Abstract:

Understanding the spatiotemporal differentiation characteristics and driving mechanisms of land use carbon emissions in urban agglomerations is critical for promoting regional land intensive use and low-carbon development. Based on multi-source data such as remote sensing， energy， and economic statistics， adopting carbon emission coefficient methods， nighttime light remote sensing inversion， and the Logarithmic Mean Divisia Index （LMDI） decomposition model， this study systematically analyzes the spatiotemporal evolution patterns and driving factors of land use carbon emissions in the Lanzhou-Xining Urban Agglomeration from 2000 to 2022. The results show that： （1） The land use structure was dominated by grassland and cropland， followed by forest， water bodies and barren land， finally construction land. In terms of net change rate， the order was construction land （2.94%） > barren land （0.81%） > water bodies （0.50%） > forest （0.23%） > grassland （0.05%） > cropland （-0.63%）. （2） Direct carbon emissions from land use showed a declining trend， with an average annual decrease of 3.26%. In contrast， carbon emissions from construction land and total land use carbon emissions showed continuous growth， with average annual increases of 4.27% and 4.26% respectively. Construction land was the main carbon source， and regions with high carbon emissions were concentrated in the counties administered by Gansu Province and the core zone of Xining-Ledu. （3） The economic development level （the primary contribution factor） and construction land expansion were the primary positive drivers for the increase in total land use carbon emissions， which cumulatively contributing to the total land use carbon emission increase of 32 104.72×10⁴ t. While carbon emission intensity （the dominant suppressing factor） and land use efficiency played significant inhibitory roles， which cumulatively leading to the total land use carbon emission decrease of 25 244.80 × 10⁴ t. Therefore， enhancing land use efficiency and strictly controlling carbon emission growth resulting from construction land expansion during economic development are crucial pathways for achieving emission reduction in the Lanzhou-Xining Urban Agglomeration.

Key words: land use carbon emissions, temporal evolution, spatial heterogeneity, driving factors, Lanzhou-Xining Urban Agglomeration