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Requirements for modeling trace metal partitioning in oxidized estuarine sediments

Samuel N. Luoma·J.A. Davis
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Abstract

The fate of particulate-bound metals is of particular importance in estuaries because major biological energy flows involve consumption of detrital particles. The biological impact of particulate-bound metals is strongly influenced by the partitioning of metals among sediment components at the oxidized sediment-water interface. Adequate methods for directly measuring this partitioning are not available, thus a modeling approach may be most useful. Important requirements for such a model include: (1) determinations of metal binding intensities which are comparable among sediment components important in oxidized sediments; (2) comparable determinations of the binding capacities of the several forms of each component; (3) operational determinations of the abundance in natural sediments of components of defined binding capacity; (4) assessments of the influence of particle coatings and multicomponent aggregation on the available binding capacity of each substrate; (5) consideration of the effect of Ca and Mg competition on binding to different components; and (6) determinations of the kinetics of metal redistribution among components in oxidized sediments.

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Samuel N. Luoma, J.A. Davis. 1983. Requirements for modeling trace metal partitioning in oxidized estuarine sediments. https://doi.org/10.1016/0304-4203(83)90078-6

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