Award: OCE-1154320

Dissolved organic matter is a reduced form of organic carbon that serves as a carbon and energy source for marine microorganisms. This research project sought to characterize the type of organic matter found in the deep sea, where three-quarters of marine dissolved organic matter is stored. The project advanced our understanding of organic compounds found in the deep sea by developing the use of novel analytical tools that provide structural information, a significant advance over the elemental formulas (how many carbon, hydrogen, nitrogen, oxygen, and other elements are found within each molecule) provided by existing methods. Our results reveal that these new tools are required in order to define spatial variability in dissolved organic matter in marine ecosystems. The elemental formula information is not sufficient to characterize the complex mixture of organic compounds found in seawater. Based on the structural information, some of the organic compounds are correlated to variability in cellular biomass. However, other compounds showed maximum values at deeper water depths within the water column. Thus, the composition of dissolved organic compounds is not simply a function of depth in the water column. Beyond the realm of research, the project also contributed to the broader community. The research team presented two classes for graduate students and postdocs on the use of ultrahigh resolution mass spectrometry in the analysis of dissolved organic matter. In addition, one-on-one assistance with data analysis helped make mass spectrometry data more accessible to students, postdocs, and scientists outside of Woods Hole Oceanographic Institution. The project also comprised a portion of the research conducted by a graduate student within the Kujawinski laboratory. The research cruise in 2013 also provided mentoring activities as 8 graduate students and 4 postdocs participated in the cruise, and 1st, 3rd, and 5th grade classrooms in Massachusetts were able to interact directly with scientists before the cruise and during live conversations in the middle of the cruise. Beyond the classroom setting, participants from the 2013 cruise and graduate students and postdocs in the Kujawinski laboratory participated in science fair activities in Woods Hole and New York City. Finally, a female graduate student was a major participant in this project and the research comprises half of her dissertation research. Last Modified: 04/27/2016 Submitted by: Elizabeth B Kujawinski