煤矿区土壤细菌群落结构及其对不同复垦模式的响应

Soil bacterial community structure in coal mining area and its response to different reclamation patterns

科学揭示不同复垦模式土壤细菌群落稳定性及其潜在互作关系对于复垦土地差异化管理及可持续利用至关重要。本文以挖深垫浅、煤矸石充填和粉煤灰充填3种模式复垦土壤为研究对象,基于高通量Illumina Miseq 16S rRNA测序技术,采用方差分析、Spearman相关性等分析方法,研究不同复垦模式下的土壤细菌群落结构和多样性。通过构建分子生态网络模型,揭示不同复垦模式下土壤细菌群落的稳定性及菌群间潜在互作关系,明晰对细菌群落结构稳定性起关键作用的微生物种群。结果表明:①不同复垦模式土壤细菌群落的多样性与丰富度水平有显著差异(P<0.05),均表现为挖深垫浅>煤矸石充填>粉煤灰充填;不同复垦模式土壤细菌群落组成相似,变形菌门、酸杆菌门、放线菌门和拟杆菌门是所有模式土壤中的优势菌门,在各复垦模式土壤细菌群落中的占比之和均达70%以上。②不同复垦模式下土壤细菌群落的显著影响因子不同,部分优势细菌门与影响因子间的变化趋势不同,有机质含量是影响挖深垫浅复垦土壤细菌群落组成的主要影响因素,pH是影响煤矸石与粉煤灰充填复垦土壤细菌群落组成的主要影响因素。③挖深垫浅复垦土壤细菌网络复杂,群落联系紧密,能更好地传递物质、能量和信息;煤矸石充填复垦土壤细菌网络内部节点间的连通度低,但菌群信息交换速度慢,拥有4个关键节点,网络相对稳定;粉煤灰充填复垦的土壤细菌网络规模最小,节点连通度不高,在外界环境发生变化时反应快,网络稳定性最差。3种复垦模式土壤细菌群落间关系均以协同合作为主导,煤矸石充填复垦土壤细菌群落间的协同合作关系占比最高。本文揭示了3种不同复垦模式下土壤细菌群落结构与分子生态网络差异,研究结果可为高潜水位采煤塌陷区土地复垦模式的优选以及人为干预方式的选择提供支撑。

Scientific revelation of soil bacterial community stability and potential interactions between different reclamation models is essential for differentiated management and sustainable use of reclamation land.The diversity of soil bacterial communities under different reclamation modes was studied by analysis of variance and Spearman correlation based on high-throughput Illumina Miseq 16S rRNA sequencing technology.By constructing a molecular ecological network model,the stability of soil bacterial communities and the potential interaction relationships between microbiota under different reclamation modes were revealed,and the microbial populations that play a key role in the stability of bacterial community structure were clarified.The results showed that:①There were significant differences in the diversity and richness of soil bacterial communities in different reclamation models(P<0.05),which were manifested as deep digging of shallow>gangue filling>fly ash filling.The composition of soil bacterial communities in different reclamation models was similar,Proteobacteria,Acidobacteria Actinomycetes and Bacteroides were the dominant phylum in all model soils,with their combined proportions accounting for over 70% of the soil bacterial communities in each reclamation mode.②The significant influencing factors on soil bacterial communities varied among different reclamation models,and the change trend between some dominant bacterial phyla and influencing factors was different.Organic matter content was identified as the main influencing factor for deep digging and shallow reclaimed soil bacterial community composition,while pH played a major role in the composition of soil bacterial communities in reclaimed soil filled with gangue and fly ash.③The soil bacterial networks in the deep digging and shallow reclamation models are complex,with closely connected communities that facilitate the transmission of substances,energy,and information.In contrast,the connectivity between nodes in the bacterial network of gangue filling soil is low,but the exchange of information within the network is slow.It has four key nodes and relatively stable network structure.The soil bacterial network of fly ash filling reclamation is the smallest,with low node connectivity.However,it responds quickly to changes in the external environment,but has the poorest network stability.The relationships between soil bacterial communities in the three reclamation models are characterized by collaborative cooperation,with the highest proportion of synergistic cooperation observed in gangue filling reclamation.This study reveals the differences in soil bacterial community structure and molecular ecological networks under different reclamation modes,providing support for the optimization of land reclamation strategies and the selection of intervention methods in areas with high groundwater levels caused by coal mining subsidence.