A study of the impact of environmental regulation on land-based marine pollution—evidence from 11 coastal provinces in China

Based on panel data on Land-Based Marine Pollution from 11 coastal provinces in China spanning 2012 to 2023, this study employs Fixed-Effects, Threshold Regression, and Mediation Models to investigate the impact of Environmental Regulation on Land-Based Marine Pollution. The results show that: (1) there exists an inverted U-shaped relationship between Environmental Regulation and Land-Based Marine Pollution, where regulation beyond a certain threshold continuously reduces pollution levels; (2) threshold regression analysis reveals a single threshold effect in the negative impact of Environmental Regulation on the management of Land-Based Marine Pollution; (3) mediation analysis indicates that Green Technological Innovation and Industrial Structure play a mediating role between Environmental Regulation and pollution management. Specifically, Environmental Regulation reduces Land-Based Marine Pollution by promoting Green Innovation in enterprises and facilitating Industrial upgrading. To improve the management of Land-Based Marine Pollution in China, it is recommended to appropriately strengthen Environmental Regulation intensity and encourage enterprises to engage in Green Technological Innovation and Industrial restructuring, thus balancing environmental management with economic development and providing a scientific basis for pollution control.