摘要
本文估计了莫日-瓜苏河水和悬浮泥沙样中和位于主河道采样点下游的其三个沿海泻湖(卡廷圭卢、巴里尼亚以及里奥佩德拉斯)的水体和河底泥沙中的总汞含量。结果发现,悬浮泥沙和河底泥沙中的汞浓度均较低。铝被用来作为校正里奥佩德拉斯泻湖沉积岩心中汞浓度的地球化学示踪物(r=0.92)。据估计,莫日-瓜苏河每年输送19kg汞,其中65%处于溶解状态,35%吸附在颗粒性物质上。在1970～1980年期间观察到的急性中毒时期之后,河流流域主要通过自然恢复和进入生态系的汞输入量普通降低,已恢复到其原来的状态。
Total mercury content was evaluated in water and suspended sediment samples of the Moji-Guau river and in water and bottom sediment of its 3 marginal lagoons (Catingueiro, Barrinha, and Rio das Pedras), located down-stream of the sampling point in the main channel. In all situations, low Hg concentrations were found in suspended and bottom sediments. Aluminum was used as a geo-chemical tracer to normalize the Hg concentrations in the sediment cores from the Rio das Pedras lagoon (r = 0.92). It was estimated that the Moji-Guacu river transports up to 19 kg Hg yr^-1, 65% in the dissolved form and 35% adsorbed onto particulate matter. Following an acute toxic stage observed in the years 1970–1980, the basin has been restored to its original conditions mainly by natural recovery and a general reduction in Hg input to the eco-system.
