This award will support collaborative research in biological oceanography between Dr. Francois Morel, Massachusetts Institute of Technology and Dr. Jean-Marie Martin, Ecole Normale Superieure, Paris, France. The objective of this project is to study the nature, dynamics, metal binding and geochemical role of colloids and microparticles in natural waters. The US and French groups have several common long term research aims: 1) to characterize aquatic particles (including colloids) and their dynamics 2) to characterize and model the binding of metals to particles and colloids and 3) to quantify; and model the role of solution/particle exchanges in the geochemistry and geobiology of trace elements in natural waters. In this project the collaborators will focus on 1) the development of fluorescence spectroscopy techniques for the characterization of aquatic particles and colloids and 2) the development of thermodynamic models of metal binding, validated and contrained with new specific calorimetric, kinetic and spectroscopic data. The project will benefit from the complementary expertise of the US investigator in large particles and geochemistry and the experience of the French in colloids and physicochemical mechanisms. Because microparticles and colloids have major carriers of trace elements in natural waters, an elucidation of their dynamics is essential to an understanding of the biogeochemistry of trace elements, both natural and anthropogenic.
