The Concentration,Species And Influnencing Factors Of Atmospheric Mercury In The Urban And Remote Areas

The source, temporal and influencing factor of atmospheric mercury is one of the research focuses on atmospheric chemistry and aerosols. In order to better understand the background concentration of atmospheric mercury, the spatial and temporal distribution characteristics of atmospheric transformation mechanism, characteristics and long-distance transmission of the sources and sinks, atmospheric mercury in large and medium-sized cities and the Arctic were selected to monitor and comparative study.The main conclusions are as follows:(1) Atmospheric mercury in Hefei.TGM concentration in Hefei was2.53±1.36ng/m3and range was0.40-12.34ng/m3in the period January2009to June. The TGM concentration reaches its maximum in the morning07:00-09:00and minimize during14:00-16:00.The average concentration of atmospheric particulate total mercury (TPM) in Hefei was310pg/m3and ranged from160pg/m3to580pg/m3(January2009to June).The average concentration of inhalable particulate mercury (Hg-PM10and Hg-PM2.5) were350pg/m3and280pg/m3(April2008-2009May),the concentration of Hg-PM2.5accounting for80%of the concentration of Hg-PM10, this means that particulate mercury tend to be attached to the fine particles. In the sampling period, the largest contribution to particulate mercury is coal, followed by biomass burning, vehicle exhaust is the lowest. The correlation between TPM and TGM showed a positive from January to mid-March and a negative from mid-March to mid-May.(2) Atmospheric mercury in the Pearl River Delta. The TGM concentration in the town of Wanqingsha was2.94±2.02ng/m3and ranged from0.50to18.67ng/m3(November23,2008to December22). The TGM concentration reaches its maximum in the morning07:00-08:00and down to its minimum in the afternoon14:00-16:00. The average concentration in the night (18:00-6:00) was3.12ng/m3and the average concentration in the daytime (6:00-18:00) was2.74ng/m3.42.55%of the high concentrations (>8ng/m3) was come from Dongguan direction and57.45%from the direction of Shenzhen and Hong Kong. The TGM and temperature showing a significant negative correlation (R2=0.8458). The TGM and ozone also showing a significant negative correlation (p<0.01, r=-0.864)(3) Atmospheric mercury in Xiamen. The TGM average concentration in Xiamen was3.34±1.94ng/m3and ranged from0.29to14.99ng/m3(March23,2011to June7). The TGM concentration reached the maximum value in the morning06:00-07:00and the minimum value in the afternoon17:00. The TGM average concentration in night (18:00-06:00) was3.39ng/m3and in daytime (06:00-18:00) was3.17ng/m3, the former than the latter7%. In the sampling period, the high TGM concentrations were mostly from local source and few from the long-distance transmission source. In the sampling period (March21,2011to2011), the average concentration of GEM. RGM and Hgp were3.05±1.08ng/m3,20.63±8.14pg/m3and36.58±14.78pg/m3. GEM accounted for97.98%of the total atmospheric mercury, the RGM accounted for0.845%of the total atmospheric mercury, Hgp accounted for1.175%of the total atmospheric mercury. Correlation coefficient of GEM-Hgp, GEM-RGM and RGM-Hgp all showed a positive correlation. The R2(GEM-Hgp)=0.3311, the R2(GEM-RGM), R2(RGM-Hgp R2=0.5513.(4) Atmosphere mecury in Fourth National Arctic Research Expedition. The TGM average concentration in the entire route (July1,2010to September20) was1.99±0.89ng/m3and ranged from0.42to8.97ng/m3. The TGM concentrations in Sea of Japan during the round-trip voyage were0.89±0.16ng/m3and3.41±1.78ng/m3respectively; The TGM concentrations in Sea of Okhotsk during the round-trip voyage were0.76±0.15ng/m3and2.68±0.78ng/m3respectively; The TGM concentrations in Bering Sea during the round-trip voyage were1.21±0.36ng/m3and2.62±0.38ng/m3respectively.The TGM concentration in open waters of the Arctic Circle (N°66-N°75) was1.85±0.53ng/m3. The TGM concentration in ice floes district (N°75-N°85) was2.12±0.54ng/m3. The TGM concentration in permanent ice(N°85-N°90) was2.03±0.52ng/m3. Sea of Japan and Okhotsk may be sinks of the TGM.The TGM concentration values in ice floes distrct was higher than these in permanent ice and open waters,which means that the sea ice melting might be an important reason of the high value of the TGM concentration.