Spatial convergence and its determinants of green urban land use efficiency: empirical evidence from 284 cities in China

The green use of land plays a crucial role in sustainable development of urban economy and society. However, further research is needed to deepen the understanding of its measurement and spatial evolution. This study examines the spatiotemporal distribution characteristics and spatial convergence patterns of green urban land use efficiency (ULUE) in China's 284 cities based on Super-SBM model that includes undesired output, Kernel density estimation (KDE), Dagum Gini coefficient and its decomposition, and beta convergence model. The results showed that during the sample period, the green ULUE of China presented a fluctuating upward trend, increasing from 0.508 to 0.679, a growth of 35.8%. There is significant heterogeneity in green ULUE among China's geographical regions, with the highest in the eastern region, followed by the west, and the lowest in the central region. In terms of regional differences, the overall Gini coefficient increased from 0.074 to 0.084, and mainly due to intensity of transvariation, followed by intra-regional differences, with the contribution of inter-regional differences relatively small. We also find that whether in the absolute or conditional beta convergence model, the coefficients of beta from the national sample or the three major regions are all significantly negative, revealing that there is obvious absolute and conditional beta convergence process in green ULUE in the period from 2003 to 2019. These findings have important policy implications for accurately grasping the urban land use condition in China, improving green ULUE and narrowing the gap in urban land use between different regions.