Multiscale Analysis On The Spatiotemporal Evolution Characteristics Of Population Distribution Of Urban Agglomeration In The Middle Reach Of Yangtze River

Population distribution is a spatial form of population process.Study on the pattern and evolution of population distribution as the core research contents of the population problem is significant in theory and practice,and that a well-balanced population distribution is the foundation of an orderly society.Nowadays,urban agglomeration has increasingly become the important carrier of population agglomeration and urbanization development in China.With the proposed Yangtze Economic Belt strategy and development plan of urban agglomeration in the middle reaches of Yangtze river in 2015,construction of the area rises for the national development strategy and catches more and more attention.Based on this background,by using the 2000 and 2010 census data of Hunan,Hubei and Jiangxi,we analyzed the distribution and its changes of population in urban agglomeration in the middle reaches of Yangtze river under multiscale since 2000,from the aspects of population density,urbanization and aging.Results are briefly shown as follows:(1)In 2000-2010,the population distribution of urban agglomeration in the middle reaches of Yangtze river presents an increasingly trend of ‘multi-core' structure.On the scale of prefecture level city,the spatial pattern of population density has experienced a shift from single core to multicore spatial pattern.Moreover,the population density distribution characteristic of ‘multi-core' structure is more remarkable under the county scale analysis,and it formed a ‘ring' type distribution pattern around the green heart of urban agglomeration in the middle reaches of Yangtze river and China.(2)Increase of population in towns mainly contributes to the increase of urban population,therefore the population urbanization has realized a rapid development.The areas of high level of urbanization have shifted from distributing in the north of Yangtze River to distributing along the Yangtze River,Beijing-Kowloon and Zhe-Gan Railway.And the multicore spatial pattern of urbanization has been formed.Analysis of urbanization pattern under the scale of county indicates that the county urbanization was lack of development.The areas of high level of urbanization are mostly distributed in the city centers and their surrounding areas which have a high level of economic development,well-developed transportation and perfect infrastructure.(3)At the same time of experienced a rapid development of urbanization,urban agglomeration in the middle reach of Yangtze river development is faced with the serious aging problem.Analysis on the scale of prefecture level city shows that all cities have entered a different degree of aging state besides Jing Dezhen and Ji'an.And there presents a more remarkable evolution pattern of population aging distribution under the scale of county than it under the scale of prefecture level city.The level of population aging shifts from high to low from West to East.(4)since 2000,in the middle reaches of Yangtze river,the total population grows continuously,but the pace has slowed down.The population distribution is unbalanced,which shows a concentrating in Wuhan,Changsha and Nanchang.The population agglomeration and urbanization level of these central cities is increasing,but the level of whole urban agglomeration in the middle reach of Yangtze river is low.The gravity centers of total population and urban population are shifting southwards while the elder population gravity center is shifting northwards.Spatial autocorrelation analysis of population density,urbanization and aging further reveals the differences and changes of population distribution of urban agglomeration in the middle reach of Yangtze river.