铁矿区重金属污染对土壤微生物代谢活性的影响  

Impacts of Long-Term Heavy Metal Pollution on Microbial Metabolic Activity in Iron Mine Soil

作　　者：邢奕[1] 张莹莹[1] 司艳晓[1,3] 洪晨[1,2] 王康[1] 刘敏[1] 赵晓明[1] 

机构地区：[1]北京科技大学土木与环境工程学院,北京100083 [2]中国科学院生态环境研究中心,北京100085 [3]清华大学环境学院,北京100084

出　　处：《环境科学研究》2015年第12期1879-1886,共8页Research of Environmental Sciences

基　　金：国家自然科学基金项目(41273091);北京市科技新星计划项目(Z111106054511043)

摘　　要：以北京市密云水库上游某铁矿区为研究对象,利用比色法、微量热法对铁矿区内各采样点土壤酶活性及其微量热代谢活性指标进行分析,以探究不同区位重金属污染下土壤微生物代谢活性的变化.结果表明：各采样点土壤中w（Cu）、w（Cd）、w（Zn）、w（Cr）均超过北京市土壤相应背景值.在重金属污染程度较低的S6、S7、S8采样点,土壤脲酶、FDA酶（荧光素二乙酸脂酶）活性均较高,分别为0.64、1.22、0.64 mg/g和1.25、2.84、1.45μg/g.微量热代谢活性指标中,k（生长速率常数）在污染程度较低处的值均较高,而重度污染区域的S1、S4采样点的k为0.相关性分析显示,k是反映微量热中代谢热活性的最具代表性指标.RDA（冗余度分析）结果显示,w（Cd）、w（TN）、w（AP）、w（TOC）、内梅罗污染指数及w（Cu）是影响k、Pm（最大热输出功率）的主要因素.Cd、Cu污染抑制了土壤微生物的代谢活性,不同代谢活性指标对重金属的敏感程度表现为k最强,Pm、脲酶活性、FDA酶活性次之.To examine the spatial changes of microbial metabolic activity in an iron mine upstream from Miyun Reservoir,the microbial activity and microcalorimetry heat metabolism activity index were applied in the method of calorimety and microcalorimetry from different sample sites. The results showed that： w（ Cu）,w（ Cd）,w（ Zn） and w（ Cr） of different soil sampling sites were higher than the Beijing local soil background values. In samples with relatively low degree of heavy metal pollution（ S6,S7 and S8）,the urease activity was 0. 64,1. 22 and 0. 64 mg/g,and the FDA enzyme activity was 1. 25,2. 84 and 1. 45 μg/g,respectively,higher than other points. The microcalorimetry heat metabolism activity index showed that,in light pollution,the constant growth rate of k was very high,while in seriously contaminated sites S1 and S2,the k values approached zero. Correlation analysis showed that k was the most representative index to trace the metabolic heat activity. The RDA results indicated that w（ Cd）,w（ TN）,w（ AP）,w（ TOC）,Nemerow and w（ Cu） were identified to be the major influential environmental factors driving changes occurring in the metabolic activity k,FDA,urease and Pm. The microbial metabolic activity was inhibited by Cd and Cu. k was the metabolism activity index most sensitive to heavy metals,while Pm,urease activity and FDA enzyme activity took second place.

关 键 词：重金属 脲酶活性 FDA酶活性 代谢活性 

分 类 号：X53[环境科学与工程—环境工程]