中文摘要：

以重庆市的主要耕作土壤——紫色土为研究对象,用动力通量箱与RA-915＋汞分析仪联用技术,通过室内模拟实验研究土壤湿度和浇水对紫色土土/气界面汞交换通量的影响.结果表明,加入外源硝酸汞的土壤汞交换通量大于加入硝酸亚汞的土壤汞交换通量,对照土壤的汞释放通量最小.随着土壤含水量的增加,土/气界面汞交换通量有增加的趋势,在土壤湿度接近土壤饱和含水量的60%时达到最大,但随着土壤湿度的继续增加,汞通量急剧下降.浇水对土/气界面汞交换通量也有较大的影响,当向土壤中均匀加水后,土壤中汞的释放量急剧下降,下降幅度达到42.4%—73.5%;水分在土壤中混合均匀后,土/气界面汞释放量又逐渐增加,约2—3 h后,汞释放通量才会达到或超过加水以前的水平.

英文摘要：

The predominant cultivated soils in Chongqing（Purpli-Udic Cambosols） were used as experimental materials to investigate the influences of soil moisture and watering on mercury exchange between air and soil surface.The mercury fluxes from soils were measured by dynamic chamber technique with a RA-915＋ mercury analyzer under differen soil moisture regimes.The mercury fluxes were higher in the soils amended with Hg（NO3）2 than in the soils amended with Hg2（NO3）2.The controls without receiving any exogenous mercury compounds showed the lowest mercury fluxes from soils.The fluxes of mercury from soil to the atmosphere increased with increasing soil moisture and reached the maximum when the soil moisture approximated 60% of saturation content.The mercury fluxes reduced rapidly to 42.4%—73.5% of the maximum during the initial period of water addition to soil.However,the mercury fluxes recovered to or even surpassed the previous levels 2—3 hours later,after water percolated and distributed uniformly in the soil.