COLLABORATIVE RESEARCH: IMPACT OF DOM SOURCE AND PHOTOOXIDATION ON CARBON CYCLING IN ESTUARIES

Old Dominion University Research Foundation, Norfolk VA

Investigators

Abstract

ABSTRACT OCE-0327423 OCE-0327446 Without understanding the type, magnitude and time scale over with dissolved organic matter (DOM) gets modified in rivers and estuaries, the regional and global delivery of total dissolved organic matter delivered to the ocean and its chemical and isotopic signatures will be poorly constrained. For this reason, scientists from the Virginia Institute of Marine Science and Old Dominion University plan to carry out a multi-technique approach to determine the photochemical and microbial processes that control the structural alteration and terminal oxidative losses of total dissolved organic matter (TDOM) during its residence in the York and Delaware River estuarine systems. These two temperate estuaries are characterized by different total dissolved organic matter ages and sources. Utilizing photochemical (i.e., irradiation), stable and radio-isotopic, structural tools (i.e., 13C-NMR) and bacterial degradation experiments, the PIs will evaluate how the photochemical and microbial processes mechanistically impact the qualitative and quantitative nature of TDOM export and how photochemical reactivity of estuarine DOM is changed by riverine source age, composition and photo-oxidation/photobleaching.