Ingall 9730159 The importance of dissolved organic matter (DOM) in marine organic carbon cycling is now widely recognized. The essential nutrient phosphorus in DOM is potentially a significant source of P for algal and microbial metabolism, however little is known about the chemical composition and cycling of dissolved organic phosphorus (DOP). The PI, Ingall, proposes to study the chemical composition and structure of DOP and particulate OP in the coastal and open oceans. Efforts will be focused on that fraction of the DOP pool that is isolated with a tangential-flow ultrafilter, and hence is expected to represent the colloidal or high molecular weight fraction of DOP. Samples will be obtained from previously collected and newly collected field samples, as well as from controlled laboratory culturing and decomposition experiments. These samples will be analyzed using newly developed 31P NMR techniques. The results of this study are expected to lead to the quantification and identification of organic P compounds, and are thus an important step in gaining a more complete understanding of P cycling in the oceans. Ingall (OCE-9730159)
