“Blue carbon,” or organic carbon (OC) derived from and stored in coastal and marine environments, is recognized as an important OC sink within the global carbon cycle, particularly in mangrove, salt marsh, and seagrass settings. However, as sea level continues to rise, these blue carbon reserves will become increasingly sensitive to wetland erosion/loss, particularly in low relief coastlines such as the Florida coast where blue carbon is abundant. Although blue carbon can be stored in sediments for hundreds to thousands of years with little alteration, it is unclear how its reactivity will respond to remobilization into the marine environment. For example, in controlled laboratory experiments, the presence of highly reactive substrates (e.g. simple sugars and algal leachates) has been shown to cause the breakdown of terrestrially-derived dissolved organic carbon (TDOC) to occur ~4 times faster over a several week period and up to 75 times faster during the first 24 hours. This phenomenon is known as the “priming effect,” and although it has been well-studied in soils, priming has been largely ignored by aquatic and marine communities until recently.
Proposer: Thomas Bianchi, University of Florida