Soil properties under different ecological restoration modes for the quarry in Yanshan mountains of Hebei province, China

The ecological environment of quarry mining area is fragile, and the vegetation restoration cycle is long and difficult, so scientific and appropriate artificial vegetation is of great significance to ecological restoration. The purpose of this study was to evaluate the herbaceous and woody vegetation restoration, including Medicago sativa (Me), artificial miscellaneous grass (Mg), Rhus typhina (Rh), fruit orchard (Or) and Pinus tabulaeformis (Pi), to investigate the soil physicochemical properties and the structure of the microbial communities, and to reveal the correlation between them. The results addressed that Medicago sativa and artificial miscellaneous grass had significant effect on soil remediation, which were conducive to scientific and efficient ecological restoration, and could promote ecological restoration in the damaged ecosystems. While, the modes of Rh and Pi were not suitable for ecological restoration in this study area because they had strong allelopathy. Another arborous restoration mode of Or showed a better improvement effect (including soil nutrients, soil microbial diversity, etc.) than that of Rh and Pi. The findings also indicated that the herbaceous vegetation restoration modes of Me and Mg significantly increased the relative abundance of Proteobacteria, Acidobacteria, Actinobacteria bacteria, Ascomycota and Mortierllomycota fungi, and reduced the relative abundance of Firmicutes bacteria and Basidiomycota fungi. This study also revealed that the trend of bacterial localization in the fruit orchard, artificial miscellaneous grass and Medicago sativa was more obvious. Among many soil abiotic factors, the contents of organic matter, available nitrogen and pH were the most important factors affecting soil microbial community.

Automated summary

The ecological environment of quarry mining areas is delicate, making vegetation restoration challenging. This study evaluated the restoration of different herbaceous and woody vegetation types and their impact on soil remediation and microbial communities. The results showed that Medicago sativa and artificial miscellaneous grass were effective in soil remediation and promotion of ecological restoration. However, Rhus typhina and Pinus tabulaeformis were not suitable due to their strong allelopathic effects. Fruit orchard restoration showed better improvement compared to Rhus typhina and Pinus tabulaeformis. Furthermore, the study revealed the importance of organic matter, available nitrogen, and pH in determining soil microbial community composition.