Sedimentation and Organic Carbon Burial in the Yangtze River and Hudson River Estuaries: Implications for the Global Carbon Budget

摘要

One of the most important challenges in global climate change research is balancing the carbon budget within the global carbon cycle. Carbon burial in sediments at the land–ocean interface has been difficult to quantify and model because it represents nonsteady- state boundary conditions that are also affected by human activities. In this study, we document carbon burial rates in the Yangtze River (1.6–4.9 × 10~(12) gC year~(-1)) and Hudson River (1.8–3.6 × 10~(10) gC year~(-1)) estuaries and integrate our results with carbon burial rates determined by others in the world’s 25 largest river-estuarine systems(6–11 × 10~(13) gC year~(-1)). Our results indicate that carbon burial in estuaries, bays, coves, lagoons, mud flats, marshes, mangroves, and other highly productive or protected lowenergy areas at the land–ocean interface along the entirety of the world’s coastlines may serve as an unrecognized sink within the global carbon budget.