The seasonal evolution of the cadmium and lead distribution in the water column of the Gerlache Inlet (Ross Sea) was studied during the 1990#x2013;91 austral summer. Measurements were carried out by Anodic Stripping Voltammetry in Antarctica immediately after the collection and filtration of samples. The concentrations of both metals were homogeneous before the phytoplankton bloom with mean values of 0.71 (SD 0.10) and 0.116 (SD 0.014) nmol/1 for cadmium and lead respectively. A subsequent depletion in metal concentration was observed in the shallow waters. The surface concentration of cadmium decreased to about 0.1 nmol/1 at the end of the season. The vertical distribution of lead was less affected by the seasonal evolution and the mean surface concentration decreased to 0.044 nmol/1 in the same period. The results are evaluated with respect to physical and biological processes in the area examined and compared with those obtained on previous expeditions in the same area.
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