Trace Metal Cycling in the Water Column

Trace metals that are particle reactive (e.g., Pb) or have a nutrient-like behavior (e.g., Cd) are typically removed from surface waters via adsorption in their vertical transport through 

The importance of colloidal complexation clearly varies with the trace metal in question. For example, most of the Fe in rivers may be in colloidal form, which is critical in the coagulation/aggregation removal processes of Fe in estuaries (Millward and Turner, 1995). On the other hand, Cd and Ni have a low affinity for colloidal matter (Dai et al., 1995). In the Ochlocknee estuary (USA), Fe and Mn behaved nonconservatively and 

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