Analysis On System Function And Sediment Characteristics Of The Ecological Water System In The Residential Community Of Wuhan

Based on the rain water control system and the ecological water system arrangement of the residence community in Wuhan, the purifying effect of the cell engineering measures was researched in this paper. By the analysis of physical and chemical property and the high-throughput analysis of the bottom sediment in the ecological water system, the microbial community structure and diversity were studied, to analyse the effects of the physical and chemical property on the microbial community structure.This ecological residential community included the rainwater harvesting system, the rainwater transfer system and the rainwater purification storage system. The rainwater was collected by the green roof, the permeable pavement and the lawn, which have the retention and the infiltrate function, and then the rainwater was transferred into the landscape lake by the ecological swales. The pollutant in the rainwater can be removed by the ecological swale and the landscape lake, and the landscape lake has the function of regulating and stabilizing the water quality. According to the analysis results of the water quality index, p H, TP, NO3-N, CODMn and NO2-N, it was found that it satisfied the recrea-tional water quality C standard.By the analysis of physical and chemical property, it was found that the salinity was the lowest and the content of rapidly-available phosphorus was the highest in the surface soil. The content of humus was the highest in the bottom sediment of the landscape lake, which shows black brown. The electric conductivity had a significant correlation with LOM, so the salt content played an important role in the process of decomposing and using the organic matter. The content of rapidly-available phosphorus had a significant correlation with the electric conductivity, so the salt content related to the absorbing of plants to the rapidly-available phosphorus. By the principal component analysis the physical and chemical property, it was found that the difference of physical and chemical properties in the sediment and soil was very big.Based on the analysis of ACE and Chao, the abundance of the microbial community in the sediment was higher than the surface soil, and the quantity of microbial was rich. According to the distribution of Simpson and Shannon, the microbial diversity in the pand of the ecological swales and the landscape lake was higher.By the high-throughput analysis of the microbial community structure in the sedi –ment, the relative abundance of proteobacteria was the highest. The relative abundance of cyanobacteria in the ecological swale II and the middle of the ecological swale I was high-er than the others, because it had light. According to the heatmap and the cluster analysis tree of the phylum, the microbial community structure responsed to the environment factors obviously. The sediment of the landscape lake and the ecological swale was anaerobic environment, so the relative abundance of anaerolineae was higher than the surface soil, which was up to 22.7%. The physical and chemical property of the sediment had a great effect on the alphaproteobacteria.The content of the humus in the sediment had the grestest effect on the microbial community structure. The humus had a significant correlation with ACE, Chao, Simpson, Shannon and Coverage, the correlation coefficient are 0.707?0.750?0.742?0.520?0.654 and 0.796. The microbial community structure on the phyum, class and genus was influenced by the physical and chemical properties, and humus, salinity and the rapidly-available phosphorus had the greatest effect.