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Taiwan is located downwind of the East Asian continent,which is the largest anthropogenic mercury(Hg)source region globally.Continuous measurements of speciated atmospheric Hg have been conducted at the Lulin Atmospheric Background Station(LABS; 120.87?E,23.47?N,2862 m a.s.l.)in central Taiwan since April 2006 to study the export of the East Asian Hg emissions.Between April 2006 and November 2013,the mean concentrations of gaseous elemental Hg(GEM),reactive gaseous Hg(RGM),and particulate mercury(PHg)were 1.6 ng m^-3,18.2 pg m^-3,and 2.6 pg m^-3,respectively.A diurnal pattern was observed for GEM with afternoon peaks and nighttime lows,whereas the diurnal pattern of RGM was opposite to that of GEM.Concentration-weighted trajectory(CWT)approach was applied to identify potential source regions of speciated atmospheric Hg.Southwest China and northern Indochina Peninsula were major source regions of GEM,RGM and PHg.There was an additional source region for GEM extending from northeast China along the coastal region of east China.Moreover,air from South China Sea and the Pacific Ocean could also be enriched with RGM,suggesting sources other than anthropogenic emissions.Using the data of 2010,dry deposition fluxes of GEM,RGM,and PHg were estimated to be 58.8,10.6,and 0.1 μg m^-2,respectively,with a total dry flux of 69.5 μg m^-2.On the other hand,the annual wet Hg deposition flux was 33.7 μg m^-2.Although the dry flux was more important,wet flux dominated in summer month because of abundant rainfall.