大气环流影响下有机氯农药传输的推断

在四川盆地西缘到川西高原建立有机氯农药传输剖面,采集大气颗粒物,大气干湿沉降以及对应点位土壤样进行分析测试。研究表明各种HCH异构体最高含量均位于研究区海拔的分界点位置上。HCHs各同分异构体中-HCH含量最高,说明研究区没有新的HCH农药输入。在土壤和大气降水含量中,低海拔地区明显高于高海拔地区。高海拔地区有机氯农药的来源大多源自大气颗粒物和大气干沉降。通过大气环流平均流场图,结合地形因素,各种因素综合影响着有机氯农药的远程传输,通过各采样点不同介质中有机氯农药的含量,可以较为准确的判断出有机氯农药大气传输的具体形式。在不同的月份,因大气环流方向的变化,有机氯农药大气传输的来源也不同,不能简单的认为从低海拔地区传输到高海拔地区。高原区有机氯农药的源汇也会因大气环流的变化而发生转换。

Inferring Atmospheric Circulation Impact of Organochlorine Pesticides Transmission

A transmission profile of organochlorine pesticides was established in the western margin of Sichuan Basin to western Sichuan plateau,atmospheric particulate matter,atmospheric dry and wet deposition as well as corresponding point of soil samples for studies were collected.Results showed that the highest content of HCHs was located on the elevation boundaries of the study area.β-HCH content is the highest in the study area,which indicated that there are no new HCH pesticide input.Content of the soil and atmospheric precipitation in low-lying areas is significantly higher than that in high altitude area.Sources of organochlorine pesticides in high altitude area are mostly derived from atmospheric particulate matter and atmospheric dry deposition.A variety of factors affect the long distance transmission of organochlorine pesticides,and the content in different media of each sample point can determine the form of atmospheric transport of organochlorine pesticides.In different months,due to the change of atmospheric circulation direction,the source of organochlorine pesticides in the atmospheric transmission is also different,and it can not be simply think that it is from low-lying areas to high altitude area.Source and sink of organochlorine pesticides in plateau area would take place because of change of atmospheric circulation.