Assessing Loss of "Blue Carbon" from Coastal Ecosystems due to Eutrophication and Other Anthropogenic Factors

Heidi Dierssen, University of Connecticut, heidi.dierssen@uconn.edu (Presenter)

"Blue carbon" is the term used to describe the long-term carbon (C) stored for hundreds to thousands of years in the biomass and deep sediments of vegetated ecosystems such as tidal marshes, mangroves, and seagrass beds. Coastal ecosystems are disappearing at alarming rates, but quantification of the global area of these ecosystems, loss rates, and the subsequent release and fate of blue carbon is lacking. Sensitivity studies suggest that up to 1 billion tons of "blue" carbon dioxide are released each year with an estimated economic cost reaching $40 billion annually. Here, I will address some of the methods for quantifying the spatial extent of these valuable coastal ecosystems using earth observation tools. A case study will also be presented on ocean color remote sensing of seagrass habitats from satellite or airborne sensor. Reflectance of a seagrass meadow is the result of complex interactions between the overlying water column, the canopy bi-directional reflectance distribution function (BRDF) resulting from canopy structure and position, and leaf and sediment optical properties. Results from a 3-dimensonal radiative transfer model and an application using hyperspectral airborne PRISM imagery will be presented. In addition, the potential for remote sensing of carbon exported as leaf debris or "wrack" from seagrass meadows will be considered. More robust methods for mapping the distribution of these valuable ecosystems will allow for better estimates of habitat loss and carbon exchange between the oceanic, terrestrial, and atmospheric reservoirs.

Presentation Type:  Plenary Talk

Session:  Theme 4: Human influence on global ecosystems

Presentation Time:  Wed 10:30 AM  (18 minutes)