Allocation and adaptation in China’s blue carbon policy: a quantitative textual analysis based on a “theme-instrument-stage” framework

Blue carbon policy is a strategic priority for mitigating climate change and advancing marine conservation. Quantifying the attributes of these policies is essential for their scientific formulation and for driving sustainable innovation. Grounded in policy instrument theory, this study constructs a three-dimensional “Instrument-Theme-Stage” framework to evaluate the blue carbon policy documents issued in China since 2015. Through quantitative text analysis, the research examines the evolutionary process and distribution of policy instruments. Findings reveal that China has established a preliminary policy system which is heavily reliant on capacity-building instruments, whereas supply-oriented, regulatory, and demand-based instruments see limited use. Moreover, the analysis identifies structural imbalances, including disproportionate instrument allocation, uneven thematic coverage, and weak alignment between policy instruments and specific themes. To address these issues, this study recommends rebalancing the instrument mix, strengthening thematic coordination, and ensuring precise matching of instruments to policy goals. Doing so will improve the adaptability and strategic configuration of China’s blue carbon governance.