Characteristics Of Microbial Community In Coal Mining Subsidence Area Of Huainan

Coal mining in eastern China leads to the formation of a large area of subsidence area,and the dense regional river network and high diving level contribute to the formation of the subsidence area of coal mining.By 2021,the total area of subsidence area of coal mining in Anhui Lianghuai Region is 580km²,with water resources amount to 240 million m³,which is an important component of regional water resources.The water ecological environment quality is the guarantee of efficient development and utilization of water resources,and the structure and distribution characteristics of microbial community are important indicators of water ecological environment,which are closely related to water environmental quality.In recent years,many scholars have carried out investigation and evaluation of water resources environment in coal mining subsidence area,but the spatial and temporal evolution characteristics of microbial community structure in water environment of subsidence area have not been systematically studied.Papers in huainan mining area as the study area,pan choose typical enclosed subsidence waters（GQ,XJJ,PJ）and an open subsidence waters（mud）river as the research object,investigation of winter and summer,water environment and the microbial community diversity index of water environment and space-time distribution of the microbial community characteristics,analysis the influence factors of microbial community structure change of time and space,Reveal the key driving factors of microbial community evolution in sunken waters.The main conclusions are as follows:（1）Spatial and temporal distribution characteristics of water quality in coal mining subsidence area:all water quality indexes changed with season in time,except p H,EC and BOD₅,the trend of winter was less than summer.There was no significant difference in spatial water quality indexes in winter,and the trend of closed subsidence area<open subsidence area,and GQ>XJJ>PJ in summer.（2）Water environmental quality evaluation results:single factor evaluation,nemerow comprehensive pollution index evaluation,optimization weight comprehensive water quality identification index evaluation,the conclusion is that the water quality of mining subsidence area is in"Ⅲ-Ⅳ"class"Surface Water Environmental Quality Standard"（GB3838-2002）,but TN,TP and NH₃-N indexes in the lower nihe river are"Ⅴ"class level.Evaluation of comprehensive nutritional status index:the water quality of all subsidence waters in the study area was good in winter,and there was no eutrophication.In summer,guqiao and Panji were slightly polluted,while Xiejiaji was moderately polluted.HTQJ in the upper reaches of nihe River,LYC in the middle reaches and XLJ in the lower reaches are slightly polluted,while SMC in the middle reaches and DZ in the lower reaches are moderately polluted.（3）The spatial and temporal distribution characteristics of microbial communities in coal mining subsidence waters can be seen from the Chao1 index,Shannon index and Simpson index of six groups have the same change trend.In general,the abundance and diversity of bacteria in panxie mining area are lower in winter than in summer.In different seasons,there are certain differences in the bacterial community structure of the subsidence waters,which are as follows:The dominant bacteria in winter mining subsidence area are Proteobacteria,Bacteroidetes,Actinobacteria and Cyanobacteria,and their relative abundances are as follows:56.62%,3.91%,5.90%,1.87%;In summer,the microbial community is more diverse at the phylum level,The main dominant bacteria include Proteobacteria,Bacteroidetes,Actinobacteria,Cyanobacteria,Verrucomicrobia,and Plan The relative abundance of Ctomycetes,Firmicutes and Chloroflexi were 51.74%,17.82%,13.54%,5.17%,4.21%,2.59%,1.42%and 1.39%,respectively.Similar patterns were observed at the class and genus levels.（4）The correlation analysis of bacterial colony and environmental factors in mining subsidence area shows that EC,TN,TP and p H were the key environmental factors affecting the flora in mining subsidence area,and the correlation between dominant colonies and various forms of nitrogen was very significant.RDA analysis results showed that EC,TN,TP and COD were the main environmental factors that caused the changes of bacterial community structure in coal mining subsidence waters at various classification levels in two seasons.Chla had a more obvious effect on the bacterial community structure in summer,and nitrogen was the most critical among all environmental factors.The variation trend of sulfur metabolism genes:The abundance of sulfur metabolism genes in closed subsidence area decreased firstly and then increased with time,while in open subsidence area there was no obvious change.Figure 19 table 22 reference 123...