Variations of Soil Chemical Properties and Microbial Community around the Acid Reservoir in the Mining Area

Abstract

Acid Mine Drainage (AMD) is unique acidic wastewater produced in the process of iron mining and utilization. The soil and wetland contaminated by AMD in a mining area in Ma’anshan were studied in this paper. The physical and chemical characteristics and microbial community structure of the samples were analyzed to evaluate the resident soil pollution. The results showed that the soil around the acid reservoir was seriously polluted by metals such as Fe, Mn, Cd, and sulfate, and the loss of organic matter and total nitrogen was serious. With the increased distance between soil samples and the acid reservoir, the pollution degree of AMD decreased, the soil pH, organic matter and total nitrogen contents increased gradually, the soil microbial species increased slightly, and the diversity index increased. Bacillus, Lactococcus, and other bacteria with hydrolytic acid-producing functions accounted for more than 55.0% of the total bacterial community. Desulfuromonas, Desulfobulbus, and other genes involved in sulfur metabolism accounted for more than 24.0% of the total microbial community. In addition, Nitrosophaera, Nitrosopumilus, Methanoregula, and Methanosphaerula, which were involved in nitrogen cycling, were the dominant bacteria in the sampled soil. Our findings provide the basic data to support the mineral industry in China as well as for ecological functional evaluation based on species differences.