Abstract: The study on spatial distribution and carbon sequestration capacity of urban green space is of great significance to the evaluation of ecological service value. Taking Nanan District of Chongqing as the research area, the Landsat8 remote sensing images of 2013 and 2016 were supervised and classified, and the land use data of the two periods were obtained, and then the transfer matrix analysis of land use was carried out. Finally, the ecological benefits of urban green space in carbon sequestration were quantitatively estimated by using CITYgreen model. The results show that: (1) from 2013 to 2016, the construction land in Nanan District has increased by 1025.01 ha, while the urban green space has decreased by 333 ha as a whole; (2) the decrease of urban green space in Nanan District is mainly reflected in the conversion of forest land to construction land and cultivated land; (3) the annual carbon sequestration of urban green space in Nanan District in 2013 and 2016 are converted into ecological benefits of about 4.782 million yuan and 4.5436 million yuan. The research results reveal the spatial distribution, evolution and carbon sequestration benefits of urban green space in Nanan District, so as to provide a scientific basis for governments decision.

Key words: environmental engineering, urban green space, remote sensing, CITY green model, carbon sequestration benefit, supervisory classification

摘要： 研究城市绿地的空间分布变化和固碳能力，对于其生态服务价值评估具有重要意义。以重庆市南岸区为研究区域，对2013年、2016年两个时期的Landsat8遥感影像进行监督分类，得到研究区两期土地利用数据，进而对土地利用进行转移矩阵分析，最后借助CITYgreen模型定量估算了城市绿地在固碳方面创造的生态效益。结果表明:2013—2016年，南岸区建设用地增长1025.01 ha，而城市绿地整体减少333 ha；南岸区城市绿地的减少主要表现为林地转为建设用地和耕地；南岸区城市绿地年固碳带来的生态效益分别为478.2万元和454.36万元。研究结果揭示了南岸区城市绿地的空间分布、演变及其固碳效益变化，为政府决策提供科学依据。

关键词: 环境工程, 城市绿地, 遥感, CITYgreen模型, 固碳效益, 监督分类