皖南茶园土壤重金属化学形态及其生物有效性  

Chemical Speciation and Bioavailability of Heavy Metals in Tea Garden Soils in South Anhui Province

作　　者：林跃胜[1] 方凤满[1,2] 魏晓飞[2] 

机构地区：[1]安徽师范大学生命科学学院,安徽芜湖241003 [2]安徽师范大学国土资源与旅游学院,安徽芜湖241003

出　　处：《水土保持通报》2014年第6期59-63,共5页Bulletin of Soil and Water Conservation

基　　金：安徽省自然科学基金项目"皖南山区土壤-茶树系统重金属迁移转化规律与健康风险分析"(11040606M30);安徽自然灾害过程与防控研究实验室基金项目

摘　　要：以皖南茶园为研究对象,通过Tessier连续提取分级法对茶园土壤重金属(Zn,Cu,Pb,Ni)全量及其化学形态进行了分析,利用活性态重金属占全量之比来评价其生物有效性。结果表明,皖南茶园土壤中Zn,Cu,Pb,Ni含量均未超过国家标准;除Zn外,其他元素均高出背景值,存在较明显的富集现象;土壤中4种重金属在5种形态上表现出不同的分布规律,Zn,Cu,Ni以残渣态为主,分别占总量的72.55%,90.00%和81.79%,而Pb以铁锰氧化物结合态为主,占总量的70.09%;Zn,Cu,Pb,Ni的活性态部分占全量比例分别为5.04%,1.51%,0.97%和0.23%,土壤重金属活性态部分与茶叶中重金属含量之间呈现正相关关系,且皖南茶区的茶叶重金属含量在限量值的安全范围内。Concentration and chemical speciation of heavy metals（Zn, Cu, Pb, Ni） in soil and tea collected from tea garden in South Anhui Province were analyzed by Tessier＇s sequential extraction method. Bioavail- ability of heavy metals were assessed by the ratio of active state to total amount. Results showed that concen- trations of Zn, Cu, Pb and Ni in the tea garden soils were lower than that of the national secondary standard. Cu, Pb, Ni concentrations exceed soil background value of South Anhui Province, which indicated there were obvious enrichment phenomenon. Zn, Cu, Ni mainly existed as residual speciation, accounted for 72.55%, 90.00%, 81.79% of the total respectively; Pb existed in iron and manganese oxides, accounted for 70.09% The active speciation（bioavailability） ratio of Zn, Cu, Pb, Ni were 5.04%, 1.51%, 0.97%, 0.23%, re- spectively. Active speciation of heavy metal in soil showed significantly positive correlation with the concen- tration of heavy metal in tea. Concentration of heavy metals is in the range of limited value and is safe in tea of South Anhui Province.

关 键 词：重金属 化学形态 生物有效性 皖南茶园土壤 

分 类 号：X53[环境科学与工程—环境工程]