The internal dynamics and regional differences of China's marine economic evolution based on comprehensive evaluation

The marine economy has always occupied an important position in China's economic development. It is not only an important element of the national economy but also the primary economic form in coastal areas. In recent years, China's economy has been growing at a rapid pace, and the marine economy's share of GDP has expanded as well. However, it is undeniable that the sustainable development of marine economy is also confronted with unprecedented challenges, such as sea pollution and the degradation of coastal ecosystem, etc. This article aims to prevent the predatory growth of the marine economy, to promote sustainable development, and to achieve the coordination and unity between marine economy and marine ecology, culture, resources and technology. This study explores the internal motivation of the sustainable evolution of marine economy and develops a new indicator system using data from 11 coastal areas in China from 2008 to 2018. The level of sustainability of the marine economy in China's coastal areas is evaluated using a combination of entropy and the improved topsis method. Results show that technological innovation driving has gradually replaced the resource-invested growth model. From 2008 to 2018, the sustainability of marine economic development in China's coastal areas showed a stratified trend, with obvious differences between different regions. Among them, the sustainability of Guangzhou was as high as 0.445, the development efficiency of Tianjin and Shanghai was higher, and the total marine economy of Zhejiang and Jiangsu was high but the sustainability was weak. Finally, we discussed the causes that contribute to regional disparities and offered recommendations.