中文摘要：

为了弄清楚普定水库汞的地球化学循环特征，用金汞齐-冷原子荧光光谱法（CVAFS）和气相色谱技术（GC），研究了乌江流域上游普定水库水体剖面和沉积物间隙水剖面汞的赋存形态（总汞THg）、溶解态汞（DHg）、活性汞（RHg）、颗粒态汞（PHg）、总甲基汞（TMeHg）、溶解态甲基汞（DMeHg）和颗粒态甲基汞（PMeHg）的分布特征。结果显示，普定水库水体总汞浓度为1．29～3．18ng／L，活性汞浓度为0．09～O．43ng／L，总甲基汞浓度为0．06～0．18ng／L。沉积物间隙水中溶解态汞浓度为2．65～11．47ng／L，溶解态甲基汞浓度为0．06～1．16ng／L。实验数据表明，普定水库水体中溶解态汞和颗粒态含量相当，其中颗粒态汞占总汞的比例为46％，并与总汞存在极显著相关性（R=0．929，n=20，P〈0．01），溶解态汞与总汞相关性不明显（R=-0．067，n=20）；冬季普定水库甲基汞以溶解态甲基汞为主，溶解态甲基汞占总甲基汞的比例为63％，溶解态甲基汞与总甲基汞无明显相关关系（R=0．292，n=20），颗粒态甲基汞与总甲基汞存在极显著的相关性（R=0．815，n=20，P〈0．01）。试验数据表明沉积物孔隙水溶解态汞与溶解态甲基汞浓度明显高于上覆水体，是普定水库水体中汞的一个重要来源。

英文摘要：

In order to study geochemistry circle of mercury in Puding Reservoir, the concentrations and distrtbutions of various mercury （Hg） species, including total Hg （THg）, dissolved Hg （DHg）, reactive Hg （RHg）, particulate Hg （PHg）, total methylmercury （TMeHg）, dissolved methylmercury （DMeHg）, and particulate methylmercury（PMeHg） in the columns of water body and sediment porewater of Puding Reservoir, were determined by distillation-ethylation（GC-CVAFS） technique. The concentrations of THg, RHg, and TMeHg in the water columns ranged from 1.29 to 3.18 ng/L, from 0.09 to 0.43 ng/L, and from 0.06 to 0.18 ng/L, respectively. The concentrations of DHg and DMeHg in the porewater of sediment ranged from 2.65 to 11.47 ng/L and from 0.06 to 1.16 ng/L, respectively. Particulate Hg, which accounted for 46% of THg, was significantly correlated with THg; PMeHg, which accounted for 37 % of TMeHg, was positively correlated to TMeHg; and the distributions of MeHgT were controlled by DMeHg. Moreover, the concentrations of DHg and DMeHg in porewater were higher than those in the water at interface, which suggested that sediment was the dominant Hg source to the reservoir.