Du, Z.; Zhu, X., and Shan W., 2020. External diseconomy theory and environmental management: Optimal taxation model in china marine management. In: Wan, Z. (ed.), Coordinated Sustainable Development in Coastal Areas: Environment and Economy. Journal of Coastal Research, Special Issue No. 109, pp. 174–180. Coconut Creek (Florida), ISSN 0749-0208.

The pollution of coastal production activities and marine related industries is very serious, which is an economic externality. Externality theory is the theoretical basis of environmental economics. On the one hand, the externality theory reveals the root causes of some inefficient resource allocation in market economic activities; on the other hand, it provides alternative ideas for how to solve the problem of external environmental diseconomy. Marine environmental pollution is a typical external diseconomic phenomenon, which is manifested as the decline of living quality of surrounding residents, the increase of disease incidence, the decline of seafood production and quality, the impact of aquatic life death on fishery income, the increase of sewage treatment costs, the acceleration of equipment depreciation, and the decrease of tourism income. Based on the theory of externality, this paper applies the theory of externality in marine environmental management in China and discusses the improvement measures of the integrated management of marine environment in China.