Taking Nanjing as the research area and three DDTs isomers as the study objects, a level Ⅳ fugacity model of Nanjing area was established.The model was used to simulate the concentrations distribution and transfer fluxes of three DDTs isomers in air, water, soil, sediment, and plants of study area.Moreover, taking the p, p'-DDT as an example, the model output concentrations were 9.72× 109mol/m3 in water, 9.87× 105mol/m3 in soil, 4.61 × 106mol/m3 in sediment, and 8.28×106mol/m3 in plant, respectively, which were in good agreement and had same order of magnitude with the observed concentrations with 2.69×109mol/m3 in water, 2.41×104mol/m3 in soil, 8.15×106mol/m3 in sediment, and 2.43×105mol/m3 in plant in research area, respectively.The established model was applicable in Nanjing region.In addition, the model was also applied for predicting the concentration variations of each environmental medium in Nanjing from 2000 to 2050.The transfer processes in Nanjing region were similar to those in Hangzhou, in which the main transfer processes in order were as follows: the air-soil deposition, water-sediment deposition, air-water deposition,soil-water outflow(soil erosion), water-air diffusion, but were far different from those in North China, which were the main air-soil deposition, air-water deposition or water-air diffusion.From this study, we could also deduce that agricultural application in early years were the most main source of DDTs in Nanjing area, occupying 97.69％ of the total amount in the environment.The degradation in air and soil were the major way of DDTs disappearing from the study area,accounting for 95.44％～95.96％ , another disappearing ways included the degradation in water, sediment and plant as well as outflow from air and water.After several decades, the biggest bulk sinks were soil and sediment occupying 99.28％,meanwhile the concentration in plant showed a dramatic decline.%以DDTs(p,P'-DDT,o,P'-DDT,p,p'-DDD)为研究对象,建立了南京地区DDTs的阴级逸度模型,模拟计算了DDTs研究区域环境大气、水体、土壤、沉积物和植物相中的浓度及相间迁移通量.结果表明,以p,p'-DDT为例,在水、土壤、沉积物、植物相中的模拟输出浓度分别为9.72×109,9.87×105,4.61 ×106,8.28×106mol/m3.与当地对应环境相中的DDTs实测浓度2.69×109,2.41×104,8.15×106,2.43×105mol/m3在数量级上吻合较好,验证了模型在南京地区的适用性,井预测了2000～2050年间DDTs在备相中浓度的动态变化情况.比较了各城市间多介质环境迁移特征,结粜显示,南京地区的DDTs相间迁移过程与杭州地区近似,主要迁移过程依次为:气-土沉降,水-沉积物相沉降,气-水沉降,土-水流失(土壤侵蚀),水-气扩散.但不同于我国北方地区的以气-土沉降,气-水沉降或水-气扩散为主.南京地区早期的农药施用是DDTs的主要来源,占总输入量的97.69%,大气和土壤中的降解则是DDTs的主要消失途径,占总降解量的95.44%～95.96%,其余4.04%～4.56%通过水、沉积物、植物降解和气/水平流输出而消失.今后几十年中,土壤和沉积物成为DDTs的主要储库,占总量的99.28%左右,并凡植物相中的浓度已大幅下降.
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