Research on the impact of marine financial support on economic resilience and sustainable development in coastal areas

Marine financial support, as an important means of optimizing resource allocation and risk protection in coastal areas, provides key support for enhancing economic resilience and achieving sustainable development. This paper constructs the Marine financial support index based on panel data of 11 coastal provinces in China from 2011 to 2023, and uses fixed effects, instrumental variables and threshold models to systematically evaluate its economic and ecological effects. The study found that Marine financial support significantly enhanced the economic resilience and sustainable development level of coastal regions, and its promoting effect was achieved through the optimization of capital factor allocation and the improvement of green innovation capacity, and showed obvious nonlinear threshold characteristics. Heterogeneity analysis shows that after the release of the maritime power strategy, the function of Marine finance has shifted from scale expansion to quality improvement, and its role is more prominent in regions with a better economic foundation, moderate environmental regulations and southern coastal areas. This paper provides empirical evidence and policy references for optimizing the allocation of Marine financial resources and enhancing the resilience and green transformation capacity of coastal systems. • Blue finance significantly strengthens resilience in coastal communities. • Panel, spatial, and IV-threshold models confirm robust causal effects. • Mechanisms: better finance access, green innovation, and industrial upgrading. • Effects are heterogeneous by region; policy should be place-specific. • Implications for resilient and sustainable coastal development policy.