The marine industry plays a crucial role in the survival and well-being of hundreds of millions of coastal residents. However, current methods for accounting in the blue economy face significant challenges, primarily due to the lack of appropriate measurement indicators to assess the vulnerability of the marine industry chain. We introduce a Multi-Regional Input-Output Model tailored to capture the marine industry within China's coastal provinces, propose a provincial-domestic-international multi-cycle decomposition framework, and define the production dependence degree to measure industrial chain vulnerability. This approach overcomes the limitations of traditional economic dependence measures, which often suffer from mismatches between numerator and denominator, and addresses the inadequacies of sector-level production vulnerability assessments. We evaluate forward and backward production dependencies at both the regional and marine industry levels across 97 countries and regions for 2017, exploring regional heterogeneity, marine industry differentiation, and assessing the vulnerability of China's marine industry chain, which leads to the formulation of policy recommendations.

Production Dependence,Marine Industry,Multi-Regional Input-Output Mode