| Mercury pollution issue has always been one of the research focuses in environmental science field since Minamata Disease event, which occurred in Japan in the early 1950s. In recent ten years, people have known that mercury can transport for very long distance by atmosphere circulation, so the stock of atmospheric mercury and its fluxes of import and export received special attention. According to the estimate, the global total amount of mercury imported into atmosphere was 6000 7500 t annually, and the natural sources accounting for 1/3, in which the soil was the main one. When mercury transported over some time and distances in the atmosphere, most (>90%) would come back to the terrestrial ecosystem and threaten the health of people through the food chain. There were lots of studies on the soil/air interface exchange abroad, but few at home.Based on above causes, the main cultivate soils (Purpli-Udic Cambosols) of Chongqing were regarded as objective of investigation in this study by field investigation combined with simulative experiment. The mercury exchange characteristic over soil/air interface of different purple soil (Dystric Purpli-Udic Cambosols, Typic Purpli-Udic Cambosols, Calcaric Purpli-Udic Cambosols) were studied by RA-915+ mercury analyzer and dynamic fluxes chamber technique on the spot. The influences of soil characters and weather conditions on mercury exchange fluxes were studied under the simulated nature condition in lab.The field study showed that mercury exchange fluxes of soil/air interface in different purple soils had some change. The average of mercury exchange fluxes increased with the increasing of soil pH. The results indicated that mercury fluxes of acid purple soil, neutral purple soil, calcareous purple soil and neutral purple soil polluted were 307.9±237.3 ng m-2 h-1, 349.0±258.6 ng m-2h-1, 390.1±270.2 ng m-2h-1, 906.8±775.8 ng m-2h-1, respectively. There were close relationships between... |
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