西藏错鄂湖和羊卓雍湖水体及沉积物中有机氯农药的初步研究

对2002年5月采集的西藏错鄂湖和羊卓雍湖的水和沉积物样品进行了实验及分析。结果表明，这2个高原湖泊均不同程度地受到有机氯农药的污染，并具有多种有机氯农药的同时存在、在沉积柱上近表层没有含量下降趋势以及南部的羊卓雍湖污染程度高于藏北的错鄂湖等特点，反映出湖泊中的有机氯农药有可能是随孟加拉湾洋暖流由南向北带人的。两个湖泊的水与沉积物中滴滴涕(DDTs)和六六六(HCHs)含量甚至与我国东部地区的一些淡水水体相近，这种现象很可能表明，大气沉降的有机氯农药可在青藏高原湖泊水体与沉积物中发生一定程度的累积。长远地看，这一过程将可能对青藏高原野生动物产生负面影响。

A preliminary study of organochlorine pesticides in water and sediments from two Tibetan lakes

Organochlorine pesticides (OCPs) in water and sediments from two Tibetan lakes, Lake Yamzho Yumco and Lake Co Ngoin, are analyzed by GC ECD. The results show that the two pristine Tibetan lakes are significantly contaminated by OCPs. The occurrence of a variety of OCPs, the absence of an up profile decreasing trend around the surface layer, as well as the higher concentrations of OCPs in Lake Yamzho Yumco compared to the northern Lake Co Ngoin may probably suggest a significant long range atmospheric transport (LRAT) of OCPs by air flows from Bay of Bengal to Tibet. It should be noted that the DDTs and HCHs concentrations in water and sediments from the two Tibetan lakes were even within the range of those in eastern China regions, indicating an accumulation of OCPs in Tibetan lacustrine environment, which may exert a long term negative impact on the wildlife in Tibet.