Phosphorus Regeneration in the Ocean ? An Evaluation Using P and C NMR and Sequential Leaching of Marine Particulate Matter

ABSTRACT

OCE-0352756

An investigator from Stanford University proposes to utilize fresh suspended matter samples recovered from sediment traps in September 2003 at two sites in Monterey Bay (S2-300m and 1200m; S3-300m and 2400m) to study the composition of particulate organic carbon (POC) and particulate organic phosphorus (POP) using 13C and 31P-NMR (nuclear magnetic resonance) spectra. The investigator also plans to determine the P content in different operationally defined fractions (e.g., exchangeable P, Fe-bound P, apatite, carbonate bound P, detrital/inorganic P and organic P) of the suspended matter samples using SEDEX sequential leaching. The goals of the study are to evaluate the utility of NRM spectra to determine the composition of particulate organic matter (POM) in sediment traps, as well as investigate the seasonal and depth variability of the molecular composition of POM and P associations. Results from the project will be related to the availability and regeneration rates of P, as well as biological productivity and ecosystem structure in the water column.