Analysis On The Expansion And Driving Force Of Built-Up Areas In Zhengzhou Metropolitan Area From 1990 To 2018

In recent years,the process of urbanization has been accelerating,and the urban civilization and the quality of human life have been improving.However,a series of social and economic problems caused by the disorderly expansion of cities have become increasingly prominent.It is very important to timely understand the spatial and temporal pattern,spatial form and driving factors of urban expansion to achieve urban physical growth and regional sustainable development.With the rise of central China and the development planning of Central Plains urban agglomeration,Zhengzhou metropolitan area has become the core area of Central Plains urban agglomeration,and its development and construction speed and scale are expanding.Therefore,rapid and effective monitoring and analysis of the expansion of Zhengzhou metropolitan area,and in-depth exploration of the dynamic evolution process and expansion driving force of Zhengzhou metropolitan area are of great significance to the rational planning of the efficient development of Zhengzhou metropolitan area.This paper take Zhengzhou metropolitan area as the research object,based on the existing urban built-up area datasets,after comparison,analysis,evaluation and optimization,the Zhengzhou metropolitan built-up area is obtained.Multiple spatial expansion indicators are used to quantitatively analyze the spatial characteristics,expansion scale,expansion form and land scale of the built-up area expansion,and the driving force of the built-up area expansion is analyzed by using the grey correlation degree.The main conclusions of this paper are as follows:(1)The scope of the built-up area of Zhengzhou metropolitan area is determined.Based on the existing urban built-up area data and the actual situation of Zhengzhou metropolitan area,the time series length and spatial resolution of the built-up area data are compared and analyzed,and the global urban boundaries(GUB)data products,China’s land use/cover dataset urban(CLUD-Urban)data products and standardized urban build up area dataset for China(SUBAD-China)data products are preliminarily screened,The accuracy of three sets of built-up area products is evaluated,and the accuracy of GUB products is the best.Then the GUB products are optimized to obtain the final built-up area of Zhengzhou metropolitan area.(2)The temporal and spatial variation law of the built-up area in Zhengzhou metropolitan area is revealed.(1)In terms of spatial expansion scale: from 1990 to 2018,the expansion speed of the built-up area in Zhengzhou metropolitan area showed an increasing trend,in a state of low-speed expansion,and the expansion intensity was relatively stable,the expansion intensity value was small,and the area of the built-up area accounted for a relatively small proportion of the total urban land area.(2)In terms of spatial expansion form: from 1990 to 2018,the compactness index of the built-up area of Zhengzhou metropolitan area showed an upward trend,and the fractal dimension showed a downward trend.The built-up area was in a state of filling and expansion,and the center of gravity of the built-up area of Zhengzhou metropolitan area moved 3104 m to the southeast.(3)In terms of the land scale of urban built-up areas,Zhengzhou metropolitan area ranks first in the medium distribution,and the Jiefu index |α| the value is between 0.764 and 0.851,and the Gini coefficient is between 0.251 and 0.468.The development of small and medium-sized cities in the region is relatively balanced.(3)The driving force of the expansion of the built-up area in Zhengzhou metropolitan area is clarified.Natural environmental factors,policy factors and socio-economic factors are important driving forces for urban expansion.Among them,terrain and water system in natural environmental factors play a key role in urban expansion;Among the policy factors,the outline of the overall development planning of the Central Plains urban agglomeration and the strategic planning of the national economic and social development of Henan Province have a great impact on the expansion of Zhengzhou metropolitan area;Among the socio-economic factors,the total urban population,regional GDP and total retail sales of social consumer goods are highly correlated with the expansion of the built-up area,and the correlation coefficient is above 0.74.Therefore,economic development,population growth and total retail sales of social consumer goods play a major role in the expansion of the built-up area.