Research On Urban Land Spread Measure And Regulation In Mid-southern Liaoning Urban Agglomerations

The spread of urban land has caused a series of urban problems such as loss of cultivated land resources,environmental pollution and traffic congestion.Therefore,effectively controlling the spread of urban land has become the key to sustainable urban development.As one of the nine regional urban agglomerations,the urban agglomeration in central and southern Liaoning Province has a per capita construction land area of 112.57 m2 in recent ten years,which is 13.26 m2 higher than the national average level.The urban land expansion is significant.Therefore,in order to enhance the intensity of urban land use and realize the sustainable and coordinated development of cities and urban agglomerations in central and southern Liaoning,it is necessary to regulate the spread of urban land and guide the rational expansion of urban land.Existing studies on the measurement and regulation of urban land use spread mostly focus on single metropolis or economically developed areas with the same characteristics,while a few focus on cities within urban agglomerations,but always take individual cities as the starting point,ignoring the dominant position of urban agglomerations in development.In the measurement method,index method,graph analysis method and model method are used to measure the relationship between human and land,spatial characteristics and other aspects,so as to ensure the comprehensiveness of the measurement.In terms of influencing factors,theoretical experience analysis and empirical analysis are mainly used.Through the Logistic model and multivariate regression equation model,the driving force of urban land use spread is analyzed,and the factors of urban land use inhibition are less explored.In terms of regulation perspectives and strategies,with the city's smart growth as the main theoretical basis,the macro-level adopts the rigid urban development policy,the economic guidance policy and the infrastructure guidance policy supplemented by the policy tools,lacking micro-perspective differential control measures.Based on the idea of "spread measurement-analysis factor-exploration strategy",this study aims to control the spread of urban land and promote the rational growth of the city.Based on the theory of urban growth,first of all,the natural,social and economic development of the urban agglomerations in central and southern Liaoning.And in-depth analysis of the current situation of urban land use scale,structure,and efficiency,and comprehensively understand the land use status of urban agglomerations in central and southern Liaoning:Secondly,according to the theory of man-land relationship,based on the connotation of urban land use spread and the premise of fixed land area per capita consumption,the urban land spread index is constructed according to the dynamic single index of "population-land".The degree and type of urban land spread in different time periods are determined,and the urban agglomeration and urban land use are analyzed.Spatial and temporal evolution characteristics of spread;Thirdly,the influencing factors of urban land use spread in central and southern Liaoning urban agglomeration are excavated from both theoretical and empirical aspects.Based on theoretical analysis,the model factors are determined by multiple collinearity test and stepwise regression.The process,direction and effect of each factor on different types of urban land use spread are analyzed by two-stage least square method;Finally,taking the factors(industrial structure,urban land use structure and urban land use intensity)that restrain the spread of urban land as the breakthrough point,through the analysis of the current situation,characteristics and rationality of industrial structure,urban land use structure and urban land use intensity,putting forward the strategies of industrial structure,urban land use structure and urban land use intensity,in order to control the spread of urban land use.The study can provide a path for urban land spread control in the central and southern Liaoning urban agglomeration,and provide a reference for regional planning and development direction of urban agglomeration.Conclusions:(1)The urbanization development level of the central and southern Liaoning urban agglomerations is uneven.The scale of urban scale is relatively complete,but the structure is slightly out of balance.The scale of small and medium-sized cities is insufficient and the first distribution of cities is not obvious.Industrial division of labor is blurred,coordination is not high,and the contribution rate of the secondary industry is as high as 46%.The speed,magnitude,dynamics and intensity of urban land expansion have changed from "first rise and then fall".The absolute expansion rate and relative expansion rate of urban land use have begun to slow down,but the depth of expansion has intensified,and land use patterns have begun to shift to internal tapping potential.(2)The growth of urban land use can be divided into five types:type I to V,of which type I and III belong to urban land spread,and the rest are reasonable growth types of urban land.In terms of time series evolution,urban land use spread in the central and southern Liaoning urban agglomeration mainly depends on land-driven construction.The growth rate of regional land use is always higher than the population growth rate.The main type of urban land spread is type I,and the degree of urban land spread is gradually weakening.In terms of spatial evolution,severe land-use sprawl cities have shifted from core cities to second-and third-tier cities.The spatial form has undergone the evolution of "single-core semi-circular","ouble-core strip","multipoint blooming".The gap of urban sprawl degree has been narrowed.(3)Urban land use sprawl is the result of multiple factors.The scale of urban population,economic growth and disposable income of residents have different effects on the promotion of urban land use spread in the first,third and overall categories of urban agglomerations in central and southern Liaoning Province.Among them,the scale of urban population is the primary factor to promote the urban land spread in the whole and the first categories of Urban Agglomerations in central and southern Liaoning Province,while the disposable income of residents is the driving factor.The first factor of urban land use spread in the third category of urban agglomeration in central and southern Liaoning Province is economic growth,which promotes the urban land spread weakest.The quality of economic growth and the adjustment of industrial structure have a controlling effect on the urban land spread in the first,third and overall categories of urban agglomeration in central and southern Liaoning Province,and the quality of economic growth mainly inhibits the urban land spread through the path of technological progress,while the impact of technological efficiency on the urban land spread is not significant.(4)In terms of industrial restructuring,the primary industry,with Liaoyang,Panjin and Tieling as the main developing cities,focuses on optimizing the industrial layout,enhancing the industrial spatial location effect and industrial structure effect,realizing the standardization of agricultural production mode through agricultural technology reform and innovation,and establishing high-end agricultural production bases to develop modern agriculture.Improving the spatial competitiveness of agriculture;Secondary industry should accelerate the transformation and upgrading of industrial structure,improve the effect of industrial structure,integrate traditional industry with emerging industry,and enhance the spatial competitiveness of secondary industry.The tertiary industry will further clarify the division of urban functions and specialization,enhance the radiation driving capacity of producer services,promote the deep integration,matching and guarantee of producer services and the first and second industries,and promote the development of producer services to a higher level.(5)In terms of urban land structure adjustment,the investment redundancy of residential land,industrial land and road general land in the urban agglomeration of central and southern Liaoning is obvious.In 2015,the urban agglomeration of central and southern Liaoning needs to reduce residential land by 9.903 km2,industrial land by 14.065 km2,road general land by 7.328 km2,municipal public facilities land by 0.409 km2 and green land by 0.174 km2.Investment in fixed assets can be reduced by 22.093.6 billion yuan without affecting output.In addition,according to the redundancy adjustment of various types of urban land input,the reasonable land use structure scope of various types of urban land can be obtained.Taking Dalian as an example,residential land 27%-34%,public facilities land 10%-14%,industrial land 22%-27%,storage land 2%-5%,road general land 13%-20%,and municipal public facilities land 2%3%.Green space 8%-12%.(6)As for the adj ustment of urban land use intensity,the urban land use intensity of the central and southern urban agglomeration in Liaoning Province has always remained within the range of medium intensity,and shows a general fluctuating downward trend.Urban land has great potential to tap.Among them,the absolute potential of scale is 757.06-946.32 km2,and the relative potential of scale is 64-80%.In order to improve the intensity of land use,adjustment strategies such as revitalizing the stock of construction land,improving land engineering technology and rational development and utilization of underground space are put forward.