Radioactivity in the Marine Environment (1971) / Chapter Skim
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MARINE CHEMISTRY
MARINE CHEMISTRY
Pages 137-146
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From page 137... ...
The total ocean-wide productions can be estimated from the deep-water excesses (concentration in deep water minus concentration in surface water) of silicate, of total dissolved inorganic carbon or carbonate alkalinity, or of nitrate and phosphate.
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From page 138... ...
The carbonate alkalinity, nitrogen, phosphorus, and carbon data are internally consistent, and show that for each mole of CaCO3 dissolving in the deep sea, organic material containing 3 moles of organic carbon must be oxidized. The silicon data Concentration Factors (liters seawater per Plankton Ash (Mg/g)
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From page 139... ...
Elements have also been classified according to their residence time and reactivity in seawater. The coastal ocean is characterized by rapid mixing of substances, partial retention close to coast of solids and certain reactive elements, relatively intense biological activity, and abundance of particles.
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From page 140... ...
1965. Chemical oceanography.
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From page 141... ...
Marine sediments deposited at great depths and far from waste-disposal localities contain little fallout and waste activity. The explanation is that a soluble radionuclide introduced into the sea will have a fate similar to that of the natural elements (see Chapter 5)
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From page 142... ...
Radionuclide Sequence Some radionuclides are more strongly sorbed to sediment particles than others; the specific sequence varies with different sediments. In some Atlantic, Pacific, and Indian Ocean and Mediterranean Sea sediments, the sequence of sorption of radionuclides from seawater (from those weakly sorbed to those strongly sorbed)
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From page 143... ...
' i in. Irish Sea sediments were exposed in the field to radionuclides discharged near Sellafield (Jones, 1960)
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From page 144... ...
. The cation exchange capacity is calculated as follows (Duursma and Eisma, unpublished)
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From page 145... ...
12345 0 1 2 3 4 5 IRON (%) FIGUKE 4 Distribution coefficients (K)
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From page 146... ...
Consequently, we must consider radionuclide behavior under anoxic conditions. Experiments using Black Sea sediment under oxidizing and reducing conditions show that there is little change in the distribution coefficients of many radionuclides (Table 2)
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