Research on sustainable development of marine ranching based on blue carbon trading

Promoting the trading of blue carbon generated by marine ranching (MR) is essential for China to achieve its carbon peaking and carbon neutrality goals. As blue carbon trading develops, it remains uncertain whether it can promote the transformation of marine ranching firm (MRF) from traditional fishery aquaculture-type MR (FAMR) to more eco-friendly conservation-type MR (CMR). This paper constructs a game model involving MRF and the government to explore the impact of blue carbon trading on the transformation of MRF' production modes by considering carbon asset renting, carbon cap-and-trade, government subsidies, and green investment, which is of great significance in managing coastal marine and aquatic organisms, as well as promoting sustainable development of the marine economy. Research shows that the price and demand of FAMR products are solely influenced by carbon cap-and-trade. The introduction of carbon rents will increase the incentive for MRF to choose CMR, and this incentive is further enhanced when government subsidies are provided. Concurrently, green investment and MRF's profit have an inverted-U relationship. Both government subsidies and blue carbon trading will increase blue carbon. Although this policy will also increase MRF's carbon emissions, the carbon surplus generated by MRF will be higher than without subsidies.