重庆市农业环境及农产品污染评价研究

Assessment on Pollution of Agricultural Products and Agricultural Environment of Chongqing

根据现场采样及室内分析测试所得数据,对重庆市农业环境及农产品污染状况进行了评价研究。结果表明,农业环境与农产品质量呈现出多维特征,农区大气污染物SO2、NOx、TSP、F-之间均无显著相关,呈非正态分布,表明不同大气污染物的性质和特征差异较大,关联性差,来源复杂。土壤污染物的区域分布特征:Hg为城郊区>近郊区>远郊区,Cd、Pb为城郊区>远郊区>近郊区,As、Cr为远郊区>城郊区>近郊区。Hg、Cd、As、Cr两两之间均显著相关,呈正态分布,Pb无显著相关,呈非正态分布,表明土壤污染物的性质和特征具有共同性,关联性好,同源性高。农灌水污染物除Cr6+达显著相关呈正态分布外,Hg、Cd、Pb、As之间均无显著相关,呈非正态分布,表明农灌溉水污染物同水源关系密切。主要农产品水稻、玉米、蔬菜、茶叶、水果重金属赋存量因农产品种类、产地、重金属及含量不同差异较大。蔬菜对重金属Cu、Zn、Pb、Cd、Hg、As、Ni、Cr的富集能力差异显著,重金属元素之间存在Cr-Zn、Cd-Cr、Hg-Cr、Cu-As、Zn-As、Zn-Cd、Hg-Zn、Zn-Pb、As-Hg、As-Pb和Hg-Pb等相关系数显著的元素对,表明蔬菜的重金属含量不仅与土壤重金属含量有关,而且与蔬菜对各类重金属富集能力有密切的关系。

Agricultural environment, including soll and irrigation water, and farm products quality in Chongqing were monitored. The results showed that agricultural environment and farm products quality present multidimensional characteristics, and no significant correlations were found among the nlral atmospheric pollutants, SO2, NOx, TSP and F- that were abnormal distributed, indicating that the characters and traits of different atmospheric pollutants showed more diversities, less correla- tions and complex origins. The regional distribution characteristics of the soil pollutants were, Hg： suburb section〉suburban area〉outer suburban district; Cd and Pb： suburb section〉outer suburban district〉suburban area; As and Cr： outer suburban district〉suburb section〉suburban area. Hg, Cd, As, Cr showed normal distribution and there were significant correlations among them, but no significant correlation was existed between them and Pb that displayed abnormal distribution, indicating the characters of excellent correlations and high homologue of soil pollutants. Except Cr^6＋, Hg, Cd, As and Cr in agricultural irrigation water showed no significant correlations and abnormal distribution, indicating that the pollutants closely related the source of water. The heavy metal contents in main produces, rice, maize, vegetable, tea and fruit, differed with the kinds of crops, producing areas, heavy metals and their contents in soils. The enrichment ability of vegetable for Cu, Zn, Pb, Cd, Hg,As, Ni and Cr differed significantly, and there existed significant correlations between Cr-Zn, Cd-Cr, Hg-Cr, Cu-As, Zn-As, Zn-Cd, Hg-Zn, Zn-Pb, As-Hg, As-Pb and Hg-Pb, indicating that the heavy metal content in vegetable related with not only that in soil, but the enrichment ability of the vegetable for all kinds of heavy metals.