ABSTRACT
There has been an increasing concern for the geochemical fate of trace metals in the marine environment. Many baseline studies have been made to determine the total concentration of these metals in the solution phase, the gas phase, and the solid phase (i.e., on and in living and nonliving material). Although these studies have been useful in indicating the fate of trace metals in the marine environment, little progress has been made in determining the mechanisms involved (physical, chemical, and biological) in the transfer of metals between phases. Part of the reason for this lack of understanding of trace metals in the marine environment comes from the difficulties in detecting experimentally the true activity (both thermodynamic and biochemical) of the trace metals; because of their low concentrations, conventional electrode methods of determining thermodynamic activity are difficult to apply. Although it is possible to detect the activity of some metals, we are at present forced to use models to estimate the thermodynamic activity of most trace metals to make comparisons with biological studies.
