中文摘要：

以硫丹为研究对象,利用三级多介质逸度模型,对硫丹在半干旱的兰州河谷盆地大气、水体、土壤、沉积物和植物相中的浓度分布进行模拟研究;对硫丹在研究区环境多介质间的迁移通量进行分析,确定其在环境中的主要迁移过程;并结合实际监测数据,对模型的可靠性进行验证;此外,还对除常数之外的20个模型参数进行灵敏度分析,并对较高的模型灵敏度影响因素进行不确定性分析.研究结果表明：土壤、植物和沉积物相是硫丹在兰州河谷盆地环境污染的主要储库;大气平流输入和农药施用是研究区硫丹的主要输入源,沉积物降解和大气平流输出为研究区的主要消耗和输出途径;亨利常数、辛醇-水分配系数等化合物理化性质参数,以及沉积物、土壤有机碳含量等环境参数对模型的灵敏度影响比较显著;模拟浓度与实测浓度相差在一个数量级之内,吻合较好,表明建立的三级多介质逸度模型适用于半干旱的兰州河谷盆地α-硫丹和β-硫丹的环境多介质迁移及归趋行为模拟.

英文摘要：

Taking Lanzhou as the study area, a level Ⅲ fugacity model was applied to simulate the concentration distribution of two endosulfan isomers in five environmental compartments including air, water, soil, sediment and vegetation. Meanwhile, the transfer fluxes between different compartments were analyzed in order to identify main transfer process. In addition, the reliability of this model was studied by comparing modeling results with observational data. For the model uncertainty, twenty parameters of the model were tested and the key parameters were identified using sensitivity analysis, and the uncertainty of these key parameters was estimated. The study results showed that the soil, vegetation and sediment compartments were the main reservoirs of endosulfan in Lanzhou area. Furthermore, the main input sources of endosulfan in the study area were the air inflow and use of pesticides, while the soil degradation and air advection outflow were the major routes for endosulfan depletion in the study area. The study results also indicated that the physical and chemical properties of endosulfan, such as Henry＇s Law Constant and KOW, as well as the environmental parameters including organic carbon content of sediment and soil had a significant influence on the model sensitivity. The reliability of the model was verified by the agreement between calculated and measured concentrations with the log-scale differences within an order of magnitude. This case study showed that the developed model was suitable for simulating the multimedia transfer and fate of endosulfan in the semi-arid Lanzhou area.