北京城市副中心及周边区域蓝绿空间景观格局及降温效应评估

Landscape Pattern and Cooling Effect Evaluation of Blue-Green Space in Beijing’s Sub-center and Surrounding Area

科学评估北京城市副中心及周边区域建设不同阶段景观格局和热环境,对其今后的发展规划和相关政策制定具有重要意义。以北京城市副中心外围规划为基准稍作调整作为研究区,选取2016年、2018年、2020年和2022年共4期资源三号遥感影像数据,以及Google Earth Engine(GEE)中4年6月1日-9月30日的Landsat 8遥感影像数据,通过面向对象分类、地表温度反演、相关性分析方法定量分析不同时期的蓝绿空间景观格局以及蓝绿空间的降温效应。结果表明:(1)2016-2022年,研究区蓝空间的面积占比在保持稳定的同时逐渐增加,绿空间的面积占比先减少后增加;(2)2016-2022年,北京城市副中心及周边区域蓝绿空间景观格局中各斑块类型在景观中的分布越来越均衡;(3)2016-2022年间,地表温度均值呈“上升—下降—上升”的波动变化,蓝空间的地表温度最低,其次是绿空间,蓝空间和绿空间在一定程度上起到降温的作用;(4)提高聚集度、减少人类活动的割裂程度、减小空间破碎度均可提升蓝绿空间的降温效应。总体而言,北京城市副中心及周边区域建设使得蓝绿空间面积增加,景观格局分布更加均衡,蓝绿空间的降温效果较为明显。

Scientific assessment of land cover,landscape pattern,and thermal environment in different stages of Beijing’s sub-center and surrounding areas’construction is signifi cant for future development planning and related policy making.Taking the peripheral planning of Beijing’s Sub-center as the baseline and slightly adjusted as the research area,the remote sensing image data of ZY-3 in 2016,2018,2020,and 2022 were selected,and Landsat 8 remote sensing image data from June 1 to September 30 in Google Earth Engine(GEE).Through object-oriented classifi cation,land surface temperature inversion,and correlation analysis methods,the blue and green spatial landscape pattern and the cooling effect of the blue and green space in different periods were quantitatively analyzed.The results showed that:(1)From 2016 to 2022,the area proportion of blue space in the study area gradually increased while maintaining stability,while the area proportion of green space fi rst decreased and then increased;(2)From 2016 to 2022,the distribution of various patch types in the UBGS landscape pattern of Beijing’s sub-center and its surrounding areas has become more and more balanced;(3)During 2016 to 2022,the mean land surface temperature(LST)showed a“rising-falling-rising”fl uctuation.The LST of blue space was the lowest,followed by green space,which played a cooling role to a certain extent;(4)Improving the degree of aggregation,reducing the degree of fragmentation of human activities,and reducing the degree of spatial fragmentation can improve the cooling effect of UBGS.In general,the construction of Beijing’s sub-center and surrounding area increases the UBGS area,the landscape pattern distribution is more balanced,and the cooling effect of UBGS is more prominent.