长期污水灌溉条件下土壤重金属形态及生物活性的研究  

Chemical Fractions and Bioavailability of Heavy Metals in Long-Term Sewage-irrigated Soils

作　　者：马祥爱[1] 秦俊梅[1] 冯两蕊[1] 

机构地区：[1]山西农业大学资源环境学院,山西太谷030801

出　　处：《中国农学通报》2010年第22期318-322,共5页Chinese Agricultural Science Bulletin

基　　金：山西农业大学校内青年基金项目(200207);国家自然科学基金资助项目(40071077)

摘　　要：通过野外调查和试验分析,对孝义市污灌区土壤中Ni、Cr、Pb、Cu、Zn、Cd6种重金属的含量、形态分布和生物活性进行了研究。结果表明,孝义市污灌区土壤中重金属都未超过国家二级标准,但Ni、Cr、Pb比当地背景值都有所增加。土壤中重金属各形态的分布存在很大差异。Ni、Cr、Zn主要以残渣态的形式存在。Pb主要以残渣态和铁猛氧化态存在。Cu主要以残渣态和有机结合态的形式存在。Cd在残留态中比例最小,碳酸盐结合态和交换态含量比例很高。与对照相比,污灌降低了重金属残留态所占比例,改变了土壤中重金属存在形态,提高了重金属的生物有效性和迁移能力。污灌区土壤中重金属活性系数的大小顺序为:Cd>Pb>Cu>Cr>Zn>Ni;迁移系数的大小顺序是:Pb>Cd>Cu>Cr>Zn>Ni,土壤中Cd、Pb的活性最高,生态污染风险最大,应引起足够重视。Fraction and bioavailability of heavy mental in sewage-irrigated soils of Xiaoyi were investigated.The results showed that the total contents of Ni,Cr,Pb,Cu,Zn and Cd do not exceeded the maximum permissible limits set by state environmental protection agency （SEPA） for soils in China,but the concent of Ni,Cr and Pb has increased compared with the local soil background value.There are significant differences in fractions of heavy metals in sewage-irrigated soils.Further,the residual fraction was the predominant fraction for Ni 、 Cr and Zn.Pb was dominated by the residual fraction and iron-manganese oxides fraction,and Cu was dominated by organic fraction and residual fraction,For cadmium,mainly fraction were exchangeable and carbonate bound forms and the residual form was limited.compared with the non sewage-irrigated soils,sewage irrigation increased the bioavailability of heavy metals and changed the Chemical fractionation of heavy mental.The availability of heavy metals in sewage-irrigated soil was as order Cd Pb Cu Cr Zn Ni,and the mobility followed Pb Cd Cu Cr Zn Ni,respectively.The bioavailability of Cd and Pb were much more higher than other heavy metals.

关 键 词：污水灌溉 土壤重金属 形态分析 生物活性 TESSIER连续提取法 

分 类 号：X131.1[环境科学与工程—环境科学]