Influence of high-sulfur coal cover on composition and diversity of soil bacterial community in mining areas

Abstract:

[Background] The study of soil microbial ecology is very important for ecological investigation of pollution in mining areas and ecological restoration of mining areas. The influence of high-sulfur coal cover on underlying soil microbial community is still unclear. [Objective] The purpose of this study is to explore the influence of long-term high-sulfur coal cover on bacterial community composition and diversity of the underlying soil in coal mining areas. [Methods] Three types of soil samples (high-sulfur coal cover layer, soil beneath high-sulfur coal cover layer, soil as control) were collected from coal yard of a high-sulfur coal mine. The influence of high-sulfur coal cover on soil properties and soil bacterial community was studied by measuring soil physical and chemical properties and using high-throughput sequencing technology. [Results] Compared with the soil as control, in the soil beneath high-sulfur coal cover layer, the pH value decreased, but the contents of sulfate, organic matter, hydrolyzed nitrogen and available phosphorus increased. For the underlying soil bacterial community, the diversity index decreased and the composition changed obviously. At genus level, the relative abundance of Bacillus in the underlying soil was higher than that of the control. The regularities of relative abundances of Acidiphilium and Sulfobacillus in three sample groups were “high-sulfur coal cover layer>its underlying soil>soil as control”. The preponderance of sulfur-oxidizing bacteria in the condition of high-sulfur coal and its influence on the underlying soil could be confirmed. The co-occurrence network analysis showed that Acidiphilium and Sulfobacillus played an important role in the soil bacterial community of the area covered by high-sulfur coal, and had a great impact on other bacterial genera. [Conclusion] The high-sulfur coal cover and the predominance of sulfur-oxidizing bacteria in it have obvious influence on the physical and chemical properties and the bacterial community of the underlying soil. The research results are helpful to enhance the understanding of soil microbial ecology in mining areas, and provide theoretical basis for the ecological restoration of high-sulfur coal mining areas in microbiology.