[Response and Assembly Process of Soil Microbial Communities Under Different Reclamation Measures]

Reclamation is essential for restoring the ecological function of soil in mining areas. However, the microbiological mechanism of soil ecological function reconstruction under different reclamation measures still needs to be clarified. Clarifying the characteristics of soil bacterial and fungal communities, assembly mechanisms, and their relationship with physicochemical properties under different reclamation measures is crucial for reshaping the ecological stability of soil in mining areas. Metagenomic sequencing technology was combined with the null model and neutral model to analyze the differences in soil microbial diversity, community composition, network structure, and community assembly process between the reclaimed natural recovery area （LH） and the reclamation fertilization area （MM）. The results suggested that： ① Compared with that in the LH treatment, the MM treatment significantly increased the soil nutrient content, and the total nitrogen （TN）, total phosphorus （TP）, available phosphorus （AP）, and available potassium （AK） contents increased by 34.70%, 72.72%, 468.98%, and 45.74%, respectively （P<0.05）. ② The dominant bacterial and fungal communities did not change under the LH and MM treatments； however, the abundance of bacterial communities changed significantly. Compared with that in the LH treatment, the relative abundance of Acidobacteria increased significantly by 5.4% in the MM treatment, while the relative abundance of Candidatus Rokubacteria decreased significantly by 235.72% （P<0.05）. Under different reclamation measures, the indicator microorganisms of bacterial and fungal communities changed. ③ Compared with that in the LH treatment, the MM treatment increased the complexity of bacterial networks, decreased the complexity of fungal networks, and increased the number of soil bacterial nodes and links. The reclamation measures transformed the key bacterial groups from Proteobacteria to Candidatus Rokubacteria and Planctomycetes. The key group of fungi was Ascomycota. 4.） The deterministic process dominated the assembly of bacterial and fungal communities. Homogeneous selection contributed the most to the bacterial community assembly in the LH treatment, and heterogeneous selection contributed the most to the MM treatment. The fungal communities were all dominated by heterogeneous selection. These results provide new insights into the soil microbial community structure and ecological function restoration in coal mining subsidence reclamation areas.