Coupling Evaluation and Spatial-Temporal Evolution of Land Ecosystem Services and Economic-Social Development in a City Group: The Case Study of the Chengdu-Chongqing City Group.

Abstract

The Chengdu-Chongqing city group (CCCG) is one of the regions with acute human-land conflicts in China at present. The current rapid development of CCCG has caused a large negative impact on regional land ecosystem services. Land ecosystem is the basis of economic development. Reasonable economic development is also the inherent requirement of land ecosystem and an important support for land ecosystem protection. Promoting the coordinated development of the economy and land ecosystems is a prerequisite for this city group to achieve ecological protection and high-quality development. Taking CCCG as an example, this paper constructs a coupling evaluation model of economic-social development and land ecosystem service by using the entropy weight method, coupling coordination degree model, gravity center model, and standard deviation ellipse model, and explores the coupling coordination degree and spatial-temporal evolution rule of the above two systems. The study found that, from 2005 to 2020, the overall economic-social development of the CCCG showed an upward trend with a regular pattern of a 'High in the east and west, low in the central', and the 'dual-core' spatial structure with Chengdu and Chongqing as the core ; the overall performance of land ecosystem services had a gentle slope downward trend with a 'U'-shaped spatial pattern of "high around and low in the middle". The results also show that the coupling coordination degree of economic-social development and land ecosystem services in CCCG continues to rise steadily. Overall, the level of coupling coordination is low, and the type of coupling coordination has gradually evolved from severe and moderate imbalance to moderate coordination and mild imbalance. Therefore, the CCCG should make full use of the advantages of the "dual-core" cities to improve the level of peripheral economic linkage, increase investment in science and technology to enhance the endogenous power of economic development, establish cooperation mechanisms to narrow the urban gap, and integrate ecological resources to promote ecological industrialization to better realize the synergistic promotion of land ecological protection and high-quality economic development.