Mobilidade do mercúrio no Pantanal de Poconé

Abstract

Along the Tanque dos Padres stream, the drainage is afected by gold prospecting. Biogeochemical variables were monitored as a function of seasonality. We also performed essays simulating extreme pollution situations regarding both biota and active stream sediments. Pluviometric indexes indicate two clear-cut "seasons", rainy (december to may) and dry Uune to november). Eh and pH values during the rainy period are dose to the Jimits that favor the oxidized states of mercury and are also conditions required for metylation processes. KRAUSKOPF's (1956) studies, indicating that cations including mercury are strongly adsorbed by iron oxides are confirmed. Biota analyses confirm that regional sediment constituints perform the natural control of mercury.