Zanardi, E. RSMAS/University of Miami, ezanardi@rsmas.miami.edu
Moore, C. RSMAS/University of Miami, cmoore@rsmas.miami.edu
Clark, C. RSMAS/University of Miami, cclark@rsmas.miami.edu
Zika, R. RSMAS/University of Miami, rzika@rsmas.miami.edu

 
FLUORESCENCE LIFETIMES OF SIZE-FRACTIONATED CDOM IN A SOUTH FLORIDA RIVERINE TO MARINE TRANSITION ZONE
 
Humic substances account for 40 to 60% of total dissolved organic material found in natural waters. They affect the optical quality of water and the speciation, transport, and fate of pollutants in natural waters and in water treatment processes. The optical characterization of these compounds as a function of their molecular weight distribution can yield information about their reactivity and mobility. Flow Field-Flow Fractionation (FFFF) separates DOM on size-fractionated basis and has many advantages over common CDOM separation techniques, but has never before been applied to marine CDOM. There have been limited fluorescence lifetime studies on humic substances, with only one on marine DOM. Fluorescence lifetimes can be more specific and sensitive to molecular structural changes than intensity measurements. Our new experimental approach couples FFFF as the separation technique with fluorescence characterization. To develop a better understanding of the differences/similarities between CDOM of marine and terrestrial origin and the impact these properties have on optical characteristics of coastal environments, we have examined a series of samples from a South Florida riverine to marine transition zone (Shark River/Florida Bay). Preliminary results indicate our experimental approach will be useful in examining the behavior of CDOM in freshwater and marine environments.
 
Day: Tuesday, Feb. 2
Time: Poster
Location: Sweeney Center
 
Code: SS34TU0490S