泉州走马埭典型土壤重金属的赋存形态分析

采用改进的Tessier连续萃取方法研究了泉州走马埭国家农田示范保护区典型土壤中重金属(Cr、Ni、Cu、Zn、Cd、Pb)的化学形态分布,通过土壤重金属的赋存形态分析比较了6种重金属的生物可利用性。研究结果表明,土壤中不同重金属元素化学形态分布具有不同的特点:Cr和Ni主要以残渣态存在,其余形态所占的比例很小;Cu以残渣态含量最高,碳酸盐结合态含量最低;Zn以残渣态为主,可交换态含量最低;Cd以可交换态和碳酸盐结合态为主,水溶态含量最低;Pb以残渣态和铁锰氧化物结合态为主,水溶态含量最低。土壤中除Cd外,Zn、Cu、Cr、Pb、Ni在正常自然条件下相对比较稳定。

Forms of Heavy Metals in the Typical Soils of Zoumadai of Quanzhou

The modified Tessier sequential extraction method was adopted to study chemical speciation of heavy metal elements (Cr,Ni,Cu,Zn,Cd,Pb) in the typical soil of Zoumadai,a state agricultural base in Quanzhou,and comparison was made between the heavy metals in biological availability. Results showed that Cr and Ni were dominated by residual form,and rarely existed in other forms; Cu and Zn were also mostly in the residual from,while the least in the exchangeable fraction for Zn,and in the carbonate fraction for Cu; Pb existed mainly in residual and Fe-Mn oxides forms,while Cd in exchangeable and carbonate forms. All the heavy metals,except for Cd,were comparatively stable under normal natural conditions.