Exploring Urban Expending Pattern of Gansu Province Using Time Series of Nighttime Light Remote Sensing Data
Gansu Province plays an important role in the national strategies.Analyzing the regular pattern of ur-ban expansion and temporal and spatial characteristics of Gansu Province is of great significance for the promo-tion of new urbanization and the implementation of Belt and Road strategy.An urban expansion model analysis framework composed of standard deviation ellipse,Kernel density analysis,geometric feature analysis of built-up area,position-scale law and correlation matrix was established,and the law of urban expansion over the past 10 years was systematically evaluated based on NPP-VIIRS-like nighttime light remote sensing data corrected across sensors.First,after moving from Lanzhou City to Baiyin City,the center of gravity of nighttime light moved back again,while the distribution direction was generally northwest-southeast,with obvious agglomera-tion phenomenon in this direction.Secondly,the scale of cities in the province has grown significantly.Its spa-tial pattern evolved from the dual-core pattern of"one main and one time"in Lanzhou and Jiayuguan to Lanzhou as the center,Jiayuguan and Qingyang as the two wings.What's more,the expansion rate of built-up areas in the province has gradually slowed down,and the expansion mode is divided into four groups related to geograph-ical location according to the geometric characteristics of built-up areas.And then,Prefecture-level cities obey the distribution of the order-scale law,and the distribution type is secondary,which means the primacy index of the provincial capital Lanzhou City is not significant.Finally,Total amount of lights at night and the displace-ment of the center of gravity in the east-west direction are closely related to socio-economic factors,while the displacement in the north-south direction is not strongly correlated.Research results comprehensively reveal the law of urban expansion in Gansu Province,which has great reference value for optimizing the urban system and optimizing the pattern of land development.
Gansu provinceUrbanizationNighttime light dataTemporal and spatial evolvementExpansion of cities
NETL
NSTL
万方数据
