1. Manganese flux from continental margin sediments in a transect through the oxygen minimum
- Author
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Johnson, Kenneth S., Berelson, William M., Coale, Kenneth H., Coley, Teresa L., Elrod, Virginia A., Fairey, W. Russell, Iams, Helen D., Kilgore, Tammy E., and Nowicki, Jocelyn L.
- Subjects
Chemical oceanography -- Research -- Environmental aspects ,Manganese -- Environmental aspects -- Research ,Water chemistry -- Environmental aspects -- Research ,Sea-water -- Composition -- Environmental aspects -- Research ,Science and technology ,Composition ,Research ,Environmental aspects - Abstract
The flux of manganese from continental margin sediments to the ocean was measured with a free-vehicle, benthic flux chamber in a transect across the continental shelf and upper slope of the California margin. The highest fluxes were observed on the shallow continental shelf. Manganese flux decreased linearly with bottom water oxygen concentration, and the lowest fluxes occurred in the oxygen minimum zone (at a depth of 600 to 1000 meters). Although the flux of manganese from continental shelf sediments can account for the elevated concentrations observed in shallow, coastal waters, the flux from sediments that intersect the oxygen minimum cannot produce the subsurface concentration maximum of dissolved manganese that is observed in the Pacific Ocean., Manganese is widely used as a model element for studies of redox chemical cycles in the sea. Insoluble manganese oxides are readily reduced to soluble [Mn.sup.2+] by bacteria, photochemical reactions, [...]
- Published
- 1992