Exploring the Effects of Socioeconomic Factors and Urban Forms on CO 2 Emissions in Shrinking and Growing Cities

Exploring the mechanisms influencing carbon dioxide (CO 2 ) emissions is crucial to seeking low-carbon development paths. Previous studies have analyzed the effects of socioeconomic factors and urban forms on CO 2 emissions. However, little attention has been paid to the heterogeneity of their interactions in differing urban development patterns, such as growth and shrinkage. This study focused on how socioeconomic factors and urban forms work together to comprehensively affect CO 2 emissions within the context of urban shrinkage and growth. A selection of 285 prefecture-level cities in China were divided into four groups of shrinking and growing cities based on a comprehensive index system. After assessing variables involving socioeconomic factors and urban forms, a panel data model was used to verify their mutual mechanisms influencing CO 2 emissions. The results show that CO 2 emissions in shrinking cities continue to rise due to the driving force of secondary industry and the coexistence of population loss and space expansion. For growing cities, in addition to economic development and population growth, urban forms with excessive compactness and polycentricity significantly accelerate CO 2 emissions. Consequently, disorderly urban expansion should be avoided, and industrial upgrading should be promoted for shrinking cities. Meanwhile, growing cities are advised to develop modern service industries. Moreover, it is recommended that urban spatial planning follows urban functions and their development stages to avoid excessive agglomeration and polycentricity.