Spatial Variability in CDOM Concentrations in Coastal Regions: Influences of Rainfall and Watershed Characteristics

Paula G Coble, USF, pcoble@marine.usf.edu (Presenting)
Barnali DIxon, USF, bdixon@stpt.usf.edu
Robyn N Conmy, USF, rconmy@marine.usf.edu

Understanding temporal trends in CDOM concentration and fluxes in rivers has become increasingly important due to the role of CDOM in water clarity, dissolved organic carbon flux, drinking water quality, and ecosystem health. Our recent work on the West Florida Shelf has shown that variability in river discharge is the major factor controlling CDOM concentrations on the shelf, with volume of freshwater discharge as a secondary factor. Numerous studies showing a link between soil organic matter content and DOC concentrations have led us to attempt a modeling approach to prediction of river CDOM discharge based on watershed characteristics such as land use and land cover, watershed hydrography, basin geography, flow paths, rainfall patterns, and soil composition, especially soil organic carbon and C:N ratios. We will present these results along with a preliminary model output selected basins in Southwest Florida.