珠江三角洲地区典型菜地土壤与蔬菜重金属分布特征研究

Contents of heavy metals in soil and vegetables at typical vegetable plot in the Pearl River Delta

通过对珠江三角洲地区的广州市、佛山市、江门市和惠州市典型菜地土壤和蔬菜中重金属(Pb、Cr、Cd、As和Hg)含量及其土壤中有效态(Pb、Cr、Cd)含量的调查,分析蔬菜重金属污染状况与土壤重金属含量的相关性,探讨了土壤重金属含量、有效态含量与土壤理化性质的相关性。结果表明,菜地土壤主要受Pb、Cd、Hg污染。Pb、Cd主要以轻度污染为主;而Hg污染在广州市菜地土壤以轻度污染和重度污染为主,佛山市菜地土壤以中度污染和重度污染为主,江门市和惠州市菜地土壤以轻度污染为主。蔬菜主要受Pb、Cd、Hg污染,少数蔬菜受到Cr污染,但并未检测出蔬菜受As污染。蔬菜中重金属含量与土壤中Pb、Cr、Cd的总量、有效态含量之间呈显著正相关关系,与土壤中As、Hg的总量无显著相关性。土壤中Pb、Cr含量与土壤有机质含量、黏粒含量、粉粒含量均达到显著相关。土壤中有效Pb与有效锰含量呈显著负相关关系,土壤中有效Cr含量与土壤粘粒含量、有效铁含量呈极显著正相关关系。

The heavy metals （Pb, Cr, Cd, As and Hg） total content of soils and vegetables and available content of soils （Pb, Cr and Cd） in the Pearl River Delta were determined to analyses the relationship between the pollution degree of vegetables and the heavy metals content of soil, the correlation of the heavy metals total content and available content, soil properties were investigated. The results show that the vegetable plot soil is mainly polluted by Pb, Cd and Hg. The soils were mainly polluted lightly by Pb, Cd; Hg pollution of vegetable plot soil is mainly light or severe pollution in Guangzhou city, light or mid pollution in Fushtm City, light pollution in Jiang men and Huizhou. Vegetables mainly affected by Pb, Cd, Hg pollution, a few vegetables contaminated by Cr, but not detected in vegetables contaminated by As. Heavy metals （Pb, Cr, Cd） content of vegetables have significantly positively correlated with total and available content of soils, while the heavy metals （As and Hg） content of vegetables have no significant amount of correlation with As, Hg total content of soil. Pb available content of soils was significantly negative related to Mn available content of soils, Cr available content of soils was significantly positive with soil clay content and Fe available content of soils.