In situ restoration of soil ecological function in a coal gangue reclamation area after 10 years of elm/poplar phytoremediation

• Published in: Journal of environmental management 2022-03, Vol.305, p.114400-114400, Article 114400
• Main Authors: Bai, Dong-sheng, Yang, Xu, Lai, Jin-long, Wang, Yi-wang, Zhang, Yu, Luo, Xue-gang
• Format: Article
• Language: English
• Subjects: Biodegradation, Environmental; China; Coal - analysis; Coal gangue; Coal Mining; Functional pathway; Ion group; Microbial diversity; Soil; Soil Microbiology; Soil Pollutants - analysis
• ISSN: 0301-4797; 1095-8630
• DOI: 10.1016/j.jenvman.2021.114400

The soil ecological health risks and toxic effects of coal gangue accumulation were examined after 10 years of elm/poplar phytoremediation. The changes in soil enzyme activities, ionome metabolism, and microbial community structure were analyzed at shallow (5–15 cm), intermediate (25–35 cm), and deep (45–55 cm) soil depths. Soil acid phosphatase activity in the restoration area increased significantly by 4.36–7.18 fold (p  middle > deep. The soil community structure, determined by 16S diversity results, was changed significantly in the restoration area, and the abundance of microorganisms increased at shallow soil depths. Altererythrobacter and Sphingomonas species were at the center of the microbial weight network in the restoration area. Redundancy analysis (RDA) showed that S and Na are important driving forces for the microbial community distributions at shallow soil depths. The KEGG function prediction indicated enhancement of the microbial function of the middle depth soil layers in the restoration area. Overall, phytoremediation enhanced the biotransformation of soil phosphorus in the coal gangue restoration area, reduced the soil content of several harmful metal elements, significantly changed the structure and function of the microbial community, and improved the overall soil ecological environment. [Display omitted] •The content of heavy metals and sulfur in the soil of the restoration area has decreased.•The microbial abundance of shallow soil in the restoration area increased the most.•Altererythrobacter and Sphingomonas occupy an important position in the soil restoration area.•The ecological function of the middle depth soils in restoration areas has been strengthened overall.