Du Hai-Bo, Yang Shan, Li Zheng-Ya, Guo Ze-Cheng, Fan Qing-Yu
School of Geography, Nanjing Normal University, Nanjing 210023, China.
School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China.
Huan Jing Ke Xue. 2024 Dec 8;45(12):6848-6857. doi: 10.13227/j.hjkx.202312107.
Clarifying the dynamic relationship between carbon sources/sinks and urban development is crucial to achieving carbon neutrality and sustainable development in the region. This study used net ecosystem productivity （NEP） to evaluate the carbon sinks of the terrestrial ecosystem in the Yangtze River Delta （YRD） from 2005 to 2020. Geodetectors were used to explore the impact of urban expansion, socio-economic factors, and their interactions on carbon sources/sinks in the YRD and to evaluate the gap in achieving carbon neutrality in cities. The results showed that： ① In 2005-2020, the NEP contribution of the YRD was 69.13 Mt·a and the loss of carbon sinks due to urban expansion was 1.97 Mt. The carbon emissions offset by carbon sinks were approximately 3% to 6%. ② The high carbon source areas were mainly distributed in the central and eastern YRD and the high carbon sink areas were primarily distributed in Zhejiang Province and southern Anhui Province. The forest-rich cities of Huangshan and Lishui, with smaller gaps between carbon emissions and carbon sinks, had the greatest potential for achieving carbon neutrality. Industrial or resource-based cities such as Xuzhou and Maanshan faced greater pressure to achieve carbon neutrality. Developed cities such as Shanghai and Suzhou had the largest carbon neutrality gap. ③ Urban expansion, economic and industrial agglomeration, high-density distribution of the population, and compact urban form were the key variables leading to the widening gap between carbon emissions and carbon sinks in the YRD. The increase in ecological space could effectively reduce carbon emissions. Urban expansion and socioeconomic development could be coupled with each other and have significant synergistic effects on carbon emissions.
厘清碳源/汇与城市发展之间的动态关系对于该地区实现碳中和及可持续发展至关重要。本研究利用净生态系统生产力（NEP）评估了2005年至2020年长江三角洲（YRD）陆地生态系统的碳汇。采用地理探测器探究城市扩张、社会经济因素及其相互作用对长三角地区碳源/汇的影响，并评估城市在实现碳中和方面的差距。结果表明：①2005—2020年，长三角地区NEP贡献量为69.13 Mt·a，城市扩张导致的碳汇损失为1.97 Mt。碳汇抵消的碳排放量约为3%至6%。②高碳源区主要分布在长三角地区的中部和东部，高碳汇区主要分布在浙江省和安徽省南部。黄山和丽水等森林资源丰富的城市，碳排放与碳汇之间的差距较小，实现碳中和的潜力最大。徐州和马鞍山等工业或资源型城市在实现碳中和上面临更大压力。上海和苏州等发达城市的碳中和差距最大。③城市扩张、经济和产业集聚、人口高密度分布以及紧凑的城市形态是导致长三角地区碳排放与碳汇差距扩大的关键变量。生态空间的增加可有效减少碳排放。城市扩张与社会经济发展可以相互耦合，并对碳排放产生显著的协同效应。
