Climate change is driving a fundamental reorganization of the coastal zone, in which carbon-rich ecosystems are simultaneously migrating, accreting and submerging. In this Review, we discuss the geomorphic processes constraining soil carbon accumulation and the ecological processes constraining greenhouse gas emissions that together determine the net radiative forcing of the coastal landscape and the size of the coastal carbon sink. Sea level rise creates vertical and lateral accommodation space that potentially enhances soil carbon accumulation in marshes and mangroves. However, sea level rise and saltwater intrusion lead to ecosystem transitions that result in loss of existing carbon pools, altering the balance between carbon sequestration and greenhouse gas emissions. We propose that ecosystem reorganization results in large, but mostly offsetting, changes in radiative forcing. At the continental scale, losses in soil carbon sequestration and wood production are offset by reduced methane emissions associated with salinization of freshwater ecosystems. Nevertheless, climate effects on the coastal carbon sink remain largely studied within individual ecosystems. Future work is needed to determine the connectivity of carbon between ecosystems, changes in carbon accumulation and greenhouse gas emissions as ecosystem transitions occur, and the fate of carbon as it moves through the coastal landscape.

气候变化正在推动沿海地区的根本重组，其中富含碳的生态系统正在同时迁移、增生和淹没。在这篇综述中，我们讨论了限制土壤碳积累的地貌过程和限制温室气体排放的生态过程，它们共同决定了沿海景观的净辐射强迫和沿海碳汇的规模。海平面上升创造了垂直和横向的适应空间，有可能增加沼泽和红树林中土壤碳的积累。然而，海平面上升和海水入侵导致生态系统转变，导致现有碳库的损失，改变碳封存和温室气体排放之间的平衡。我们建议生态系统重组会导致大量的，但主要是抵消辐射强迫的变化。在大陆范围内，与淡水生态系统盐化相关的甲烷排放量减少抵消了土壤固碳和木材生产的损失。尽管如此，气候对沿海碳汇的影响仍主要在单个生态系统内进行研究。未来的工作需要确定生态系统之间碳的连通性、生态系统转变时碳积累和温室气体排放的变化，以及碳在沿海景观中移动时的命运。气候对沿海碳汇的影响主要在个别生态系统内进行研究。未来的工作需要确定生态系统之间碳的连通性、生态系统转变时碳积累和温室气体排放的变化，以及碳在沿海景观中移动时的命运。气候对沿海碳汇的影响主要在个别生态系统内进行研究。未来的工作需要确定生态系统之间碳的连通性、生态系统转变时碳积累和温室气体排放的变化，以及碳在沿海景观中移动时的命运。