Dual impacts of urban expansion on the carbon sequestration capacity of urban vegetation: A multi-scale global study

作者：Jieming Kang, Qian Zhang, Baolei Zhang, Yuanman Hu, Chuyi Zhang, Chunlin Li · 发表于：Ecological Indicators · 年份：2025 · DOI：10.1016/j.ecolind.2025.113746 · 被引用次数：17 · 研究领域：Land Use and Ecosystem Services、Urban Green Space and Health、Urban Heat Island Mitigation

Urban expansion irreversibly alters the structure and function of terrestrial ecosystems, yet the specific impact on the carbon sequestration capacity of vegetation (characterized by net ecosystem productivity, NEP) in and around urban areas remains unclear. Previous studies confined to urban boundaries may have underestimated the full ecological impacts of urban expansion; therefore, this study explores the impact of urban expansion on the NEP at multiple scales across urban boundaries for 2904 cities globally using multiple global remote sensing datasets. The results indicated that differences within urban areas lead to significant heterogeneity in the inter-annual changes in NEP. There were insignificant changes in urban areas, a slow upward trend in old urban, insignificant changes in new urban, and a slow upward trend in suburban. When further differentiated by country level, NEP shows a clear upward trend in all urban areas of developed cities, whereas in developing cities, no urban area shows a clear upward trend. The impact of urban expansion extends significantly beyond urban boundaries, with megacities and supercities exhibiting a radius of influence of 70–80 km, compared to only 30–40 km for large, medium, and small cities. The negative impacts of global urban expansion caused a significant decrease in NEP over an area of 320,350 km 2 , while the positive impacts increased NEP over an area of 86,710 km 2 , offsetting the negative effects by approximately 27.1 %. Th...