北京城市雨水、树冠水和地表径流中有机氯农药的污染特征

对北京降雨过程中雨水、树冠水、地表径流等介质中有机氯农药(OCPs)的污染特征进行了研究,研究的污染物包括六氯苯(HCB)、六六六(HCH)和滴滴涕(DDT)。结果显示,在雨水、树冠水和地表径流中,HCH含量最高(几何平均浓度分别为11.1、21.6和25.1 ng/L),其次是HCB(几何平均浓度分别为3.71、3.54和5.91 ng/L)和DDT(几何平均浓度分别为2.64、4.66和10.6 ng/L)。对地表径流样品中所测的OCPs组分浓度与径流水质参数和气象参数的相关分析显示,所测各OCPs组分浓度与pH呈显著负相关,与径流的溶解性有机碳含量呈显著正相关,降雨量和雨前晴天数对不同组分OCPs的影响并不完全相同。平均贡献率的计算表明,雨水是城市地表径流中OCPs的一个重要来源,树冠水的贡献也不可忽视。

Contamination of organochlorine pesticides in rain, canopy throughfall and runoff water in Beijing urban area

This paper provided a comprehensive overview of the contamination of organochlorine pesticides(OCPs) in rain,canopy throughfall and runoff water in Beijing metropolitan area.Concentrations of hexachlorobenzene(HCB),hexachlorocyclohexanes(HCH) and dichlorodiphenyltrichloroethane(DDT) in rain,canopy throughfall water and runoff in urban area were presented.The result showed that HCH dominated in these samples(geometric mean 11.1,21.6 and 25.1 ng/L),followed by HCB(geometric mean 3.71,3.54 and 5.91 ng/L) and DDT(geometric mean 2.64,4.66 and 10.6 ng/L).In runoff samples,OCP concentrations were negatively correlated with pH value and positively correlated with dissolved organic carbon(DOC).The influencing parameters for different OCP species in runoff water varied.Rainfall accounted for a significant portion of OCPs in runoff,and the contribution of canopy throughfall water cannot be neglected.