Insight into the Characteristics of Soil Microbial Diversity during the Ecological Restoration of Mines: A Case Study in Dabaoshan Mining Area, China

Li Fan,Zhenggang Xu,Yunlin Zhao,Wendan Feng,Ping Mo,Guiyan Yang,Weiping Zhao

doi:10.3390/su132111684

Abstract

Soil microorganisms play an important role in regulating a variety of ecological functions. In recent years, the research on ecological restoration after mining has made people more aware of the importance of microbial diversity to ecosystem restoration. The present study investigated the effect of ecological restoration on microbial community structure and its relationship with soil physicochemical properties in the Dabaoshan mining area, China. High throughput sequencing technology was used to analyze and compare the microbial community composition of three types of soil (undamaged area, unrestoration area, and ecological restoration area). The contents of organic carbon, total nitrogen, and total phosphorus were 2.38–12.97 g/kg, 0.39–1.62 g/kg, and 0.99–1.51 g/kg, respectively. In different soil states, undamaged area and ecological restoration area were significantly higher than those in unrestoration area. The results showed that the structure of soil microbial community was significantly correlated with soil physicochemical properties, and formations in the repaired and unrepaired soils were different. Operational Taxonomic Unit (OTU) cluster analysis and diversity index analysis showed that soil microbial community changed at phylum and genus levels. The results showed that at the phylum level, all soil samples contained Firmicutes, Proteobacteria, and actinobacteria. Firmicutes and Proteobacteria of the ecological restoration area (ER1, ER2) were the highest in relative abundance compared with other samples, accounting for more than 45%. Proteobacteria and Acidobacteria were the dominant phylum in the undamaged area (UD), accounting for 32.7% and 22.3%, respectively. It can be seen that soil restoration produced a new dominant population, and Proteobacteria showed an absolute competitive advantage in the mining soil.

Highlights

The findings of this study suggest that vegetation restoration in the mining area of Dabaoshan can significantly improve Operational Taxonomic Unit (OTU), bacterial community richness, and diversity indices and soil physicochemical properties
The contents of organic carbon, total nitrogen, and total phosphorus in different soil states were positively correlated with microbial diversity, and the contents of carbon, nitrogen, and phosphorus in soil affected the microbial diversity and community structure
Canonical Correlation Analysis (CCA) results showed that there was a strong correlation between bacterial community structure and physicochemical properties in ecological restoration areas (ER1 and ER2)

Summary

Introduction

Mineral resources bring great economic benefits to human beings, and cause serious pollution to the environment of mining areas and damage to the ecosystem. The vegetation, soil, and landforms in the mining area are damaged [1]. Due to the unconscionable exploitation and utilization of mineral resources, soil pollution is becoming more and more serious [2]. Soil pollution in mining areas migrates under surface runoff and biogeochemistry, endangering the environmental quality of adjacent areas and endangering human health by contaminating food and drinking water [3,4,5]. The topsoil needs to be stripped during mining, resulting in serious

Methods

Results

Discussion

Conclusion