Preliminary study of carbon and water vapor fluxes above a coastal salt marsh ecosystem

Salt marshes play an important role in global carbon cycle. These ecosystems are generally characterized by high productivity. However, the understanding of marsh-atmosphere exchange is modest at best. This is especially true when compared to other terrestrial ecosystems. This paper reports on a first such study where fluxes were measured using an eddy-covariance tower located in a Spartina marsh near Sapelo island on the southeast coast. Data are presented to examine both the strength of the carbon sink and the related vertical fluxes of Spartina. The influence of tide cycle and footprint on the Spartina-atmosphere exchanges of carbon, water vapor and energy are integrated into the assessment of the carbon sink.