新冠疫情对城市群夜间灯光影响及时空异质性分析——以长江中游城市群为例

Impact of COVID-19 on Nighttime Lighting and Spatio-temporal Heterogeneity Analysis in Urban Agglomeration:Taking Yangtze River Middle Reaches Megalopolis, China for an example

科学评估重大突发公共卫生事件的空间影响是提升城市韧性的重要基础。为探究COVID-19疫情对城市空间及时空异质性影响,文章基于NPP-VIIRS夜间灯光数据,采用辐射亮度总值、时序差值及散点回归系数等方法对长江中游城市群受疫情影响情况进行多尺度综合分析。结果表明:长江中游城市群辐射总值指数在疫情前后呈“匀速增长-显著下跌-快速恢复-小幅回落”4个变化阶段;长江中游城市群灯光变化的空间规律差异明显,鄱阳湖、长株潭和武汉都市圈灯光拟合系数在封锁期间呈“W”和“V”型两种规律,5月灯光恢复程度鄱阳湖>长株潭>武汉都市圈;封锁对武汉市城郊灯光影响效应呈“中心-边缘”衰减规律,其中城区受到冲击较大,回归系数出现断崖式下跌,且恢复时间晚于郊区。

Scientific assessment of the spatial impact of major public health emergencies is an important basis for enhancing urban resilience. In order to investigate the spatial and spatial heterogeneity of the COVID-19 epidemic on urban space, this paper presents a multi-scale comprehensive analysis of the epidemic impact on the middle reaches of the Yangtze River middle reaches megalopolis based on NPP-VIIRS nighttime lighting data using total night light(TNL),time-series difference and scattered regression coefficients. The results show that:(1)The TNL of the middle reaches of the Yangtze River middle reaches megalopolis shows four stages of change before and after the epidemic, which is uniform growth-significant decline-rapid recovery-slight decline.(2)The spatial pattern of lighting change in the middle reaches of Yangtze River middle reaches megalopolis varies obviously, the light restoration degree in May Poyang Lake>Chang-Zhu-Tan>Wuhan metropolitan area. The light fitting coefficients of Wuhan Metropolitan Area, Chang-Zhu-Tan and Poyang Lake city cluster show “W” and “V” patterns of change during the epidemic blockade.(3) The effect of Wuhan suburban epidemic on lighting shows a “center-edge” decay pattern. During the epidemic, the urban area was hit harder, and the regression coefficient fell precipitously and recovered later than that of the suburban area.