中文摘要：

以我国东北典型污灌区为研究区域,获取相关数据及模型参数,并应用逸度方法探讨了有机氯农药的土-气交换行为及其分馏效应。研究结果表明,在土壤有机质含量一定的情况下,日均温度最大时有机氯农药六六六（HCHs）和滴滴涕（DDTs）之间土-气分配系数（KSA）的差异比日均温度最小时高出一个数量级,HCHs比DDTs更容易挥发重新释放进入环境中而进行二次分配,土壤有机质质量分数每提高1%而引起的KSA值的变化率不同,且这种变化会随着有机质质量分数的提高而趋于平稳;辛醇-气分配系数（KOA）与土-气交换逸度分数ff呈负相关关系,当土壤有机质质量分数为1%、2%和3%时,其相关系数分别为-0.743（P〈0.05）、-0.763（P〈0.05）、-0.776（P〈0.05）;应用土-气浓度比（Cs/a）,进一步判定土壤浓度和大气浓度在其他参数不变的情况下,将会对HCHs及DDTs的土-气交换行为产生影响;HCHs与DDTs的初次分馏及二次分馏效应进一步说明土壤性质及其自身的理化性质均会对分馏效应产生影响。

英文摘要：

A typical irrigation area was selected as objective study area which has more than forty years history with wastewater irrigation in northeast China. Acquiring relevant data and model parameters, the soil air exchange of organochlorine pesticides and its fractionation effect were deeply disscussed with application of fugacity approach. The results show that, in the certain cases of soil organic matters, the difference of soil - air partition coefficient （KsA） between HCHs and DDTs has one order of magnitude at daily average maximum temperature higher than at daily average minimum temperature; HCHs released into environment for secondary distribution more easily than DDTs. The rate of change of KsA value is different when every 1% enhanced in soil organic matter and gradually stabilizing with enhanced soil organic matter content. There is a negative correlationship between octanol-air partition coefficient （KoA） and fugacity fraction （fs） of soil - air exchange, the correlation coefficients are： R = -0.743 （P〈0.05）, R= -0.763 （P〈0.05）, R= -0.776 （P〈0.05） when soil organic matters are 1%, 2% and 3%, respectively. Application of ratio between soil and air concentration （Ca/a）, in the constant cases of other parameters, the soil and air concentration will affect the soil - air exchange of HCHs and DDTs. The primary and secondary fractionation effect of HCHs and DDTs further suggested that the soil properties and physical chemical properties will affect their fractionation effect.