Research focuses on the carbon cycle in the Delaware Estuary (USA).  The objective is to examine the chemical composition of particles and dissolved organic matter in order to determine the origins (land plants, bacteria, or other organisms) and fates (bacterial consumption, metabolism, transformation of indigestable organic matter, export to the ocean, etc.) of these materials in the Delaware Bay.  Organic matter consists of carbon based materials such as proteins, carbohydrates, and fats which originate from living organisms.  Microcosm and mesocosm experiments were also conducted to examine the composition of particles and dissolved organic matter released by algae during growth and decay and was compared with field data.  Various biochemical components were measured including : bulk carbohydrates and molecular analyses of lipids, amino acids and lignin phenols using gas-chromatography-mass spectrometry.

  Dissolved organic matter is the largest reservoir of organic carbon in the ocean and is comparable to the amount of carbon dioxide in Earth's atmosphere.  Hence the cycling of dissolved organic matter is a key component of the global carbon cycle and perhaps global climate.  Unfortunately, much of the chemical composition of dissolved organic matter remains unknown.
    Current research involves elucidating the composition and sources of dissolved organic nitrogen and mechanisms which modify biochemicals to components which cannot be characterized by geochemical techniques.  Specific contributions of algae and bacteria are being examined using molecular approaches such as D/L amino acid ratios and lipid composition.

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