Evaluation and Spatial Correlation Analysis of Green Economic Growth Efficiency in Yangtze River Delta Urban Agglomeration

The Yangtze River Delta urban agglomeration has an extremely important strategic location in the national regional development pattern, is the engine of China's green economic development, and plays an important role in promoting the green transformation of the national economy. It is important to clarify the region's current situation and the space-time characteristics of green economic growth. This study uses a super-efficiency dynamic Slacks-Based Measure (SBM) model to measure the green economic growth efficiency (GEGE) of 41 cities in the Yangtze River Delta urban agglomeration. Based on this, the exploratory spatial data analysis (ESDA) method is used to analyze the spatial correlation of the GEGE. Differently from previous studies, this paper evaluates the GEGE based on a dynamic perspective, considering the intertemporal role of capital. At the same time, the space-time analysis of regional systems (STARS) is used to explore the long-term development pattern and transition path of the GEGE in the Yangtze River Delta urban agglomeration. The results show the following: (1) The GEGE in the Yangtze River Delta urban agglomeration shows a fluctuating downward trend. The efficiency values of the Shanghai, Jiangsu, Zhejiang, and Anhui are significantly different, showing the distribution law of "high in the east and low in the west". (2) The global spatial autocorrelation has weakened, but the characteristics of local agglomeration are obvious. (3) The space-time transitions show high spatial stability and path dependence. The findings highlight that the economic development of the Yangtze River Delta urban agglomeration is undergoing a difficult period of transition. Despite a decline in the GEGE, the overall regional linkage shows a positive trend. The conclusions can provide a reference for enhancing the green economic development of the Yangtze River Delta urban agglomeration. The implications of this research are important for the implementation of a regional integration strategy and the early achievement of the emission peak and carbon neutrality goals.