Study On Spatial-temporal Changes Of Urban Built-up Areas In Fujian Province Based On Multi-source Data

Urbanization is the result of the development of Social Economy and Science &Technology,which is mainly manifested in the continuous expansion of urban spatial distribution and the increasing scale of urban land use.As an important indicator of urban development and change,urban built-up area is the basic information for people to understand the city.Many scholars began to study its space-time evolution,spatial pattern evolution and its driving forces.Fujian Province is an important starting point of the Marine Silk Road in the 21 st century and a necessary passageway for the North-South Passage of the West Bank of the Pacific.Taking Fujian Province as the research area was conducive to a correct understanding of the spatial and temporal evolution of urban expansion and its driving forces.It can provide some reference for the urban spatial layout planning and urban sustainable development policy of Fujian Province.In this paper,the characterization of urban spatial morphology on night-time lighting data was discussed,and the correction of different types of night-time lighting data from 1992 to 2017 were comprehensively considered.Based on the long time series night-time lighting data,MODIS and statistical data,the extraction index of built-up area was studied.Temperature Vegetation Light Built-up Area Index was applied to extract urban built-up areas in Fujian Province,and good results were achieved.Finally,the spatial pattern and evolution of urbanization in Fujian Province were studied by combining the annual average expansion rate and intensity,expansion direction,compactness index,expansion type index and expansion elasticity coefficient.The spatial variation and heterogeneity of urban built-up area expansion were found through spatial and temporal evolution,spatial morphology and coordination analysis.The results show that:(1)Temperature Vegetation Light Built-up Area Index has high precision and good feasibility in the extraction of urban built-up area in Fujian Province.It plays an important role in the extraction of urban built-up area in Fujian Province from 1992 to 2017 and the study of spatial pattern and evolution of urbanization in Fujian Province,which has certain scientific value.(2)In the process of urbanization in Fujian Province,the area ofbuilt-up areas increased from the slow growth stage in 1992-2002 to the rapid growth stage in 2002-2017.Overall,the growth trend of built-up areas has shown a polynomial model in the past 26 years.From 1992 to 2017,the compactness index of Fujian Province decreased continuously,and the spatial distribution of urban built-up areas changed from compact clusters to scattered patches.The compactness index of Fujian Province changed the most in 2007-2012 and the smallest in 2012-2017.During 1992-1997 and 2002-2007,Fujian Province was in the obvious expansion stage of built-up area,1997-2002 and2007-2012 were in the significant expansion stage of built-up area,and 2012-2017 was in the stage of population growth.(3)Through the analysis of the driving forces of the expansion of urban built-up areas in Fujian Province,it is found that the number of employees representing population growth and the consumption level of residents representing economic growth were the most important driving factors for the expansion of urban built-up areas in Fujian Province,and social productivity,science and technology education and industrial structure are the second driving factors.