CARBON STOCKS AND EROSIONAL PROCESSES ON SELECT ISLANDS OF THE TIMUCUAN ECOLOGICAL PRESERVE IN NORTHERN FLORIDA

The Florida Department of Natural Resources designates “critical shoreline erosion” based partially on whether areas adjacent to the Atlantic Ocean or if areas have a value for recreation or development. Due to sea level rise and erosional forces, however, many inlets and estuaries in Florida are also being eroded and eaten away, altering carbon cycling, sedimentation rates, and the release of greenhouse gases into both the ocean and atmosphere. We are investigating Big and Little Talbot Island located in Duval County on the Atlantic Coast of Florida where we conduct research oriented around erosion, carbon stores, and carbon loss. These two islands are of special significance because due to a combination of development and sea level rise are eroding rapidly. High rates of erosion are occurring along the edges of Big Talbot Island (located in the Nassau Sound) and despite the rapid erosion rates and high concentrations of peat in the soils, they are not included as critical erosion shorelines. The soils here are typical spodosols with thick O horizons, often more than 7 cm thick. Vegetation transitions from old live oak hammock forests, to short palmetto dominated, to coastal dune pines and cedars as the elevation descends toward sea level. Our data collection so far indicates that even small islands such as this contain nearly 150,000 tons of below ground carbon and above ground carbon totaling near 100,000 tons. Shoreline erosion rates will be presented based on historical shore line locations.