| As a global pollutant, mercury posed serious impact on ecosystem because of its toxicity effects as well as obvious trend to bioaccumulation, biomagnification and methylation in organisms. Mercury pollution issue has always been one of the research focuses of environmental science field since Minamata Disease event, which was occurred in Japan during the early 1950s. People have realized many important aspects of mercury pollution such as its sources, transportation, transformation and harm. However, researches on quantitative relation between sources and sinks of mercury in environment have not been satisfactorily obtained because of total emission of mercury from anthropogenic sources were poorly listed in the world, and extensive measurement of mercury exchange flux over air-surface were not conducted. Right now, although total emission of mercury from anthropogenic sources have not been thoroughly researched in China. Moreover, concerning study reports of measurement of mercury release flux over air-surface are scarcerBase on above causes, Chongqing city was regarded as objective of investigation in this study, and combined methods of filed investigation and data collection were adopted to investigate in detail anthropogenic sources of mercury emission in Chongqing. A preliminary estimation on emission of mercury from anthropogenic sources in Chongqing apply to method of emission factors, its purpose is to provide detailed inventory of emission of mercury. At the same time, a Dynamic Flux Chamber (DFC) technique was applied to measure air-surface exchange flux of mercury over different field sites in these areas, and searching influence factors and characteristic of mercury release over environmental surfaces. The data of measurement in field sites were used to evaluate emission of mercury from natural sources in Chongqing.Results showed, mercury emission of main anthropogenic sources in Chongqing came from fuel combustion, coal combustion, cement manufacture, iron and steel production, chlor-alkali production, non-ferrous metal smelting, combustion of crop residue and wood, incineration of hazardous waste and medical waste, cremation, paint chemical industry, apparatus and instrument industry, fluorescent lamp, batteries disuse, thermometers production, using mercury for scientific research and dental amalgam etc.,A preliminary atmospheric emission of mercury from major anthropogenic sources in Chongqing were estimated through indirect approaches, based on annual process of total consumption or production for those sources, using acceptable emission factors, available data on mercury content in feedstock or product. In 2001, the emissions of total mercury to atmosphere from major anthropogenic sources in Chongqing were estimated to be approximately 8.85 tons andcorrespond to about 110 grams per square kilometer of emission strength of mercury. Among those sources, the coal combustion has been the largest source of anthropogenic emissions in this region contributing to about 57% to total emissions. Secondly, the cement manufacturing released approximately 1.51 tons to the atmosphere in 2001 contributing to about 17% total emissions, followed by paint production and using mercury industries (including research , dental amalgam, batteries, fluorescent lamp breakage, thermometers etc), wood and crop residue combustion, incineration and cremation, chlor-alkali production and metal manufacturing contributed to about 8%, 6%, 6%, 3% and 3% to total emissions, respectively, while fuel combustion contributed less than 1%.Air/surface exchange flux of mercury was investigated over six soil sites and four interfaces of watershed from different areas in Chongqing. Measurements of mercury fluxes were conducted by Dynamic Flux Chamber (DFC) in different seasons. The mercury fluxes over different sites and over different sites of same type have significant difference. In general, air-water interface exchange fluxes of mercury are higher than that of air-soil interface, the overall average value of mercu...
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