玉米对有机氯农药污染土壤的修复潜力(英文)

目的]确定玉米对土壤中老化滴滴涕和六六六的累积、迁移和转化能力。方法]温室盆栽试验。取均匀掺入梯度浓度滴滴涕和六六六农药的科研土壤装盆,收集持续盆栽过程中不同时段的土壤和植物样品进行残留测试。结果]所选择的玉米植株在所设计的土壤污染浓度范围内具有宽域的滴滴涕和六氯环己烷清除能力,其茎秆、根系的生物浓缩系数分别介于0.004至0.027和0.036到0.097之间,但去除率均低于0.1,滴滴涕和六六六梯度处理间无显著差异。滴滴涕可通过被动吸附和主动吸收被玉米植体积累,且由还原性脱卤化介导,p,p’-DDT向p,p’-DDE转化。结论]玉米对土壤有机氯农药具有清除修复能力,且有机氯农药的对玉米脂肪的亲和力是影响其在植物体内的吸收和转运的主要因素之一。

Potentialities of Maize on the Removal of Organochlorine Pesticides from Contaminated Soils

In this paper, glasshouse experiments were conducted to determine the accumulation, distribution and transformation of DDTs and HCHs by maize under pot culture conditions. The culture soil was spiked with the organic pollutants and samples were collected in different durations. Analysis of the plants at harvest showed that the selected plant varied widely in their ability to remove and translo- cate DDTs and HCHs from the soil, the bioconcentration factor ranged from 0.004 to 0.027 for the shoot and from 0.036 to 0.097 for the roots, and the translocation factors were lower than 0.1 with variation between DDTs and HCHs, but no signifi- cant differences were observed. DDTs appeared to have accumulated by both pas- sive adsorption and active absorption, p,p＇-DDT and p,p＇-DDE were the major metabolite and the transformation was mediated by reductive dehalogenation, the affinity of the OCPs for lipids is one of the major factors affecting their uptake and translocation within the plants.