A new examination of trace metal-particle associations is proposed based on evidence supporting the hypothesis that dissolved barium gets its "nutrient like" distribution in the ocean, not through active uptake by phytoplankton during photosynthesis, but through barite precipitation in particulate microenvironment containing decaying organic matter and the remains of siliceous plankton. Diatom culturing (growth and death) experiments designed to test the hypothesis that barite precipitation dominantly occurs in particulate matter micro- environments will form the basis for this study. This study will contribute to the mechanistic framework needed for interpretation of existing trace metal profiles and provide additional rationale for future particulate and dissolved trace metal measurements in the worlds's oceans.
