酸性矿山废水对稻田土壤微生物菌群结构的影响

为探究酸性矿山废水(AMD)对稻田土壤微生物群落结构的影响,通过取自矿区受AMD污染和未受污染的稻田土壤进行微宇宙灌溉模拟实验,研究了AMD污染过程中土壤理化性质和微生物群落的变化,同时建立环境条件变化引起土壤微生物群落结构改变的相关性关系.结果表明,受AMD污染的土壤中SO_4~(2-)、Cd、Zn含量显著上升,土壤酸化且土壤中细菌群落的多样性下降;而恢复清洁水灌溉可提高土壤细菌群落的多样性,有利于修复AMD的污染.采用高通量测序技术分析了不同处理稻田土壤中微生物群落在门和属分类水平上的相对丰度分布变化,冗余分析(RDA)表明,土壤pH和重金属(Pb、Cu)含量是影响稻田土壤微生物群落结构的主要环境因子.研究结果不仅有助于进一步揭示AMD污染、土壤因子与土壤微生物群落的相互关系,同时可为恢复AMD污染农业土壤提供理论依据.

Responses of microbial communities in paddy soils to the intrusion of acid mine drainage

In this study, laboratory simulation experiment was performed to evaluate the effect of AMD intrusion on paddy soil microbial communities. The alteration of microbial communities in long-term AMD-polluted and unpolluted soils under continuous AMD irrigating was comprehensively studied. Meanwhile, soil physicochemical properties were also regularly measured to determine their correlation with soil microbial community. The results indicated that AMD intrusion significantly increased the content of SO₄^2-, Cd and Zn in soil, acidified the soil and decreased the diversity of bacterial community. While clear water irrigation was beneficial to the remediation of AMD contaminated soils and increased the diversity of bacterial community. A comprehensive survey of taxa distribution on the phylum and genus level of microbial community has been investigated by high-throughput sequencing technique. Results of RDA analysis showed that soil pH and heavy mental (Pb and Cu) content were the key factors influencing the community structure. Results also elucidate the relationship among AMD pollution, soil factors and soil microbial communities, and are useful for developing strategies to remediate AMD pollution in agriculture soil.