岷江下游(五通桥段)土壤污染特征及生态风险评价  

Characteristics and Ecological Risk of Soil Pollution in the Lower Reaches(Wutongqiao Section)of Minjiang River

作　　者：简毅[1] 杨万勤[1] 张健[1] 杜波[1] 林静[1] 王奥[1] 周利强[1] 

机构地区：[1]四川农业大学林业生态工程重点实验室,四川雅安625014

出　　处：《农业环境科学学报》2009年第2期256-262,共7页Journal of Agro-Environment Science

基　　金：国家"十一五"重大科技支撑计划课题(2006BAC01A11);国家自然科学基金(30471378;30771702);四川省青年科技基金项目(07JQ0081);四川省重点科技攻关项目(2007NGY006);四川农业大学"人才引进"项目

摘　　要：为了解岷江下游(五通桥段)土壤污染特征及其生态风险,采用野外采样及室内测试方法分析了岷江下游(五通桥段)103个土壤样品中的农药残留量和重金属含量。结果表明,全部样品中六六六(HCHs)含量符合国家二级标准(500μg.kg-1),大部分样品中滴滴涕(DDTs)含量符合国家二级标准,有机磷农药(OPPs)杀螟硫磷(60.40%)和溴硫磷(55.45%)超标率较高,重金属Cd的地积累指数高达2.79。有机氯农药(OCPs)禁用20a后在区内的降解程度较高,OPPs在土壤中的大量残留是由于农药的无序使用,外源输入是导致重金属污染的主要原因。区内农药残留和重金属污染范围广,复合污染较严重,存在较大的生态风险。Soil pollution characterized by residual pesticides and heavy metal contamination is limiting the agricultural clean production and still threatening the health and survival of human beings, as a consequence of which much attentions have been given to the pollution characteristics and the ecological risks of residual pesticides and heavy metal in soils of different regions worldwide. As yet, little is known about the characteristics of soil pollution and its ecological risk in the lower reaches of Minjiang River which plays an important and irreplaceable role in agricultural production and aquatic environment safety since there is lack of the simultaneous study of soil residual pesticides and heavy metals, which is difficult to make needs of agricultural clean production and environmental protection. The concentrations of residual pesticides and heavy metals in 103 soil samples were therefore analyzed in order to obtain an understanding of the characteristics of soil pollution and ecological risk in the lower reaches（Wutongqiao section）of Minjiang River. Benzene hexachloride（ HCHs ）concentration in all soil sam- ples was in the range of the 2nd level of National Soil Environment Quality Standard （GB 15618-1995 ）（500μg·kg-1 ）. Simi- larly, dichlorodiphenyhrichloroethane （DDTs）concentration in 96% soil samples accorded with the 2st level of National Soil Environment Quality Standard. Fenitrothion and bromohos were detected in 60.4% and 55.5% of all samples, which were both higher than those of the rest of organophosphorus pesticides （OPPs）. The geoaccumulation index of Cd reached 2.19. After OCPs had been forbidden for twenty years, its degradation was still salient in the region. A great deal of OPPs residuals were found in the soil, because of the abuse of OPPs. The sources of heavy metals were still also distinct. The potential ecological risk of pesticide residuals and heavy metals in soil was found in study area.

关 键 词：岷江下游 土壤 农药残留 重金属 复合污染 生态风险评价 

分 类 号：X825[环境科学与工程—环境工程]