Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202505106
Open-pit coal mining causes severe soil nutrient depletion, limiting vegetation restoration. This study, conducted in the Baiyinhua No.2 mining area (Inner Mongolia), evaluated the effects of different fertilization strategies on soil nitrogen (N) and phosphorus (P) availability and microbial community responses. A field experiment was established in May 2023 with five treatments: low (L), medium (M), and high (H) phosphorus inorganic fertilizers, green manure (GM), and a microbial fertilizer (MF) containing nitrogen-fixing and rhizobia bacteria, compared to a control (CK). Results showed that MF significantly increased total carbon (TC) from 8.47 to 10.17 g·kg⁻¹ and total nitrogen (TN) from 0.37 to 0.56 g·kg⁻¹, while H significantly increased available phosphorus (AP) from 9.78 to 26.28 mg·kg⁻¹. Both treatments significantly altered fungal community structure, with increased relative abundances of Gibberella and Alternaria. The study concludes that MF and H improve soil nutrient availability by modulating fungal communities, with MF offering a sustainable biological approach for mine reclamation. These findings provide targeted fertilization strategies for restoring degraded mining soils and advancing green mining practices.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202503016
Open-pit coal mining severely damages soil and plant community structure and function, causing soil nutrient loss and ecological degradation. Vegetation reconstruction is a key measure for restoring degraded mining ecosystems, with the core challenge being the selection of suitable plant species and optimization of plant configurations. This study focused on the degraded ecosystem of the Baiyinhua open-pit mine in Inner Mongolia, screening native plant species for vegetation reconstruction experiments to investigate early-stage changes in soil nutrient availability and the underlying microbial mechanisms. Results showed that soil physicochemical properties and fungal community diversity exhibited strong adaptability during early reconstruction. However, soil fungal community composition and the relative abundance of saprotrophic fungi differed significantly among plant configurations. Leymus chinensis significantly increased the proportion of soil saprotrophic fungi from 67.28% in the control to 81.63%, while reducing the relative proportion of pathogenic fungi from 15.63% to 4.33%, demonstrating its potential to enhance soil health. Medicago rivularis improved soil microbial community composition and increased soil available phosphorus content, highlighting its capacity as an excellent pioneer species for optimizing soil nutrient availability. Furthermore, mixed sowing of grasses and legumes showed potential to enhance the nitrogen-fixing effect of legumes. Given the significant positive correlation between soil fungal community composition and total nitrogen and available nitrogen, the effects of different plant configurations on soil nutrient availability and biological health likely stem largely from the regulation of soil fungal community composition. In conclusion, achieving the goal of selecting optimal plant configurations still requires long-term continuous observation and analysis, particularly for optimizing configurations between high-quality grasses like Leymus chinensis and legumes.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202512014
Mining activities cause severe soil degradation and microbial diversity loss, impeding ecological restoration. This study evaluated the effects of a novel soil amendment, microporous bio-gravel (MBG), on bacterial and fungal community structure and function in degraded soil from the Baiyinhua open-pit mine, Inner Mongolia. A pot experiment with four MBG-to-soil volume ratios (CK, L=1:3, M=1:2, H=1:1) was conducted, with a simplified plant community and uniform fertilization. After 180 days, soil samples were analyzed via high-throughput sequencing and bioinformatics. Results showed that the medium ratio (M) significantly increased fungal Shannon index and evenness, while the high ratio (H) negatively affected bacterial communities. At phylum and genus levels, MBG promoted enrichment of Cyanobacteria and specific functional groups (e.g., nitrogen-fixing bacteria, Bacillus). Co-occurrence network analysis revealed peak complexity, modularity, and average degree in bacterial and fungal networks under the M treatment. Functional prediction indicated significant enrichment of pathways related to lipopolysaccharide biosynthesis, nitrotoluene degradation, and plant-pathogen interactions, alongside increased abundance of saprotrophic and ectomycorrhizal fungi. Mantel and VPA analyses showed that MBG indirectly regulated microbial community structure by improving soil physicochemical properties and plant traits, with stronger effects on fungi than bacteria. In conclusion, MBG optimizes the soil microhabitat and plant-soil-microbe interactions, modulating microbial diversity, network complexity, and functional potential. The medium ratio (1:2) was most effective, demonstrating potential for ecological restoration of degraded mine soils.