摘要
通过BCR3步提取法研究了江西省贵溪铜冶炼厂污染区水稻土中重金属的形态分布。研究表明,废渣场渗滤液污染区域(渣场区)的污染较污水灌溉污染区(污灌区)严重,渣场区土壤中Cu、Pb、Cd的含量高于污灌区,而污灌区土壤Ni含量较高。在表层(0～20cm)水稻土中,Cu以可氧化态为主,Pb以可还原态和可氧化态为主,Cd以酸溶态为主,Ni以残渣态为主,不同重金属元素的有效态所占总量百分比大小顺序是Cd>Cu>Pb>Ni。土壤重金属不同形态之间也呈现一定的相关性,说明Cu与Pb、Cd、Ni之间具有同源性。土壤pH主要影响了污灌区中Cu的形态分布,以及渣场区土壤酸溶态Ni的分布。土壤有机质含量对各重金属形态分布的影响不明显。
Distribution and forms of heavy metals in the topsoil （0-20cm） of polluted paddy soils around the Guixi Copper Smeltery, Jiangxi Province, were investigated. Using the sequential extraction procedure, four fractions of Copper （Cu）, Cadium （Cd）, Nickel （Ni）, lead （Pb） were determined in soils collected from two kinds of pollution regions, i.e. slag polluted region （SP in abbreviation） and wastewater irrigated region （WW）. The paddy soils in the research area were polluted mainly by Cu and Cd, and the pollution level was higher in SP than in WW. The mean contents of soil Cu, Cd and Pb was higher in SP than in WW, but that of Ni just contrary. In the surface soil layer （0 - 20 cm）, Cu was dominated mainly by the fraction of organic-matter-bound Cu; Cd by exchangeable and carbonate bound Cd; Pb by organic-matter-bound and Fe/Mn-oxide-bound Pb; and Ni by mineral Ni, i.e. residual Ni. The proportion of available fractions of soil heavy metals followed the sequence of Cd〉Cu〉Pb〉Ni. Besides, obvious correlations between various fractions of soil heavy metals, suggesting consanguinity of these metals. Soil pH influenced the distribution of soil Cu in WW, as well as the exchangeable and carbonates bound Ni in SP. However, soil organic matter content showed less influence.
出处
《土壤》
CAS
CSCD
北大核心
2007年第3期375-380,共6页
Soils
基金
国家自然科学基金项目(40271104)资助。
关键词
重金属
水稻土
化学形态
分级
影响因素
Heavy metal, Paddy soil, Chemical forms, Fraction, Influencing factor
