| In winter, there exists a steady period of seasonal snow cover over five months, against which background, the characteristics of mercury exchange flux between snow and air on the surface of the earth. In 2011 Dec. and 2012 March, four sample sites categorized into two divisions were set in the flat field and slope field respectively. The mercury exchange flux was measured through dynamic flux chamber, DFC and LUMEX Zeeman RA915+ and other meteorology factors like solar irradiation, air temperature and air humidity were also determined chronologically. The characteristics of variation in mercury exchange flux between the snow and air and its relationship with the meteorology factors. The research results display that the mercury exchange flux distinctly shows the deposit process from the air to the snow-covered earth surface when there exists constant seasonal snow cover while it illustrates the alternative processes between the deposit and release under the marked melting trend, representing the reduction of one order magnitude in the total mercury flux level. In addition, the remarkable negative lineal correlativity can be seen between the mercury flux and air mercury concentration. However, the noticeable positive lineal correlativity has been found between the mercury flux and the solar irradiation whereas no distinct correlativity is shown between the mercury flux and the air temperature as well as the air humidity. |
