The impact of land structure and function mixing on carbon emission efficiency: an examination of 268 Chinese cities

Extreme heat and disease transmission triggered by global warming pose severe threats to human health, creating an urgent need to promote low-carbon development. It is widely recognized that mixed land-use strategies play a critical role in reducing carbon emissions and mitigating global warming. In contrast to existing literature that solely focuses on either land structure mix or land function mix, this research integrates both into a unified analytical framework for comparative analysis. This approach aims to clarify the key directions that mixed land-use strategies should prioritize. By employing the information entropy method, this study utilizes remote sensing imagery and Point of Interest (POI) data to characterize structural and functional mixed land use across 268 prefecture-level cities in China, and further analyzes their impacts on carbon emission intensity. The experimental results show that land structure mix significantly reduces the carbon emission intensity; in contrast, the land function mix increases the carbon emission intensity. The mechanism analysis shows that the former generates positive externalities by promoting economic agglomeration, offsetting the negative effects of traffic congestion, whereas the latter intensifies the urban traffic pressure and does not show significant agglomeration effects. The spatial econometrics results further show that a significant spatial spillover effect of functional mixing, which further amplifies the carbon emission pressure in the city. The article further proposes policy recommendations.