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Concentrations and wet deposition fluxes of various mercury species in the atmosphere were estimated from April 2013 to March 2014 at Jinyun Mountain in Chongqing,China.Our results showed that the volume-weighted mean(VWM)and annual wet deposition fluxes of methyl mercury(MeHg)were 0.49ngL-1 and 0.65ugm-2yr-1,of total mercury(THg)were 32.25ngL-1 and 42.70ugm-2yr-1,of dissolved mercury(DHg)were 17.75ngL-1 and 23.50ugm-2yr-1,of particulate mercury(PHg)were 14.50ngL-1 and 19.20ugm-2yr-1,respectively.The proportion of MeHg in THg ranged from 0.1%to 7.7%with the mean value of 1.6%.The PHg fraction,which accounted for 3.2%~89.3%with an average of 48.3%of the THg,was lower than those reported in other previous studies,indicating that PHg was dominant among the different mercury species and the Jinyun Mountain has less anthropogenic pollution which can generate particles to the atmosphere.The results also showed a seasonal trend for mercury concentration and wet deposition flux.The highest concentrations of MeHg appeared in autumn.Whereas the highest concentrations of THg was measured in winter.As to wet deposition flux,the largest amounts of both MeHg and THg were observed in summer,while the minimum value of both occurring in winter.And a significant correlation between rainfall amounts and Hg wet deposition fluxes(r2=0.67,p<0.01 for MeHg; r2=0.62,p<0.01 for THg)suggesting that rainfall is one of the most important factors controlling the Hg fluxes.Moreover,this study implies that the combustion of fossil fuel,such as coal,and other human activities may affect the mercury levels in the precipitation.