Comparatively Studying On The Urban Sprawl Based On Bayesian Hierarchy In Two Metropolitan Areas,Yangtze River Delta And Central Plains

The paper investigated comparatively the spatiotemporal variation and influencing factors of the urban sprawl in two metropolitan areas,Yangtze River Delta and Central Plains.Based on the data of remote land use monitoring dataof 1990,1995,2005,2005,2010 and 2015 and socio-economic data,the author uses classical statistics and Bayesian statistical method to study the Temporal and Spatial Evolution of Citie of the two Urban Agglomeration.At present,although there are many researches on urban expansion,there are few studies on urban agglomerations,and there is little comparison between urban agglomerations.Most of them are based on classical statistics.Classical statistics are based on the large number theorem and the independent distribution.And the Bayesian statistical intergration comprehensive information,sample information and apriori information,the time and space process is decomposition into the overall time trend,the overall spatial distribution pattern and space-time interaction pattern,and Bayesian statistical not based on the large number theorem and independent distribution of the premise,it Makes the statistical results more scientific and reasonable.The result of two urban group about spatiao-temporal pattern has mainly four findings:Firstly,In the period of study,urban sprawl of two metropolitan areas presents increasing situation,during 2000-2005,the urban sprawl of two urban agglomeration were all up to the highest.The net area and rate of increase respectively2759km~2,36.6%and 441km~2,31.1%.The difference is rapid urban sprawl in Yangtze River Delta mainly occurred during 2000-2005,2005-2010 and 2010-2015,However,the rapid expansion of the Central Plains mainly occurred in the three stages,1990-1995,2005-2005,and2010-2015,from 2005 to 2010,the speed of urban expansion weaken..Secondly,The patternof space-time of two metropolitan areas presentssignificant difference.The urban expansion in Yangtze River Delta presented cycle mode,from the core Shanghai to the north and south.The centre circle mode appeared in the urban sprawling process in Central Plains.Besides during the four stages of urban expansion,urban sprawling hotspot areas were all emerged in two metropolitan areas,but the number of urban sprawling hotspot areas in Yangtze River Delta more than the Central Plains,And theurban sprawling hotspots areas moved during the different sprawling stage.The urban sprawl in YangtzeRiver Delta arise a spatial agglomeration phenomenon and significant spatial heterogeneity characteristics.On the contrary,the urban sprawl in Central Plains arise a significant spatial homogeneity characteristics.Thirdly,Theurban sprawlof two metropolitan areas presents different potential variation trend.The urban potential of expansion in Yangtze River Delta higher than Central Plains.The future trend of urban sprawling location in Zhejiang Province,and the urban structure of Yangtze River Delta maybe change in the future,the city construction in Central Plains may remain invariant.Using the geographical detectors,the spatial lag model and the Bayesian hierarchical regression model to study the influencing factors of the twourban agglomeration by studying,Two urban group influenced by the total economy,population size,income level,industrial structure,traffic accessibility and geographical conditions Mechanism,but the main influenceof two metropolitan areas presents difference.The two metropolitan areas were all influenced by economic factors,population scale,resident income,industrial structure,traffic and geography.The difference of the two urban agglomeration areas was that the main driving factor in Yangtze River Delta region was economic factor,but the population factor drove mainly the urban sprawl in Central Plains.development of economy enhance residents'income level,meanwhile,due to the development of economy,residents have higher requirements onliving environment,supporting facilities,and industry and the tertiary industry.and then drive urban sprawling,include residential,commercial and industrial land increased dramatically.The results proved that the conclusion of this paper.This paper analyzes the differences between the expansion of developed urban agglomerations and the development of urban agglomerations from the aspects of urban expansion mode,spatial and temporal characteristics of expansion,evolution and driving force.It is hoped that it will provide reference for the expansion of urban agglomerations in less developed regions such as CentralPlains urban agglomeration.Central Plains urban agglomeration may expand along the Yangtze river delta urban agglomeration path.The Yangtze river delta urban agglomeration may be the advanced form of the urban expansion of the Central Plains urban agglomeration.Therefore,in the process of the future development,the synergies of the mature urban agglomeration can be fully utilized by optimizing the function of the mature urban agglomeration.TheCentral Plains urban agglomeration follows the theory of regional development in the late development,takes economic development as the mainstay,breaks through the development mode of single center,develops the multi-center urban area gradually,develops to the higher level city with the development of multi-center combined radiation urban agglomeration Group expansion stage,to promote the rapid rise of the Central Plains urban agglomeration,and to achieve sustainable development goals.