Study on the Measurement and Enhancement Pathways of Ecological Efficiency of Marine Fisheries in China’s Coastal Areas

Marine fisheries play a vital role in ensuring food supply and sustaining livelihoods in coastal regions of China. However, the expansion of aquaculture has led to increasing carbon emissions and mounting pressure on resources and the environment, making the improvement of ecological efficiency a critical issue for the sustainable development of the industry. From the perspective of carbon emissions as undesirable output, this paper employs the DEA-SBM model and the GML index to measure the ecological efficiency of marine fisheries across nine coastal provinces in China from 2006 to 2023. Furthermore, using fixed-effects models, mediation-effect models, and grouped regression models, this study empirically examines the impacts of fishermen’s income and environmental regulations on the ecological efficiency of marine fisheries and their transmission mechanisms. The results indicate that ecological efficiency exhibits fluctuating trends across provinces, with significant inter-provincial disparities. Fishermen’s income has a significant positive effect on ecological efficiency, while environmental regulations show a significant negative effect. Digitalization level significantly promotes ecological efficiency, whereas fishery disaster losses significantly inhibit it. Technological adoption intention plays a partial mediating role in the pathways through which both fishermen’s income and environmental regulations affect ecological efficiency. Significant regional heterogeneity is observed, with the eastern coastal region exhibiting the strongest effects of various factors and the northern coastal region showing the weakest. Accordingly, this paper proposes differentiated enhancement pathways for ecological efficiency from four dimensions, including technological innovation-driven development, industrial structure optimization, environmental policy regulation, and regional coordinated governance, with the aim of providing theoretical foundations and policy references for the low-carbon transformation and sustainable development of marine fisheries in China’s coastal areas.