Abstract:
Coal mining often causes large areas of subsidence land collapse in mining areas, leading to a significant increase in the vulnerability of the local ecosystem. Reclamation with coal gangue filling is commonly adopted to repair the subsidence of mining areas, and soil bacterial community plays an important indicative role in reflecting the quality and ecological health of reclaimed soil. In order to understand the impact of reclamation of subsidence area with coal gangue filling on soil bacterial community, takeing surrounding normal cultivated land (CK) as controla comparison, field sampling and high throughput Illumina Miseq 16S rRNA gene sequencing were used to analyze the soil physical and chemical properties, the variations of soil bacterial community composition and diversity, and the relationship between them in different soil depths (0-20, 20-40 and 40-60 cm) of reclaimed land filled with coal gangue (G). The results showed that:① Ccoal gangue reclamation significantly changed the soil physical and chemical properties in the study area, the changing trend of soil properties under different soil depths was obviously different.② The diversity and abundance of soil bacterial community in the reclaimed land filled with coal gangue were lower than those in normal cultivated lands, which also showed a significant negative correlation with soil depth (P<0.05). The composition difference of bacterial community in the 40-60 cm soil layer due to coal gangue filling was greater than that in other soil layers. Besides, Proteobacteria, Actinobacteria, and Acidobacteria were the dominant phyla in all treatments.③ Results from canonical correlation analysis (CCA) and Pearson correlation analysis indicated that pH, Moisture Content (MoiC), Soil Organic Carbon (SOC), Available Phosphorus (AP), and Available Potassium (AK) were the main soil physical and chemical properties in shaping soil bacterial communities, and the dominant bacteria phyla were only significantly associated with some soil properties such as pH, AP and MoiC.