Adaptive Development of Soil Bacterial Communities to Ecological Processes Caused by Mining Activities in the Loess Plateau, China

Abstract

Microorganisms are the driving force behind the circulation and transformation of the soil substance. The development of soil bacterial communities is critical for ecosystem restoration and evolution. In the Loess Plateau, coal mining activities have aggravated the deterioration of the fragile local ecological environment. The adaptive development of soil bacterial communities in response to different ecological processes caused by coal mining activities was explored through high-throughput sequencing technology and an ecological network analysis of the mining subsidence area of the Daliuta Coal Mine and vegetation rehabilitation area of the Heidaigou Coal Mine in the Loess Plateau. The results showed that while mining subsidence was inhibited, vegetation rehabilitation promoted the soil physicochemical properties. Soil organic matter, available phosphorus and available potassium in the subsidence area decreased significantly (P < 0.05), while soil organic matter, soil water, pH and EC in the vegetation rehabilitation area increased significantly (P < 0.05). The diversity index in the subsidence area decreased by about 20%, while that in the vegetation rehabilitation area increased by 63%. Mining subsidence and vegetation rehabilitation had a distinct influence on the molecular ecological networks of the soil bacteria, which tended to be more complex after the mining subsidence, and the number of connections in the network increased otherwise significantly enhanced interactive relationships. After the vegetation rehabilitation, the number of modules in the ecological network increased, but the contents of modules tended to be simpler. Soil bacterial communities adapted to the changes by changing the relationships between bacteria in response to different ecological processes. This study provides new insights into the monitoring and abatement of the damaged ecological environment in mines.

Driving force of soil microbial community structure in a burned area of Daxing’anling, China

“…Soil microbes have great complexity and diversity and are important for soil composition and nutrient cycling, and drivers of energy flow (Elsas and Boersma 2011) microbes play a critical role in plant growth and development, and in maintaining the productivity, functionality and stability of ecosystems (Felske et al 2000;Kuramae et al 2010). Since soil microbes are sensitive to changes in environment, they may be taken as indicators of soil restoration (Luo et al 2020).…”

“…The soil bacteria community structure, which was dominated by Acidobacteria, Proteobacteria, and Actinobacteria, changed to be dominated by Proteobacteria and Chloroflexi. As well, soil fungal community changed Significant changes could result from either natural or anthropgenic disturbances to ecosystems, for which different types of soil microbes display divergent coping mechanism due to their contrasting survival characteristics and environments, thereby further changing the microbial community structure (Luo et al 2020). Coal mining activities on the Loess Plateau have caused soil sedimentation which reduced soil bacterial diversity and resulted in significant changes in community structure (Luo et al 2020).…”

“…As well, soil fungal community changed Significant changes could result from either natural or anthropgenic disturbances to ecosystems, for which different types of soil microbes display divergent coping mechanism due to their contrasting survival characteristics and environments, thereby further changing the microbial community structure (Luo et al 2020). Coal mining activities on the Loess Plateau have caused soil sedimentation which reduced soil bacterial diversity and resulted in significant changes in community structure (Luo et al 2020). The removal of undergrowth vegetation caused chemical property changes in forest soils, including water contents, total nitrogen and phosphorus, hydrolyzed nitrogen, and available phosphorus, which in turn caused the reduction of relative abundance of soil bacteria of Proteobacteria, Planctomycetes, and Firmicutes, as well as a reduction in bacterial community diversity (Wu et al 2020).…”

“…Among various disturbances, fires have quite different effects on soil microbial community structure which are a continuous process (Villadas et al 2019;Luo et al 2020). Microbial communities are first directly affected by high temperatures and indirectly by changes in physical and chemical properties (Cai et al 2014;Wang et al 2020).…”

Ecological network analysis assesses the restoration success of disturbed mining soil in China

“…Moreover, key soil attributes are also modified after land reclamation. Reclaimed soils may present less soil organic matter, altered soil texture, lower soil water retention capacity, less soil nutrients, and lower native soil microbial diversity than the original soil (Ahirwal and Maiti, 2016;Luo, et al, 2020). All these changes may limit crop yield and land development following land reclamation .…”