Unlocking the climate and market potential of China's blue carbon ecosystems

To achieve its ambitious 2035 Nationally Determined Contributions (NDCs), including enhanced ecosystem carbon sinks, China needs to leverage nature-based solutions as part of its climate strategy. Blue carbon ecosystems represent vital yet underutilized solutions whose market viability remains poorly quantified at both national and provincial scales, limiting their integration into national policy and carbon market mechanisms. Here, we present an integrated ecological-economic assessment drawing on 932 data points to quantify the climate mitigation potential and investment viability of China's blue carbon ecosystems (mangroves, seagrasses, and saltmarshes). By combining CO₂e volumes derived from carbon stock estimates, with mean densities ranging from 54.59 (seagrass) to 214.27 (mangrove) MgC/hm² and financial modeling, we identify the carbon price thresholds required for project viability across different ecosystems and coastal provinces. Our analysis reveals a mitigation potential of 626,800 tCO₂e per year and a net present value of ∼92 million USD over a 30-year project horizon at a carbon price of 10 USD/tCO₂e. A carbon price sensitivity analysis identifies substantial variation in economic potential across ecosystem types and regions, highlighting the need for differentiated policy and financing mechanisms to realize blue carbon's full potential. These findings support informed decision-making for targeted policy reforms, investment mobilization, and market development, needed to unlock this vital sector for China's climate strategy. However, fully integrating nature on the balance sheet will require expanding assessments beyond the three core blue carbon ecosystems and including broader ecological services.