Dynamic Research On Microbial Community Of Xiaolangdi Reservoir

With the industrialization and urbanization of our country,promote the development of our economy.At the same time,produced severity contaminated to urban river reach and groundwater,which causing the drinking water issue more critical.To relieve the pressure on water supply,the reservoir bears the burden of relieving water supply pressure.The Xiaolangdi reservoir multipurpose project has a comprehensive function of regulating water and sediment,water supply,electricity generating and flood control,the water quality safety of Xiaolangdi reservoir is closely linked with the drinking water.In order to monitor the water quality more efficiently,protect ecological diversity of xiaolangdi reservoir and safeguard the human water security.Three sampling sites in the xiaolangdi reservoir area were selected,investigate the water quality and phytoplankton in the water.Studied the dynamic change of water quality,the relationship between chemical parameters and the number of culturable bacteria of the xiaolangdi reservoir.To studied the diversity of phytoplankton in water by means of microscope observation and high-throughput sequencing.The research results are as following:Water quality overall condition is good during 1-year monitoring period,water quality of three monitoring sites basically belongs to level ? without regard to TN and TP.The results from eutrophication evaluation indicated that the nutrition levels of water is mesotrophic in the majority,the proportion of light eutrophication was14%.Through the count of culturable bacteria of the total 36 samples can be found that there were differences in total bacteria between different monitoring points in the same month or the at the same monitoring stations in different months,and the correlation between different monitoring points of cultivable bacteria and water physicochemical parameters is not the same.The results of Algae counting under microscope showed that dominant population of three sampling points is same,which are mainly Synedra acus,Melosira,Fragilaria and microcystis.However,dominant population of sampling site C showed its unique characteristics,is different from two other sampling sites.Illumina Hiseq sequencing results showed that the species abundance detected in36 samples of the top 10 phylum are Arthropoda,Mollusca,unidentified-Eukaryota,Diatomea,Basidiomycota,Streptophyta,Chlorophyta,Rotifera,Ascomycota and Chytridiomycota.In the three sampling points,monitoring point R has higher species richness and more unique species compared to the other two monitoring points,but its diversity fluctuates greatly.The content of dominant population is higher,community evenness is poor,but the community diversity is relatively stable in monitoring point K.The species richness is the lowest and fluctuation range of diversity is larger in monitoring point C.Analysis of Beta diversity index and Species abundance clustering showed that the similarity of the dominant between sampling point R and K is higher than sampling point C,diversity between the sampling point R and C was most.The Spearman correlation analysis and Canonical Correspondence Analysis of the samples showed that the biggest impact for trend of community types and species distribution is temperature,the distribution of the species has an obvious correlation with dissolved oxygen and p H.