Research on the Coupling Coordination of a Sea–Land System Based on an Integrated Approach and New Evaluation Index System: A Case Study in Hainan Province, China

Based on the concept of sea–land coordination and the statistical data of Hainan Province from 1999 to 2013, we establish a new evaluation index system included four aspects—economic development, social progress, environmental protection and resource efficiency—and use the integrated approach (such as the combination weight method, the coupling coordination degree model, the scissors difference model and the dynamic coupling coordination degree model) to measure the coupling coordination degree of a sea–land system. The results show that: (1) the overall development level of sea system and land system are gradually improved; (2) the coupling coordination degree of sea–land system is gradually from moderately uncoordinated to well coordinated, and the comprehensive evaluation value of sea system has a greater effect on the coupling coordination degree D than that of land system; (3) the scissors difference between sea system and land system is gradually increasing; (4) the dynamic coupling coordination degree of the sea–land system which favors a parabolic shape is basically in the break-in development stage; (5) in the process of sea–land system coordination, the influencing factors of economic development, the social progress and resource efficiency should be given priority and, at the same time, strengthen the environmental protection efforts and awareness to promote the role of environmental protection in the sea–land coordination.