Ecomorphodynamic Feedbacks and Couplings Between Landscape Subsystems Influence Barrier Island Response to Changing Climate

Wednesday, 17 December 2014: 3:10 PM
Laura J. Moore1, John F Bruno2, Orencio Duran Vinent3, Sergio Fagherazzi4, Evan B Goldstein1, Theodore Lawrence Jass1, Rebecca Lauzon5, Giulio Mariotti6, A. Brad Murray5, David Walters1 and Donald R. Young7, (1)University of North Carolina at Chapel Hill, Geological Sciences, Chapel Hill, NC, United States, (2)University of North Carolina at Chapel Hill, Biology, Chapel Hill, NC, United States, (3)MARUM - University of Bremen, Bremen, Germany, (4)Boston University, Boston, MA, United States, (5)Duke University, Nicholas School of Environment, Durham, NC, United States, (6)Massachusetts Institute of Technology, Cambridge, MA, United States, (7)Virginia Commonwealth University, Biology, Richmond, VA, United States
Because barrier islands are low-lying and dynamic landforms, their habitats are especially sensitive to changing environmental conditions. The continued existence of barrier island landforms will depend on the degree to which islands can maintain elevation above sea level while also responding to changes in forcing by migrating landward. We are increasingly learning that ecomorphodynamic interactions (i.e., interactions between ecological and morphodynamic processes) as well as couplings between island and back-barrier marsh environments play a critical role in determining how barrier island systems will evolve as sea level rises, storm intensity increases and the species composition of coastal vegetation changes in the future. Here, we present an overview and synthesis of recent and new model experiments and observations that illustrate the importance of feedbacks between vegetative and sediment transport processes as well as the importance of ecomorphodynamic couplings between landscape units in influencing 1) the rate of formation, maximum height and morphology of coastal dunes; 2) overall island state (high vs. low) and the potential for rapid transitions in state to occur in response to gradually changing forcing; and 3) the persistence of back-barrier marshes, and thus the influence of back-barrier marshes on the rate of migration of barrier island-marsh systems.