水质耦合模型在农药对土壤包气带污染中应用

在综合考虑农药类污染物在非饱和土壤环境中的水动力弥散、吸附解吸及微生物降解等环境行为的前提下,建立土壤中农药类化学污染物迁移的耦合动力学模型,模型中充分考虑了溶质在土壤固体骨架上非平衡吸附作用,并对农药阿特拉津在土壤中的运移过程进行了数值模拟,对模型中的几个重要参数(含水率、吸附速率和水动力弥散系数)进行了灵敏度分析;结果表明,土壤水分含量变化对农药类污染物质在环境介质中迁移转化起着重要作用.这对于定量化分析农药类污染物在土壤中迁移对地下水污染的潜在性影响提供了可靠的理论根据,同时可为现场农药环境污染评价提供技术支持.

Application of water solute coupled model to transportation of chemicals and pesticides on unsaturated zone pollution

On the premise of considering diffusion,absorption-desorption,distribution and biodegradation of chemical pollutants in solid-water environment,a water solute coupled model for chemical pollutant transportation and transformation has been developed based on the theory of soil solute transport,and the non-equilibrium adsorption is sufficiently described in the model.Numerical simulation for aldicarb transport in soil is presented.And the sensibility of some important parameters(water content,adsorption rate and hydrodynamic dispersion coefficient) is analysed.The results show that the variation of water content has an important part in pollutant migration and transformation,which provides theoretical evidence for quantitative analysis of potential effects of pesticide transport on groundwater pollution and by planners for making management decision.