基于核密度估计的福州市POI与夜光数据空间耦合分析

Analysis of Spatial Coupling Between POI and Nightlight Data in Fuzhou Based on Kernel Density Estimation

POI和夜光数据能直观表达社会经济要素的空间分布特征,但将两者进行空间耦合来分析城市空间结构的研究较为缺乏。本研究利用2022年福州的POI和夜光数据,基于不同带宽和数据变换方法下的POI核密度的空间自相关性、标准差及与夜光数据的相关性来获取用于空间耦合分析的POI与夜光数据源,空间耦合后比较两类数据表征城市内部空间结构特征的差异。结果表明:1)核密度带宽设置为2000 m时,对数变换的POI核密度的Moran's I、标准差和与夜光数据的相关性达到综合最优。2)POI和夜光亮度在主城区和县区中心密集分布,高值区的特征值/面积比达到3∶1,福州高度发展区域体现出一中心、多点位的空间分布特征。3)POI与夜光数据空间耦合一致性区域占81.78%,且该区域内POI数据对空间结构特征的表达优于夜光数据。4)POI数据比夜光数据更适用于反映福州西部和北部的边缘乡村和发展中心辐射区域的空间结构特征,夜光数据则比POI数据更适用于福州东部的生态区和商业区的空间特征表达。研究结果得到了POI和夜光数据在各类空间耦合区域的适用性,可为城市空间结构特征的高精度表达提供参考。

POI and night-light data can visually express the spatial distribution characteristics of socio-economic elements,but the research on spatial coupling of the two data to analyze the urban spatial structure is relatively insufficient.POI and night-light data of Fuzhou in 2022 are used to obtain spatial coupling analysis sources based on spatial autocorrelation,standard deviation and correlation with night-light data of POI kernel density through different bandwidths and data transformation methods,and the differences in the spatial structure features of the two types of data are compared after spatial coupling.The results showed that,1)when the kernel density bandwidth was set to 2000 m and the Lg transform method is chosen,the Moran's I index,standard deviation and the correlation with night-light data of the POI kernel density reach the comprehensive optimum.2)POI and night-light brightness are densely distributed in the main urban areas and county centers,and the value/area ratio is about 3∶1 in high value areas and the highly developed areas of Fuzhou reflect the spatial distribution characteristics of one center and multiple points.3)The spatial coupling consistency area of POI and night light data accounts for 81.78%,and the expression of spatial structural features of POI data within the region is better than that of night light data.4)POI data is more suitable than night light data to reflect the spatial structural features of the marginal rural areas in the western and northern of Fuzhou and the radiation areas of the development centers of Fuzhou whereas the night light data is more applicable to express the spatial features of ecological zones and commercial zones in the eastern part of Fuzhou than POI data.The results of the study obtained the applicability of POI and night-light data in various types of spatially coupled regions,which can provide reference for high-precision expression of urban spatial structure features.