Hg 污染具有全球性，人类活动较少地区的湖泊沉积物对长距离输入的大气沉降 Hg 变化敏感。巴丹吉林沙漠中发育了约142个沙漠丘间湖泊，是研究大气沉降 Hg 记录的理想材料。选择巴丹吉林沙漠东南部的宝日陶勒盖湖泊进行湖泊钻探，结合210 Pbuns和137 Cs 核素测年及 THg 沉积通量计算，重建了400年来巴丹吉林沙漠湖泊的 THg 沉积记录，并探讨了影响沙漠湖泊 THg 沉积的影响因素，评估了自然背景和人类活动的影响。结果表明：（1）沉积物中 THg 含量分布范围为1.5～17.5 ng／g，富集系数和沉积通量的分布范围分别为0.3～4.5和2.9～38.9μg／（cm2·a）。THg 含量、富集系数和沉积通量均表现为在岩心上部近几十年富集。（2）近400年来，湖泊沉积物中背景 THg（THg岩石风化）通量变化相对稳定，主要受控于附近物源供给和区域风沙活动。大气沉降 THg（THg大气）通量自20世纪30年代以来呈逐渐增加的趋势，很大程度上反映了近几十年来人为源大气沉降 THg 的增加。但20世纪30年代以来岩心局部的大气沉降 THg 通量的峰值可能还受全球变暖和湖泊生产力增加的影响，而20世纪30年代之前出现的峰值可能与“小冰期”冷期强烈的区域风沙活动有关。巴丹吉林沙漠湖泊400年来的 THg大气沉积通量变化与全球 Hg 产量和冰心中的大气 Hg 含量变化记录一致，是沙漠地区大气沉降 THg 的可信纪录。%The Hg pollution is a global problem.The lacustrine sediment in remote area is sensitive to atmos-pheric Hg deposition by long-distance transportation and they are ideal materials for studying atmospheric Hg cy-cling.The Badain Jaran Desert is located in the Northwest China where there are about 142 permanent inter-dune lakes,and lacustrine sediments from these lakes are ideal materials for study atmospheric Hg deposition in remote desert region due to less human activities.The inter-dune lake,the Baoritaolegai,in the southeast of the Badain Jaran Desert,was selected for this study.The sediment core (BR-2)was dated by 210 Pbuns and 137 Cs. Results derived from the sediment core BR-1 suggest that:(1)THg concentration ranges from 1.5 to 17.5 ng/g, the flux ranges from 2.9 to 38.9 μg/(cm2·a)and EF ranges from 0.3 to 4.5,respectively,and the THg con-tent enriched in the recent decades;(2 )The flux of THg in the Core BR-1 is composed of background (THglithogenic )and atmospheric fractions (THgatmospheric ).The flux variety of the THglithogenic fraction during 400 years is relative stable which are controlled mainly by nearby material source supply and regional aeolian activi-ties.Gradually increasing flux of the THgatmospheric fraction since 1930s,to a great extent,indicates the growth of anthropocentric THg in the recent decades.To the low background THg in the Badain Jaran Desert lake and the natural fluctuation affected by climate or the environmental change of the lacustrine sediment are considered. Peaks of the THgatmospheric flux occurring in the Core BR-1 after 1930s may be relating with global warming and in-creasing lake productivity while THgatmospheric flux changes may link with the nearby material source and aeolian activities before 1930s.Signals revealed by the 400 years'THgatmospheric flux from the inter-dune lacustrine sedi-ment in the Badain Jaran Desert is consisting with global Hg production and a THg record from ice core from North American,which can be regarded as a reliable record of the desert region atmospheric THg.
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