positively correlated (r=0.325 and 0.304, P<0.05). For rare taxa, they might be more sensitive to the environment than their abundant groups. The relative abundance of the rare group is 0 at the depth of 10m, so we should carefully evaluate microbial reaction (rare group) environmental conditions in the future.