汞是唯一以气态单质形态随大气循环参与全球迁移的重金属元素,大气汞的长距离传输是汞的生物地球化学循环的重要特性之一,对全球汞循环有着重要的影响。由于汞的全球传输与沉降,汞在极地的污染不容忽视。科学工作者分别于1995年、2000年在北极和南极地区发现了大气汞亏损现象,并提出了对大气汞迁移转化的新认识,促进了对特殊气候、环境下汞在大气中的形态转化及其对陆地生态系统的影响研究。目前对极地大气汞亏损过程及其影响了解仍不够深入。本文从极地大气汞的分布、大气汞亏损的发生机制、沉降汞的归趋以及生物响应等综述了近年来对极地大气汞亏损的研究工作,并对极地大气汞亏损今后的研究方向作了展望,为特殊气候环境下大气汞的迁移转化机理研究提供借鉴。
Mercury(Hg) is the unique heavy metal transported with gaseous elemental Hg(GEM).Atmospheric Hg can be transported for a long distance,which plays an important role in global Hg cycle.Because of global transportation and deposition,Hg pollution in the polar regions has been concerned.Studies found atmospheric Hg depletion events(AMDEs) in Arctic and Antarctic in 1995 and 2000,respectively.This phenomenon presented a new cycling knowledge of atmospheric Hg in extreme climate and environment.However,current knowledge on atmospheric Hg chemistry and transporting process in polar regions is still unclear.In this paper,the authors presented atmospheric Hg distribution and AMDEs mechanisms,re-emission and impact on organisms in polar regions based on recent years work and proposed an overview on future research in the field.