贵州北部某铬渣场土壤重金属对酶活性和细菌群落的影响

Effects of Heavy Metals on Enzyme Activity and Bacterial Community in a Chromium Slag Field in Northern Guizhou

为了研究长期重金属污染下土壤酶活性和细菌门水平丰度对重金属的响应机制,该文采用电感耦合离子发射光谱仪、96微孔板荧光法、Illumina MiSeq高通量测序对土壤进行了分析,对某铬渣场内5个典型污染地区进行土壤重金属、酶活性、细菌的测量并分析,为矿区修复技术提供理论依据。结果表明,该研究区受锌、镍、铬这3种重金属的污染最为严重,受人为因素干扰最严重的区域是流域下游区域,其次为流域上游区域。蔗糖酶、脲酶酶活性在流域下游区域含量最高,重金属锌、铜、镍、锰、铬与蔗糖酶、过氧化氢酶、脲酶呈正相关关系,与酸性磷酸酶呈负相关关系。细菌的优势菌门为变形菌门、放线菌门、酸杆菌门和绿弯菌门,重金属与厚壁菌门、拟杆菌门、硝化螺旋菌门等呈正相关,绿弯菌门、厚壁菌门、拟杆菌门、硝化螺旋菌门在重金属污染严重区域丰度较高。综上所述,该研究区长期高浓度的重金属改变了土壤酶活性和厚壁、拟杆和硝化螺旋菌门对于重金属的耐受性。

This paper dealts with the study on the response mechanism of soil enzyme activity and bacterial phylum level abundance to heavy metal under the circumstances of long-term heavy metal pollution.The instruments including inductively coupled ion emission spectrometer,96 microplate fluorescence and Illumina MiSeq high-throughput sequencing were used to analyze the soil samples taken from five typical contaminated sites within a chromium slag field in northern Guizhou Province,involving heavy metals,enzyme activities and bacteria for the purpose of laying theoretical basis for the remediation technique of the mining area.As a result,the study showed that the study area was seriously polluted by three heavy metals the most,i.e.zinc,nickel and chromium,and the area most disturbed by human factors was in the lower reach of the river basin,followed by the upper reach.The activities of sucrase and urease were the highest in the lower reach of the river basin,and the heavy metals such as zinc,copper,nickel,manganese and chromium were positively correlated with sucrase,catalase and urease,and negatively correlated with acid phosphatase.The dominant bacterial phyla were Proteobacteria,Actinomycetes,Acidobacterium and Chlorobentomycetes;in addition,heavy metals were positively correlated with Firmicutes,Bacteroides,Nitrifying Spirals,etc.,and Chlorella,Firmicutes,Bacteroides,and Nitrifying Spirals were in higher abundance in the areas severely polluted by heavy metal.In summary,under the situation of heavy metals being in long-term high concentration had altered the soil enzyme activity,and the tolerance of Chloroflexi,Firmicutes,Bacteroidetes and Nitrospirae to heavy metal in this study area.