Based on Geodetector and GTWR models: Quantitative attribution of spatial distribution of marine fishery carbon sink resources in China

The spatial distribution of marine fishery carbon sinks is critical for evaluating regional ecological value and optimizing resource allocation. This study focuses on marine fishery carbon sinks in China nine coastal provinces (2004-2023). It first analyzes their spatiotemporal dynamics, then uses an integrated Geodetector-GTWR framework to quantify 20 influencing factors and their impact magnitudes. Results show: (1) Total supply capacity of marine fishery carbon sinks increased overall, with marked spatial disparities, presenting an “high at both ends, low in the middle” and interspersed high-low distribution. Resource agglomeration zones shifted from northeast to southwest, forming a “north-higher-than-south” pattern and migrating toward offshore deep waters. (2) The spatial distribution is driven by interactions of 20 spatially heterogeneous factors (e.g., resident urbanization rate, total social fixed-asset investment, marine resources, and marine pollution). (3) Synergistic effects of 20 statistically significant factors (not individual factors) dominate the distribution pattern and drive supply capacity. Aquaculture pesticide intensity shows the most significant spatial heterogeneity; marine fishery carbon sink area exerts consistent positive effects across provinces. Notably, labor force size strengthens interactions with other factors most prominently, making it key for optimizing resource allocation. This study provides a scientific basis for region-specific management of marine fishery carbon sinks and supports China dual carbon goals. • To quantify spatiotemporal patterns & driving mechanisms of marine fishery carbon sinks in China's 9 coastal provinces, informing ecological optimization. • Integrate Geodetector-GTWR to analyze 20 influencing factors across 6 dimensions (social, economic, geographic, etc.). • Spatial distribution shows “high at both ends, low in the middle”; factor synergy (not individual effects) dominates, with labor force key. • First to use Geodetector-GTWR integration for spatiotemporal attribution of marine fishery carbon sinks, revealing overlooked interactions. • Inform region-specific policies & blue carbon governance to support China's “dual carbon” goals and sustainable resource management.