Trace metals cycling, water column

Measurements of radionuclides and metals in marine sediments and particulate matter are conducted for a variety of purposes, including the determination of sedimentation rates, trace metal and radionuclide fluxes through the water column, enrichment of metals in specific phases of the sediments, and examination of new sedimentary phases produced after sediment deposition. Such studies address fundamental questions concerning the chronology of deep-sea and near-shore sedimentary deposits, removal mechanisms and cycling of metals in the ocean, and diagenesis within deep-sea sediments. 

To summarize, even though some Fe- and Mn-oxides may dissolve in the anoxic sediments of estuaries and thereby release trace metals, reoxidation of the Fe and Mn in the upper layers of the sediments, coagulation of Fe-Mn-humic-trace metal mixtures in the water column, and circulation patterns within the estuary all combine to return trace metals to the upstream particulate fraction. Turekian has suggested that while these processes allow significant internal cycling of trace metals in... 

Balistrieri, L. S., J. W. Murray, and B. Paul. 1992. The biogeochemical cycling of trace metals in the water column of Lake Sammamish, Washington response to seasonally anoxic conditions. Limnol. Oceanogr. 37 529-548. 

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