长三角和珠三角农业土壤中铅、铜、镉的化学形态与转化  

Chemical forms and transformations of Pb,Cu and Cd in agricultural soils of Changjiang and Zhujiang deltas.

作　　者：方利平[1] 章明奎[1] 陈美娜 黄昌勇[1] 

机构地区：[1]浙江大学环境与资源学院资源科学系,杭州310029 [2]绍兴市农业科学研究院,绍兴312003

出　　处：《中国生态农业学报》2007年第4期39-41,共3页Chinese Journal of Eco-Agriculture

基　　金：国家重点基础研究发展规划(973)项目(2002CB410804);国家自然科学基金项目(40471064)资助

摘　　要：研究了重金属Pb、Cu、Cd在长江三角洲和珠江三角洲土壤中的转化及不同Pb、Cu、Cd负荷水平对土壤重金属形态的影响。结果表明:未明显污染土壤中重金属主要以残余态为主,可提取态组分的比例Cd>Cu>Pb,但不同土壤之间有较大变化;随着土壤重金属负荷的提高,土壤中交换态重金属的比例增大,残余态比例下降,有效性提高,对环境威胁增大;当重金属加入量较低时,重金属优先向氧化物结合态、有机质结合态转化,而当加入量较高时,向交换态和碳酸盐结合态转化的比例明显增加;pH和土壤组分对重金属在土壤中的转化有显著影响,土壤pH下降可使交换态Cd、Cu、Pb的比例递增。The transformation processes of Pb,Cu and CA in ten agricultural soils from Changjiang and Zhujiang deltas were characterized and the effect of Cd,Cu and PL loads on their chemical forms in the soil studied. Results show that a major fraction of heavy metals in unpolluted soils is in residual form. The proportion of extractable fraction of the heavy metals varies with soil type,but follows a general order of Cd〉Cu〉 Pb. With increasing loads of heavy metals in the soils,the proportion of exchangeable form of the metals increases while that in residual form decreases,leading increased availability and impact of the metals on the environment. When heavy metals are added in low levels,the metals are preferentially transformed into oxides and organic matter fraction bonds. However, the higher proportion of metals leads to exchangeable and carbonate fraction bond transformation. The proportion of exchangeable Pb, Cu and CA fractions in the soil increase with decreasin4g pH.

关 键 词：长三角 珠三角 农业土壤 重金属 形态 转化 

分 类 号：S158[农业科学—土壤学]