Hydrochemistry and microbial community characteristics and environmental response in different functional zones of a typical coal mine in Ordos
ZHANG Li
XU Zhimin
SUN Yajun
ZHU Lulu
CHEN Ge
GAO Yating
ZHAO Xianming
Abstract：To explore the distribution of microbial communities in different functional zones of coal mine and their response to hydrogeo-chemical characteristics,a coal mine in Ordos was taken as the research object.24 water samples were collected from six typical function-al zones involved in the whole process of the mine water source,formation,collection and discharge.Hydrochemical components detec-tion and high-throughput sequencing of microbial 16S rRNA genes were carried out.and multivariate statistical methods were used for se-quence data processing.The results showed that the hydrochemical type of mine water was high salinity SO4-Na type,which directly inher-ited the supplied water-source,while the concentration of characteristic pollutant SO42-was highest in coal roadways and surface water pools.The compositions of microbial communities in different functional zones presented significant differences.The dominant bacterial genera detected at the genus level included Thiothrix and sulfur oxidizing bacteria that could oxidize sulfides(i.e.,Thiothrix and Sulfuri-curvum),as well as new Sphingobacteria and Shortwave Monocmonas that can degrade organic matter(i.e.,Novosphingobium and Brevundimonas),while they distributed relatively high in coal tunnels and goafs.The abundances of aerobic Uliginosibacterium and Acinetobacter with strong adsorption and organic degradation,was highest in rock roadways.Bacteria related to nitrogen cycle(i.e.,Hy-drogenophaga and Rhodobacter)accounted for the higher proportion in water sumps and surface water.Microbial communities were sens-itive and closely related to the hydro-chemical processes.The distribution of microbial communities in underground coal mine was not only related to nutrients such as C,N,Ca and Mg,but also closely interrelated to redox sensitive substances such as Fe,COD and SO42-.Coal roadways and goafs are the key zones for groundwater pollution prevention and control.After mining disturbance,the low valent sulfides associated with coal have generated a large amount of SO42-through the chemical oxidation and catalytic oxidation of sulfur oxid-izing bacteria.However,it is worth noting that when the working pannel stopped for six months to three years,the characteristic pollutant SO42-was reduced by 15%-34%due to the physical or chemical adsorption,precipitation(dominated in the early stage),and the reduction of sulfate reducing bacteria(dominated in the later stage).This result indicated that the goaf had a certain degree of self-cleaning ability.In summary,the research results could provide theoretical supports for the engineering applications of mine water pollution prevention and control,which was reflected in the following two aspects:on the one hand,to reduce the generation of SO42-from the source by maintain-ing the anaerobic condition on the working pannel through nitrogen gas supply;on the other hand,after screening and cultivating the sulfate-reducing bacteria and organic matter degrading bacteria,they would be produced into bio materials,and added to the underground for in-situ remediation of groundwater pollution.
Keywords：coal miningmicrobial communityhydrodynamic characteristicbiogeochemical processesmine water
Publication Date：2023-12-25
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：17( 180-196 )