Research On Urban Space Expansion Of Lanzhou City Based On DMSP/OLS Data(1993-2013)

Modern cities are based on a certain geographical location and natural resources,with the productivity level of the social development stage as the source of power,to accommodate the urban system of the city as the basic unit,and to express the highest ambition of human civilization.The real vision of realizing the material pursuit and spiritual aspiration of mankind is the goal of action,to create a material space entity that dynamically evolves the process of human and human social development by creating a plurality of complex elements that conform to the consciousness of human perception of space.From the perspective of social development,the city is the product of the social builder or the product of the social developer.It is the result of the birth of social production and a spatial attribute of carrying social activities.Under the background of the global integration process and the new national urbanization strategy,exploring the sustainable and flexible urban space expansion has become a popular research object of many scholars.Through the analysis and research of urban spatial expansion,we can grasp the characteristics and laws of urban spatial change.Urban science development provides decision-making basis.According to statistics,China's urbanization rate has basically reached the global level of urbanization at the end of 2013,indicating that China has basically entered urban-style society.This study firstly used the DMSP/OLS nighttime lighting data to easily obtain the spatial space of the city with long-lasting light source image information and the advantages of responding to the large-scale spatial pattern.The research was carried out in Lanzhou City,Gansu Province,in 1993,1997 and 2001.The DMSP/OLS nighttime lighting data of Lanzhou City in 2005,2009 and 2013 and the relevant city information data of Lanzhou City in the China Urban Statistical Yearbook(1994-2014)are the original data of research,and the research tools of ArcGIS10.2 are used.The city space information of Lanzhou City was extracted by reference comparison method.Secondly,the study of urban space expansion scale by calculating expansion speed,expansion dynamics,expansion intensity,expansion coordination index and dispersion coefficient;urban spatial expansion trend through DMSP/OLS image grid map and calculation of urban spatial center of gravity The study of urban spatial expansion by calculating fractal dimension,compactness and coefficient of variation;using IBM SPSS Statistics 23 as a technical tool,using principal component and multiple regression analysis as the research method to study the driving force of urban spatial expansion.Finally,based on the results of the above four points and the "China Lanzhou 2030 City Planning Vision" compiled by Lanzhou Urban and Rural Planning and Design Institute,the following four aspects of development strategies and prospects are proposed,that is,breaking the administrative boundary and realizing the common strategy of the city.Plan the vision,promote the sustainable use of mixed land to shape a compact urban space,integrate flexible planning into urban planning to address climate risks,and coordinate diversified drivers to respond to the vision of urban strategic planning.In order to provide a positive reference for the future urban space expansion and construction of Lanzhou City.