Coastline eco-efficiency and sustainable development of Bohai Rim cities

Improving coastline eco-efficiency and pursuing sustainable development are key factors for ensuring that coastal cities efficiently develop tertiary industries and improve their urban competitiveness. In this study, we applied an eco-efficiency measurement model to evaluate coastline eco-efficiency and analyzed the coordinated social economy (SE) and ecological environment (EE) development data of 13 Bohai Rim cities to explore issues facing sustainable development and determine appropriate countermeasures. The findings revealed notable variations in the coastline eco-efficiency among the prefecture-level cities from 2010 to 2019. Based on the results obtained from the SE and EE systems, we classified the development status of the cities into four categories: orderly development (I), EE lag (II), SE lag (III), and development lag (IV). The region is facing four main challenges associated with an imbalance in the urban scale structure, individual development trend, industrial structure layout, and motivational force of urban development. To ensure the future of the Bohai Sea region, integrated urban agglomeration, functional areas, and region-wide marine economic cooperation should be promoted. Moreover, it is crucial to enhance the application capacity and allocation efficiency of existing technologies, thereby improving coastline eco-efficiency and fostering high-quality urban development.