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Remote Sensing for Natural Resources    2023, Vol. 35 Issue (3) : 253-263     DOI: 10.6046/zrzyyg.2022222
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Analyzing the spatio-temporal evolution patterns of urbanization in the Loess Plateau based on night light data and statistical data
ZHAO Anzhou1,2(), ZHANG Xiangrui1, XIANG Kaizheng1, LIU Xianfeng3, ZHANG Jinghan1
1. School of Mining and Geomatics, Hebei University of Engineering, Handan 056038, China
2. Research Center of Water Ecological Civilization and Social Governance of Hebei Province, Hebei University of Engineering, Handan 056038
3. School of Geography and Tourism, Shaanxi Normal University, Xi’an 710119, China
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Abstract  

Research on the spatio-temporal evolution of urbanization is significant for optimizing the spatial structure of a city. Through the saturation and consistency correction of DMSP/OLS and NPP/VIIRS data, this study constructed a remote sensing dataset of night light in the Loess Plateau from 2000 to 2019. Then, this study calculated the compound night light index (CNLI) on different spatial scales and extracted the area of build-up areas in the Loess Plateau using a dichotomy method. Furthermore, this study analyzed the spatial evolution patterns using methods such as standard deviational ellipse (SDE). The results are as follows: ① The CNLI calculated from night light data correlated strongly with the urbanization development index (UDI) and various sub-indicators. ② The CNLI values of the Loess Plateau and five urban agglomerations showed significant upward trends during 2000—2019 and spatial downward trends from southeast to northwest. ③ The area of build-up areas in the Loess Plateau extracted using the dichotomy method had mean absolute and relative errors of 2.45 km2 and 3.72%, respectively. ④ The focus of the built-up areas in the Loess Plateau showed a southeastward shifting trend during 2000—2019, with the SDE-covered area decreasing significantly (slope = 0.0107 km2/a; p < 0.01) and the azimuth angle changing from northeastern 83.33° to 88.37°. The results of this study can provide data support and a methodological reference for investigating the spatio-temporal patterns of urbanization in the Loess Plateau and other ecologically vulnerable areas.
Keywords night light data      urbanization      CNLI      UDI      spatio-temporal evolution      Loess Plateau     
ZTFLH:  TP79  
  F129.9  
Issue Date: 19 September 2023
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Anzhou ZHAO
Xiangrui ZHANG
Kaizheng XIANG
Xianfeng LIU
Jinghan ZHANG
Cite this article:   
Anzhou ZHAO,Xiangrui ZHANG,Kaizheng XIANG, et al. Analyzing the spatio-temporal evolution patterns of urbanization in the Loess Plateau based on night light data and statistical data[J]. Remote Sensing for Natural Resources, 2023, 35(3): 253-263.
URL:  
https://www.gtzyyg.com/EN/10.6046/zrzyyg.2022222     OR     https://www.gtzyyg.com/EN/Y2023/V35/I3/253
Fig.1  Geographical location of cities and urban agglomerations in the Loess Plateau
准则层 权重 指标层 单位 属性 权重
人口城镇化 0.172 城镇人口占比 % + 0.043
人口密度 人/km2 + 0.098
非农就业人员占比 % + 0.031
经济城镇化 0.268 非农产业产值占比 % + 0.084
人均公共预算收入 万元 + 0.104
人均GDP 元/人 + 0.080
空间城镇化 0.258 建成区面积 km2 + 0.042
人均绿地面积 m2/人 + 0.118
人均道路面积 m2/人 + 0.098
社会城镇化 0.302 每万人医疗卫生床位数 张/万人 + 0.114
人均商品销售总额 元/人 + 0.134
每万人高校学生数量 人/万人 + 0.054
Tab.1  UDI system of the Loess Plateau
函数类型 模型表达式 R2
线性函数 y=0.121 1x-1.193 4 0.709 5
指数函数 y=0.213 2 e 0.054 8 x 0.756 9
对数函数 y=2.372 3lnx-5.480 7 0.441 1
二次多项式 y=0.001 9x2-0.018 2x+0.410 7 0.853 6
Tab.2  Fitting results of DMSP/OLS and NPP/VIIRS in 2013
Fig.2  Scatter plot between UDI and CNLI in the Loess Plateau from 2000 to 2019
Fig.3  Changes of the CNLI in Loess Plateau and five urban agglomerations from 2000 to 2019
Fig.4  Spatial pattern and change of lighting image and CNLI in the Loess Plateau from 2000 to 2019
Fig.5  Absolute error and relative error for built-up areas extraction in the Loess Plateau from 2000 to 2019
Fig.6  Urban expansion of the Loess Plateau and six provincial capitals from 2000 to 2019
区域 2000—2010年 2010—2019年 2000—2019年
黄土高原 6.27 4.69 7.42
关中平原城市群 7.02 5.84 9.03
晋中城市群 3.33 4.07 4.61
呼榆包鄂城市群 8.01 3.33 7.53
宁夏沿黄城市群 13.81 3.30 11.76
兰西城市群 2.47 4.98 4.52
西安 7.74 10.54 14.02
太原 3.71 3.65 4.61
呼和浩特 9.42 5.44 10.71
银川 13.27 6.59 15.40
兰州 2.77 6.24 5.60
西宁 1.34 4.00 3.03
Tab.3  Urban expansion intensity in the whole Loess Plateau, five urban agglomerations and six provincial capitals during 2000—2010, 2010—2019 and 2000—2019(%)
Fig.7  Spatio-temporal dynamics of standard deviation ellipse elements, centroid migration route, areal change trend and azimuth change from 2000 to 2019
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