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Ombrotrophic peatlands are regarded as one of the faithful archives of atmospheric mercury(Hg)deposition,and a large number of studies on Hg accumulation in peatlands have been reported in Europe and North America.Comparatively little information is available about peat chronological records of atmospheric Hg flux in China.We investigated the concentration and historical accumulation rate of Hg(AR Hg)through geochemical analysis of three 210Pb-dated peat cores from Greater Hinggan Mountain,northeast China.Statistical analysis indicates no significant correlations between peat humification proxies and Hg accumulation,and the influence of organic matter decomposition on AR Hg is ignored in this study.The average Hg concentration(0.013±0.002 ?g g-1)and AR Hg(7.2±0.9 μg m-2 yr-1)in the peat layers pre-1830 are designated as the pre-industrial,background values.Pollution factors(PF Hg)suggest that the anthropogenic Hg flux has a gradually increasing trend,and four peaks are observed in 1900±20,1950±2,1980±10 and 2000±1,and are corresponding to the special social background periods.Some inter-core difference of AR Hg variation might be explained by the natural process of peat accumulation.The decreasing degree of recent Hg enrichment in the last two decades compared to the major peak is likely due to the increasingly intense environmental regulation and the gradual transformation of economic structure for sustainable development in China.