Abstract
Background
Environmental pollution from rare earth mining areas is of great concern, but the impact on microbial ecology and genomics has received little attention. In this study, the relationship between heavy metals and soil microbial community in the northern rare earth mining area was explored.
Methods
In order to study the detoxification mechanisms of heavy metals by microorganisms in this typical rare earth mining area, the study area was divided into three parts (mining area, residential area and control area). Analysis of microbial community diversity, structure and functional abundance using high-throughput sequencing techniques. Analysis of the effect of heavy metal pollution on the abundance of heavy metal resistance genes in soils of different regions using real-time fluorescence quantitative PCR.
Results
The results showed that the heavy metal pollution rules: mining area > residential area > control area. Under the condition of long-term heavy metal pollution, the original microbial community composition was changed, and the species richness and evenness of soil in mining areas were higher than that in residential areas. The high-throughput sequencing analysis showed that existed metal-resistant microbial communities such as Actinobacteria, Proteobacteria, Korarchaeota and so on under the stress of heavy metal. High concentrations of heavy metals can inhibit the activities of catalase and sucrase. According to Tax4Fun function prediction analysis, heavy metal accumulation increased the ABC transporter protein in microbial function. The results of fluorescence quantification experiments also demonstrated that the abundance of heavy metal resistance genes, czcA, czcB, czcC and czcD, encoding ABC transporter proteins, increased with increasing heavy metal concentrations.
Conclusions
In conclusion, the accumulation of heavy metals not only changed the soil physicochemical properties and the microbial community structure, but also decreased soil enzyme activities and increased the abundance of resistance genes, which activated the detoxification mechanism of heavy metals. which provided a reference for future ecological remediation.
Effects of Heavy Metal Pollution on Women in Coal Mining Areas
