The Impact of High Environmental Standards in Trade Clauses on Bilateral Aquatic Product Value Chain Linkages

Aquatic product value-added trade constitutes a vital component of agricultural food security. Particularly in developing coastal nations, aquatic products serve as the backbone of the agricultural sector. However, illegal, unreported, and unregulated (IUU) fishing activities not only disrupt the global marine aquatic products value chain but also accelerate the degradation of marine ecosystems and the depletion of marine resources, posing severe challenges to sustainable fisheries and environmental governance. In 2022, the World Trade Organization reached a consensus on fisheries subsidy negotiations, while regional agreements such as the United States–Mexico–Canada Agreement (USMCA) and the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP) incorporated fisheries into relevant provisions under environmental rules. This indicates that high-standard environmental trade agreements are emerging as crucial tools for cross-border fisheries governance. This study employs open economy theory and a deep text protocol database to conduct an empirical analysis of the impact of high-standard bilateral environmental provisions on the interconnections within the aquatic products value chain. Findings reveal that environmental provisions significantly strengthen these linkages by lowering market access barriers, promoting technology spillovers, and reinforcing horizontal and vertical labor division. Heterogeneity analysis further shows that the extent of these effects varies with trade provisions, political distance, and network position. These insights offer new perspectives for seafood exports and upstream–downstream coordination in aquatic products, providing policy implications for regions seeking to enhance their value chain advantages.