基于污染指数与ArcGIS的聊城市耕地OCPs污染研究

按8 km×8 km网格将聊城市耕地划分为136个采样点,调查六六六(BHCs)、滴滴涕(DDTs)、艾氏剂、狄氏剂、异狄氏剂、六氯苯和七氯等7种有机氯农药(OCPs)的残留状况。采用单因子污染指数和综合污染指数法进行污染评价,以此判断OCPs的污染程度。对7种OCPs在各样点中的含量进行差异分析,并应用ArcGIS8.3,以污染评价结果为数据支持,进行OCPs污染空间分布研究。结果表明,聊城市OCPs污染程度依次为DDTs>狄氏剂>七氯>艾氏剂>BHCs>异狄氏剂>六氯苯,总体变异程度依次为DDTs>狄氏剂>异狄氏剂>BHCs>七氯>六氯苯>艾氏剂。各OCPs空间分布没有固定的变化趋势;各采样点综合污染水平存在地域差异,以临清市污染最为严重,其他各县市污染较轻。

Research on OCPs Pollution in Arable Land from Liaocheng Based on Pollution Index and ArcGIS

The residues of BHCs,DDTs,aldrin,dieldrin,endrin,hexachlorobenzene and heptachlor in 136 soil samples had been monitored from Liaocheng. The single-factor pollution index and integrated pollution index were used to evaluate the organochlorine pesticides(OCPs)pollution,and the polluted degree had been ensured. The variance in all samples of all OCPs had been analyzed,then ArcGIS8.3 had been used to study the spatial distribution of OCPs based on the evaluation data. The result showed that the order of the pollution degree of 7 OCPs was: DDTs>dieldrin>heptachlor>aldrin>BHCs>endrin>hexachlorobenzene;the variation degree was: DDTs>dieldrin>endrin>BHCs>heptachlor>hexachlorobenzene>aldrin,there was not a stable tendency in spatial distribution;there was regional diversity of comprehensive level of pollution in all soil samples,the OCPs pollution was the most remarkable in Linqing,and was generally slight in the other counties.