Examining the optical properties of colored dissolved organic matter (CDOM) in Puget Sound at Taylor dock using 3D excitation emission matrix spectroscopy

Colored dissolved organic matter (CDOM) is an active part of marine ecosystems which plays a key role in the carbon cycle. This study is going to evaluate the seasonal changes in CDOM over the course of a year in Taylor dock. CDOM is measured using 3D excitation emission matrix (EEM) spectroscopy which are visualized as contour plots. Three peaks have been identified which include humic-like (A & C), and protein-like (T) fluorescence. To further investigate the sources of the T peaks at Taylor Dock a six hour irradiation experiment was conducted using senescent seagrass, Zostera marina to see if the protein-like peaks were excreted from the seagrass during photodegradation or from anthropogenic sources such as oil based products. So far there have been no significant changes in the optical properties of CDOM for fall and winter but have potentially produced T peaks from irradiation. Before any conclusions can be made for this study we must account for spring and summer variation and further investigate the fluorescence of oil peaks in our samples