Effects of coal-derived compound fertilizers on soil bacterial community structure in coal mining subsidence areas

Abstract

The land damaged by coal mining can be recovered to healthy condition through various reclamation methods. Fertilization is one of the effective methods to improve soil fertility and microbial activity. However, the effects of coal-derived compound fertilizers (SH) on bacterial communities in coal mining subsidence areas still remain unclear. Here, we studied the effects on the nutrient characteristics and bacterial communities in fertilizer-reclaimed soil (CK, without fertilizer; CF, common compound fertilizers; SH, coal-derived compound fertilizers) in coal mining subsidence areas and we applied SH with four different nitrogen application rates (90, 135, 180, and 225 kg/hm2). The results showed that the application of SH significantly increased the contents of available nitrogen (AN), available phosphorus (AP), available potassium (AK), total phosphorus (TP) and soil organic matter (SOM) compared with CK, as well as the bacterial richness (Chao1) and diversity (Shannon) in reclaimed soil that increased first and then decreased with the increase of nitrogen application. Under the same nitrogen application rate (135 kg/hm2), the nutrient content, Chao1 and Shannon of SH2 treatments were higher than those of CF treatment. Meanwhile, SH increased the relative abundance of Proteobacteria, Actinobacteria and Gemmatimonadetes. LEfSe analysis indicated that the taxa of Acidobacteria and Actinobacteria were significantly improved under SH treatments. Canonical correspondence analysis (CCA) and Variance partitioning analysis (VPA) showed that SOM was the most important factor affecting the change of bacterial community structure in reclaimed soil. In conclusion, application of SH can not only increase nutrient content and bacterial diversity of reclaimed soil, but also improve bacterial community structure by increasing bacterial abundance.

Seasonal changes of soil microbiota and its association with environmental factors in coal mining subsidence area

“…The top ten clades in summer abundance were Proteobacteria , Acidobacteriota , Firmicutes , Bacteroidota , Gemmatimonadota , Actinobacteriota , Verrucomicrobiota , Desulfobacterota , Chloroflexi and Myxococcota , while the top ten clades in winter abundance were Proteobacteria , Acidobacteriota , Gemmatimonadota , Bacteroidota , Firmicutes , Acidobacteriota , Myxococcota , and Verrucomicrobiota , Chloroflexi and Desulfobacterota . This result is similar to other studies of soil microbes in coal mining subsidence areas (Meng et al 2023 ; Fang et al 2023 ). In addition, in our study, although alpha diversity analysis showed no significant difference in soil microbes between the two seasons, the summer soil microbial community annotated more OTUs and the number of OTUs specific to the two seasons far exceeded the number of shared OTUs (Supplementary Fig.…”

“…On the other hand, microbial diversity is directly affected by the content and presence patterns of nutrients such as nitrogen and phosphorus. For example, the application of compound fertilizer significantly increased the nitrogen and phosphorus content of coal mining collapse soil, increased soil bacterial diversity, and improved bacterial community structure (Meng et al 2023 ). Adding biochar can similarly alter the diversity of soil bacteria and fungi as well as community structure (Liu et al 2019 ).…”

Pseudomonas fluorescens with Nitrogen-Fixing Function Facilitates Nitrogen Recovery in Reclaimed Coal Mining Soils

“…Previous studies indicate that with the same soil type (calcareous brown soil), the nitrogen content of reclaimed soil in coal-mining areas is only 30.43% of that in cultivated soil in Shanxi Province [ 53 , 54 ]. The natural recovery rate of soil nitrogen is extremely slow [ 55 ], and the application of P. fluorescens can significantly increase the recovery rate of soil nitrogen.…”