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Mercury,especially methyl mercury,is a highly toxic metal that can pose adverse effects on human health normally by consuming fish.There are three major forms in the atmosphere named gaseous elemental mercury(GEM),gaseous oxidized mercury(GOM),and particulate bounded mercury(PBM).The GEM,which is fairly stable and normally has a residence time of 0.5 – 1.0 yr in the atmosphere,plays an important role in the biogeochemical cycle of Hg in the global scale.On the other hand,GOM and PBM are primary pathways of Hg scavenging from the atmosphere and entering remote aquatic environments where methyl mercury production happens.From July 2013,we conducted continuous measurements of speciated atmospheric Hg at a rural site in Mt.Changbai forest area,northeast China.The averaged concentrations of GEM,GOM,and PBM were 1.73 ± 0.48 ng m-3,5.7 ± 6.8 pg m-3,and 18.9 ± 15.6 pg m-3,repetitively.In general,the levels of atmospheric Hg species were relatively lower compared to those obtained from other rural sites in China but in a good agreement with the mean levels in North America and Europe.All the speciation of atmospheric mercury showed a typical seasonal diurnal pattern during the study period,with elevated concentrations observed in cold seasons.Significant positive linear correlations were observed between GEM and PBM in cold seasons,whereas no significant linear correlations were observed between GEM and BPM in warm seasons.This indicates GEM and PBM were impacted by similar anthropogenic sources in cold seasons.