| Summary: | The Saguenay Fjord sediments are characterized by high trace metal, organic matter and iron monosulphide (AVS) concentrations. The presence of important maritime activities, as well as dredging operations and natural slumpling events, contribute to the resuspension of the Fjord sediments and changes in their redox conditions. === The objective of this research was to determine the impact of sediment resuspension on the remobilization of trace metals (e.g. Hg, Cu, Ni, Pb, As, Fe and Mn). in the water column. Once dissolved in the water column, the trace metals are subjected to a suite of geochemical processes, while remaining available for the uptake by the biota, until they find their way out of the fjord or back into the sediments. The results of the resuspension experiments conducted in the laboratory reflect the reactivity of these anoxic sediments as well as the trace metal desorption and readsorption kinetics. By monitoring the behaviour of different metals we were able to differentiate between the reactivity of those metals which are preferentially associated with the sulphides and organic matter. (Abstract shortened by UMI.)
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