ABSTRACT

This chapter reviews blue carbon (C) accumulation by brackish and saline wetland-dominated estuaries from the perspective of estuarine net C balances. It examines the processes or C fluxes that are the basis of C accumulation and the mechanistic controls of those fluxes. Numerous C cycling processes contribute to the development of wetland-dominated estuaries and blue C accumulation in the coastal zone over time. Geomorphic studies show a coastal landscape comprised of wetland and open-water estuarine regions that change over time. Consider a coastal system comprised of tidal wetlands and adjacent aquatic estuarine waters and bottom sediments that is open to inputs from land and the ocean. Total suspended solids and organic C dynamics play a major role in the geomorphic development of wetlands and the relative area of wetlands and aquatic areas within the total system landscape. The chapter discusses how the long-term wetland development trajectories since the last glaciation will likely change direction in the near future.