关键词: 降温效应, 节能减碳, 城市绿地, 长三角

Abstract: The vegetation carbon sink has been estimated from the absorption and storage of CO₂ through photosynthesis. However, due to its ecological functions such as the local cool island effect of the urban greenspace, little attention has been paid to the energy saving and carbon reduction, and there is a lack of estimation of carbon saving amount in regional cities. Based on the important ecological function of cooling effect of urban green space, this study used buffer analysis and statistical analysis methods to analyze the carbon saving of urban greenspace in 27 core cities in the integrated central area of the Yangtze River Delta (CCICAYRD). Results show that the urban greenspace in the downtown of CCICAYRD had a significant cooling effect. The average LST of urban greenspace was 2.18 K, lower than that of the downtown, and the cooling range was between 2.9 and 8.3 K, and the cooling distance of greenspace patches was between 270 and 450 m. The carbon saving estimation show that the total carbon saving of the 27 core cities in the CCICAYRD was approximately 267 656.12 t·d^-1, with an average carbon saving of 9 913.19 t·d^-1 per city. Among the major cities, the carbon saving of urban greenspace in Shanghai downtown was the largest, reached to 47 374.83 t·d^-1, followed by Wenzhou, Ningbo, Nanjing, Hangzhou, Tāizhou, Suzhou, Wuxi and Hefei, while the carbon saving of urban greenspace patches was small in Xuancheng, Shaoxing, Jiaxing, Chizhou, Ma'anshan and Anqing, all below 2 000 t·d^-1. In addition, as the distance to the greenspace patches increased, the carbon saving of the urban greenspace gradually decreased from 3 562.54 t·d^-1 in the cooling distance of 0-90 m to 54.20 t·d^-1 in the cooling distance of >180-270 m. This conclusion can provide a scientific reference for the urban ecological construction and the researches on urban carbon peaking and neutrality.

Key words: cooling effect, energy saving and carbon reduction, urban greenspace patches, Yangtze-River Delta