The influence of transplanted trees on soil microbial diversity in coal mine subsidence areas in the Loess Plateau of China

Abstract

Soil microbial diversity in coal mine subsidence areas is closely associated with vegetation restoration. In this study, we compared the diversity of soil bacteria and fungi under different vegetation restoration modes in the mine subsidence area of the Daliuta coalmine region in western China. The abundance of dominant bacteria, including Actinobacteria, Proteobacteria, Chloroflexi, and Acidobacteria, was 29.43–34.68%, 15.87–24.75%, 13.09–19%, and 12.06–15.36%, respectively. The abundance of dominant fungi, Ascomycetes and Zygomycetes was 23.96–71.08% and 10.42–56.26%, respectively. The diversity indices (Sobs, Shannon, and Chao1) of the rhizosphere soil bacteria and fungi were significantly lower in the primary Stipa breviflora phytocommunity than in the phytocommunities of transplanted trees. Among physicochemical soil parameters, total nitrogen (TN), total phosphorus (TP), water content (WC), and pH affected soil bacterial diversity, and available phosphorus (AP) and TN affected bacterial community structure the most. Furthermore, WC affected soil fungal diversity, whereas TP and TN mostly affected the fungal community structure. However, edaphic factors did not uniformly affect all microbial groups. Although TN, WC, and AP significantly influenced Actinobacteria and Proteobacteria, TP was distinctly negatively correlated with the abundance of Ascomycota, Basidiomycota, and Zygomycota. However, TN evidently influenced the abundance of Zygomycota. The rhizosphere microbial diversity of the S. breviflora community (CK phytocommunity) differed from that of the transplanted tree communities in the study area. The transplanted trees promoted soil microbial diversity, and different edaphic factors had different influences on the community composition of rhizosphere bacteria and fungi. The outcome may benefit the construction of green mines in the study area.