研究了陕西省铜川煤矿矿区的重金属污染状况以及不同程度的重金属污染对土壤微生物代谢、微生物群落功能以及土壤酶活性的影响.结果表明:铜川矿区土壤中重金属Cu、Zn、Cd、Pb全量及有效量均显著高于非矿区土壤,其中Cd污染最为严重.采用Biolog方法结合主成分分析和聚类分析发现,随着污染程度的增加,不同土壤微生物群落间的代谢特征发生显著变化,而且这种变化主要体现在糖类和氨基酸类碳源的利用差异.在轻度、中度污染情况下,土壤微生物群落对碳源的利用表现出激活效应;而在重度污染的情况下,土壤微生物群落对碳源的利用表现出抑制效应.随着污染程度的增加,脲酶、蛋白酶、碱性磷酸酶和过氧化氢酶的活性均呈现降低的趋势,矿区土壤脲酶、蛋白酶、碱性磷酸酶和过氧化氢酶活性分别是非矿区土壤中相应酶活性的50.5%~65.1%、19.1%~57.1%、87.2%~97.5%、77.3%~86.0%;蔗糖酶和纤维素酶在中等污染程度以下的土壤中表现为激活效应,而在重度污染的土壤中表现为抑制效应.
This paper studied the metabolism of soil microbes,functions of soil microbial communities,and activities of soil enzymes in a coal mining area of Tongchuan.In the coal mining area,the concentrations of soil Cu,Zn,Cd,and Pb were significantly higher than those in the non-mining area,of which,Cd contributed most to the heavy metals pollution.By adopting Biolog method combining with principal component analysis(PCA) and cluster analysis,it was found that the metabolic characteristics of different soil microbial communities varied significantly with increasing soil heavy metals pollution,and the variation was mainly manifested in the metabolic patterns of carbon sources such as saccharides and amino acids.In slightly and moderately polluted soils,the utilization of carbon sources by soil microbial communities was activated;while in heavily polluted soils,the carbon sources utilization was inhibited.The activities of soil urease,protease,alkaline phosphatase,and catalase all tended to decline with intensifying soil heavy metals pollution.The soil urease,protease,alkaline phosphatase,and catalase activities in the coal mining area were 50.5%-65.1%,19.1%-57.1%,87.2%-97.5%,and 77.3%-86.0% higher than those in the non-mining area,respectively.The activities of soil sucrase and cellulase were activated in slightly and moderately polluted soils,but inhibited in heavily polluted soils.