Study On The Influence Of Coal Mine Goaf Water On The Water Ecological Environment Of Yangquan Shandi Basin And Its Prevention And Control Countermeasures

In order to explore the effects of coal mine goaf water on the water ecological environment of Shandi river water,the collection of exudate surface coal mine goaf water,Shandi river water and sediments were conducted in Yangquan City during the water-stable period,wet period and dry season of 2020.During this period,the collected samples were examined for chemical factor content using atomic absorption spectrometry(AAS),Barium Chromate Spectrophotometry,and flame AAS;The compositional features of bacterial communities of samples were analyzed by high-throughput sequencing of 16 S r RNA genes,and plots of sample dilutions,histograms of species distribution at the genus level,PCo A plots of species compositional differences between samples and environmental factor related CCA plots were generated,the species and amount of plankton in water samples were observed and recorded using a biomicroscope,and the obtained results were subjected to Shannon Wiener diversity index,Mar Galef richness index,Pielou evenness index and Jaccard community similarity coefficient Q were calculated.The effects of goaf water on the physicochemical characteristics,phytoplankton and bacterial community composition of the bottom river and sediments were investigated by comparative analysis(1)When the goaf water was put into the Shandi River,it would significantly decrease the p H of the river water and sediment,and increase the iron content significantly.Besides that,the river water showed a significant upward trend in total hardness,Mn,Cu,Zn and Cd contents.(2)A total of 14 species of planktonic algae affiliated with the phyla cyanobacteria,diatoms,naked algae and chlorophytes,were detected in the Shandi river.The presence of benthic and zooplankton was not found in the river.Only two phyla,Brachybacterium and naked alga,appeared in river water at the water exudate point of coal mine goaf in Xiaogou coal mine,while in the uncontaminated Shandi River,the genera fibrillaria,navicular alga and cocoon type alga occupied the main body preponderance.According to the evaluation of phytoplankton diversity index,it can be concluded that the species diversity of phytoplankton in Shandi River is generally small,and the river water is heavily polluted.After the inflow of goaf water,the pollution degree of river water will be significantly increased,which not only leads to a significant decrease in the species diversity of phytoplankton,but also greatly changes the composition structure of the original phytoplankton community.(3)The goaf water would significantly reduce the diversity and abundance of microbial communities in the Shandi river,which led to the emergence of large amounts of the genera Ferrovum,Acidiphilium,Acidithiobacillus,and Leptospirillum,and a significant correlation between these bacteria and the content of p H、Mg and Ca.The acid fast protozoan Euglena＿Mutabilis also appears in the water and the undefined Epipyxis＿sp.＿PR26KG。However,in the uncontaminated river water,mainly pathogenic bacteria such as Acinetobacter and Psychrobacter were detected,and a small amount of Sphingobacterium Novosphingobium and Prevotella＿9 were detected in the water-stable period and dry season,respectively。(4)The diversity and abundance of the bacterial community were significantly reduced in the sediment contaminated with goaf water.The high number of acidophilic iron-sulfur metabolic bacteria also appeared in the sediment,but the species were not exactly the same as those in the water samples.In addition to Acidiphilium,Leptospirillum,Ferrovum,Ferrimicrobium and Ferrithrix,the protozoan Euglena＿mutabilis although also emerging,does not have the advantage that the protozoan Euglena＿mutabilis and the top four genera were more affected by the content of metallic iron.In short,after the goaf water was pooled into the Shandi river,it greatly changed the ecological environment of the original river.This study from the perspective of environmental ecology and prompt people to prevent and control the harm of goaf water is urgent,suggesting that the extant coal industry in Yangquan city should strengthen the investigation and monitoring efforts on the effects of water environment during the later stage of mining and make a good job in pit closure,The process of "" neutralization constructed wetland + bacteria linkage "" was applied to treat the goaf water.