Research On The Urban Sprawl In Transitional China:Multi-Scale Measurement,Mechanism,and Remedies

Since the economic reform and opening up,China has experienced a series of institutional transformation,such as globalization,the decentralization of the central government to the local authorities,the transformation of a planned system to a market economy,and the rapid development of urbanization.The sprawl of industrial land and residential land,characterized by low density,leapfrog and functional scattered,causes a series of urban problems,such as the loss of cultivated land resources,environmental pollution and ecological destruction.Therefore,how to control the urban sprawl has been one of most challenging task facing city governments.However,China has not yet formed a theoretical framework that is suitable for its transitional period,as well as practically guiding urban planning and urban management.Therefore,in the transition period of decentralization,marketization,globalization and urbanization,it is necessary theoretically and practically to explore the measure,internal mechanism and control strategy of urban sprawl in China.This paper consists of following three aspects:Firstly,the multi-dimensional and multi-scale connotation theory and measurement of urban sprawl is put forward.An empirical research of measuring urban sprawl based on the the multi-dimensional and multi-scale measuring framework,is further conducted on city scale and street scale,respectively.Secondly,the explanation of the inherent mechanism of urban sprawl in transitional China is constructed,with an analysis of the roles of Chinese government and market.Through the method of building logistic regression models,the determinants of industrial land sprawl and residential land sprawl are investigated,to offer empirical evidence to verify whether government and market factors have an impact on urban sprawl and how it will affect.Thirdly,the logics of the behavior choice of the government and market in the urban growth management are analyzed.and a multitarget monitoring system is further built up.The conclusions are as follows.(1)Urban sprawl in large cities has become more prominent across China.The expansion rate of built-up areas is significantly faster than the population growth rate.Many cities display as a "polycentric" pattern,but most in its early stages.The sub-centers are dominated by leaping development,with low population density and poor accessibility to urban infrastructure.Moreover,the regional difference of the distribution of urban sprawl is distinct.The eastern coastal cities in China are always characterized by rapid economic development,dense population and intense land development,which results in their high scores in the morphological dimension,and low scores in the density and efficiency dimensions.Whereas,due to the relatively lagging economic development and disperse population,the middle and western cities ranked more sprawled in the density and efficiency dimensions,and ranked less sprawled in the morphological dimension.In addition,the morphological dimension is extensively affected by their physical geographical conditions.(2)Urban sprawl is dominated by leapfrog development of industrial land and residential land,and the main space carriers for urban sprawl are development zones,high-education parks,and new towns.These types of suburban development show obvious characteristics of leapfrog,low density,single functional structure,and poor accessibility of urban services and transits.Development zones with better conditions have gradually stepped forward to undertaking more urban functions with better infrastructure and facilities,as well as more dense population.(3)Under the transitional processes of decentralization,marketization,globalization and urbanization,the participants in Chinese urban development are becoming more and more diverse,and the behavior choice of these agents constitutes the fundamental driving force for urban sprawl.The entrepreneurial city governments adopt proactive policies to promote economic growth and urbanization,via large-scale land acquisition and building new towns/sub-city,development zones,and higher education parks guided by planning policies.Driven by the maximization of interests,real estate developers contribute to the rapid expansion of residential land.Different types of industrial enterprises influence the suburban industrial land development in different ways.The residents' demand preference for suburban housing result in various forms of real estate projects in suburbs,such as villas,high-end residential communities,"small property right house",etc.(4)The driving mechanism differs between industrial land sprawl and residential land sprawl.The empirical studies verified that the dominant forces of industrial land sprawl are planning policies and the establishment of development zones.Local governments promote industrial suburbanization through the establishment of development zones and proactive planning policies.The factors of market mechanism such as land price,traffic accessibility and labor force play a secondary role in the process of industrial land sprawl.Furthermore,the government participates in market operations by using the logic of the market.For example,the price of industrial land is artificially depressed to attract industrial investment,which promotes the industrial land sprawl in suburbs.On the contrary,both government and market forces play very important roles in the process of residential land sprawl.Besides the planning policy,accessibility to transportation and urban service is also a major factor driving residential land development.Especially,the impact of kindergarten,primary and secondary education facilities is very significant.(5)The failure of policies for containing urban sprawl should be imputed to the game of interests between the central government and local governments.At present,a series of policies,such as urban planning,basic farmland protection land annual land use plan,have not played their due role in curbing urban sprawl and protecting cultivated land.Local governments aiming for economic development and urban growth have conflicts of interest with the central government whose goal is to prevent urban growth and protect cultivated land.Local governments are motivated to break through the land quotas and modify plans to meet the needs of the construction projects.At present,the challenges are how to coordinate the conflicts of interests in urban growth management by deepening reform,and how to transform the monocentric management mode into a polycentric governance mode.A multi-oriented urban sprawl controlling strategy is a possible way to address these problems and challenges.