Identification And Spatial Analysis Of Urban Fringe Area Based On POI

China's urbanization process is also advancing at an unprecedented speed.Under the background of rapid urbanization,urban fringe area,as a transitional area of urban and rural spatial integration,is the frontier of urban expansion.In the process of expansion and spread of urban spatial scale,the areas with the fastest change of land use pattern and the most drastic change of spatial structure are located in the urban fringe.The rapid and disorderly expansion of urban fringe will lead to a series of social,economic and environmental problems,such as environmental pollution,inefficient land use,loss of arable land and so on.It is urgent to implement scientific and rational planning and management of urban fringe.Scientifically and accurately delimiting the spatial scope of urban fringe is the precondition of planning and management,and is of great significance for ensuring the health and sustainable development of the city.Taking Guangzhou-Foshan metropolitan area as the research object,this paper attempts to apply urban POI data to the identification of the spatial range of urban fringe,focusing on four aspects: the concept analysis and application research of urban fringe,the identification and delimitation of the spatial range of urban fringe,the land use evolution of urban fringe,the expansion pattern of urban fringe and its influencing factors.The main conclusions are as follows:(1)Based on POI data,it is an effective method to identify and delimit urban fringe area by using fracture point analysis method and density-distance analysis method.Based on urban POI data and remote sensing data,this study quantitatively identifies and delimits the spatial range of urban fringe in Guangzhou-Foshan metropolitan area by using kernel density estimation,fracture point analysis and density-distance analysis,and uses remote sensing image location verification and land use structure information entropy model to carry out the research results.The test preliminarily confirms the scientificalness and rationality of the method of using urban POI to identify and delimit urban fringe areas in this study.(2)Guangzhou-Foshan urban fringe distributes around highly urbanized urban core areas and sub-urban centers in a concentric circle.Guangzhou-Foshan's urban fringe area is 2154.88 km2,accounting for 19.18% of the total area of Guangzhou-Foshan metropolitan area,covering Panyu,southern Huangpu,Eastern Baiyun,southwestern Zengcheng,central and southern Huadu,as well as parts of Foshan Nanhai and Shunde,as well as the areas surrounding the sub-centers of Zengcheng,Conghua,Huadu,Sanshui,Gaoming and Shunde.At that time,the urban fringe area was affected by many factors,and its shape was irregular circle with different widths.The land use types in the urban fringe area were diverse,and all kinds of land types were interlaced,mainly for construction land,cultivated land,forest land and lake wetland.(3)In the process of transition from non-urban fringe to urban fringe,the overall landscape fragmentation declines and the scale of construction land continues to grow.Specifically,the scale and area of construction land are increasing,mainly converting other types of land use into construction land;cultivated land,forest land and lake wetland are encroached and cut by construction land,and their scale is declining,showing fragmentation distribution.Meanwhile,the overall landscape fragmentation degree of land use decreases year by year,and the overall spatial shape of land use types gradually tends to be simple and regular.The degree of landscape patch agglomeration and integration between patches are improved,and the structure of land use types tends to be simple.(4)The expansion of Guangzhou-Foshan's urban fringe is influenced by many factors,such as physical geography,road traffic,planning policy and the level of urban economic development.Natural geographical factors play a restrictive role in the expansion of urban fringe areas.Road traffic can effectively accelerate the development of urban fringe areas,but the fundamental driving force for its development and expansion comes from the development of urban economy.Policy guidance such as planning can guide the orderly development of urban fringe areas through macro-control.The spatial expansion mode of urban fringe is mainly guided by traffic,residential land development,industrial park development and university city construction.