Efficiency and equity: Effect of urban agglomerations' spatial structure on green development efficiency in China

Increasing attention has been paid to optimizing the spatial structure of urban areas and transitioning them toward green development. Quantitatively analyzing the influence of spatial structure on green development efficiency (GDE) can help solve scientific problems related to urban agglomerations (UAs). Using panel data for 19 UAs in China from 2007 to 2020, this study investigates spatial structure's effect on GDE based on the spatial structure morphology dimension and constructs a mechanism based on technological progress. Considering variance in GDE growth among clusters, the effect of spatial structure on the GDE gap between UAs is examined in terms of unbalanced growth. The results indicate that: (1) A negative correlation exists between the monocentric UA spatial structure and GDE. (2) Technological progress is the main mechanism, while efficiency improvement does not show a significant path. (3) Increased monocentricity will widen the gap in intergroup GDE. These findings can help inform coordinated regional green development in terms of urban planning.