The emergence of rapid transit,primarily represented by high-speed railway(HSR),while reshaping the regional traffic patterns,leads to the reconstruction and redistribution of population and industry.This leads to eit...The emergence of rapid transit,primarily represented by high-speed railway(HSR),while reshaping the regional traffic patterns,leads to the reconstruction and redistribution of population and industry.This leads to either shrinkage or expansion of urban scale.However,research on the influence mechanisms of the urban scale has mostly concentrated on historical,economic and social factors.The influence of traffic factors is rarely mentioned in current research.Therefore,this study examines Northeast China,where the change in urban scale is most significant,to discuss the spatial impact of high-speed railway on the urban scale.This is of great significance in terms of enriching current understanding of the factors affecting the urban scale.The results included the following:1)The high-speed railway produced considerable space-time convergence effects,however,simultaneously aggravated the imbalance in traffic development in Northeast China.The increase in accessibility presents attenuation characteristics from the high-speed railway.Additionally,the high-speed railway has changed the mode of cooperation between cities in the provinces,inter-regional and inter-provincial cooperation models gradually become popular.2)The change rate of accessibility and the urban scale present significant spatial coupling phenomena,with the change rate of the Harbin-Dalian trunk lines and its surroundings being more significant.3)There are predominantly four modes of the influence of high-speed railway on the urban scale,which make difference city present expansion or shrinkage.展开更多
The adjustment of administrative divisions is one of the important factors guiding China's urbanization, which has profound economic and social effects for regional development. In this paper, we comprehensively d...The adjustment of administrative divisions is one of the important factors guiding China's urbanization, which has profound economic and social effects for regional development. In this paper, we comprehensively describe the process of the adjustment of administrative divisions at provincial and municipal levels in China and summarize the effects on the basic structure and patterns of the spatial development. We quantitatively assess the effects on fields such as urbanization and social economy through the use of multidimensional scaling. The results show that: 1) Upgrading county to municipality(or city-governed district) is the main way of adjusting the administrative divisions. It is also an important factor in the spatial differentiation of interprovincial urbanization. China's population urbanization can be divided into four patterns including interprovincial migration, provincial migration, natural growth, and growth caused by the adjustment of administrative divisions, which is also the main reason for the increased Chinese urbanization rate at the provincial level. 2) Taking the city of Beijing as an example, we generalize five adjustment patterns made to administrative divisions: the set-up of sub-districts, the set-up of regional offices, the upgrading of townships to sub-districts, the upgrading of townships to towns, and the set-up of towns and the addition of new regional offices. We summarize the municipal urban spatial structure, including the sub-district office area in the central urban area, the regional office area in the new urban area, the mixed area of villages, towns, and sub-district offices in the suburb area, and the township area in the outer suburb area. 3) The adjustment of administrative divisions triggers a significant circulative accumulation effect, resulting in the spatial locking of population and industrial agglomeration. It affects the evolution of the urban spatial form and plays an important role in shaping the urban spatial structure to move to the characteristic of multicenter. In general, the adjustment of administrative divisions was an important factor affecting the inflated statistical level of urbanization and also an important driving force for the evolution of Chinese urban spatial organization structure.展开更多
Considering the urban characteristics, a customized multi-scale numerical modeling system is established to simulate the urban meteorological environment. The system mainly involves three spatial scales: the urban sca...Considering the urban characteristics, a customized multi-scale numerical modeling system is established to simulate the urban meteorological environment. The system mainly involves three spatial scales: the urban scale, urban sub-domain scale, and single to few buildings scale. In it, different underlying surface types are employed, the building drag factor is used to replace its roughness in the influence on the urban wind field, the effects of building distribution, azimuth and screening of shortwave radiation are added, and the influence of anthropogenic heating is also taken into account. All the numerical tests indicate that the simulated results are reasonably in agreement with the observational data, so the system can be used to simulate the urban meteorological environment. Making use of it, the characteristics of the meteorological environment from the urban to urban sub-domain scales, even the among-buildings scale, can be recognized. As long as the urban planning scheme is given, the corresponding simulated results can be obtained so as to meet the need of optimizing urban planning.展开更多
Based on urban physical space and theory of landscape ecology,a triune assessment framework—‘size-densitymorphology’—was constructed in order to analyze the spatial pattern and the scale effect of urban resilience...Based on urban physical space and theory of landscape ecology,a triune assessment framework—‘size-densitymorphology’—was constructed in order to analyze the spatial pattern and the scale effect of urban resilience in Shenyang of China in 2015,and to explore the main impact factors of landscape under different spatial scale backgrounds.The results show that:1)Urban resilience is an optimal combination of the resilience of size,density,and morphology.The urban resilience of Shenyang displays scale effect;the overall resilience level increases with the increase in scale,while the spatial difference and spatial similarity tend to decrease resilience.2)As 2 km,1 km and 2 km are scale inflection points of average value curves for size resilience,density resilience and morphology resilience,respectively in an urban setting;the optimal scale unit of comprehensive resilience is 1 km.Choosing 1 km–2 km as the basic spatial scale better depicts overall pattern and detailed characteristics of resilience in Shenyang.The spatial amplitudes of 0.5 km and 1 km are sensitive points for spatial autocorrelation of morphology and density resilience,size,and comprehensive resilience to scale effect.3)The major landscape factors of urban size and morphology resilience transform with scale expansion.Aggregation index(AI)has a significant impact on urban resilience at different scales;its influence increases significantly with the increase in scale.4)The high-level area of comprehensive resilience in Shenyang is the eastern ecological corridor area,while the low value area is the peripheral extension area of the city.To promote the overall level of resilience in Shenyang,this paper argues that the construction of ecological infrastructure should be strengthened in the peripheral extension area in a balanced manner.In the city center,population and building density should be controlled;the intensity of human activities should be reduced;impetus should be placed on landscape heterogeneity;and the homogeneous expansion of the area of construction should be prevented.In the eastern ecological corridors,the exploitation of ecosystem lands should be strictly controlled,and the integrity of the green landscape patches should be maintained.展开更多
The Regional Atmospheric Modeling System (RAMS) and the computational fluid dynamics (CFD) codes known as FLUENT are combinatorially applied in a multi-scale numerical simulation of the urban surface layer (USL)...The Regional Atmospheric Modeling System (RAMS) and the computational fluid dynamics (CFD) codes known as FLUENT are combinatorially applied in a multi-scale numerical simulation of the urban surface layer (USL). RAMS and FLUENT are combined as a multi-scale numerical modeling system, in which the RAMS simulated data are delivered to the computational model for FLUENT simulation in an offline way. Numerical simulations are performed to present and preliminarily validate the capability of the multi-scale modeling system, and the results show that the modeling system can reasonably provide information on the meteorological elements in an urban area from the urban scale to the city-block scale, especially the details of the turbulent flows within the USL.展开更多
Scale is the range or measurement unit of the characteristics of natural or human ontology in the temporal or spatial dimension and is widely used in daily life and the study of various disciplines.Scale effect pertai...Scale is the range or measurement unit of the characteristics of natural or human ontology in the temporal or spatial dimension and is widely used in daily life and the study of various disciplines.Scale effect pertains to certain laws and characteristics that can only be reflected on a specific scale,so choosing the appropriate scale remains the basic premise of scientific research.The concept of the urban spatial system is complex and has the characteristics of scale dependence,and the selection of an appropriate spatial scale is important for the accurate estimation and description of urban issues.In this paper,we discuss spatial scale in urban research using cases that primarily come from the Chinese experience,provide some examples that demonstrate the importance of appropriate scale in urban research,including urban shrinkage,and highlight problems in spatial research.Ultimately,we suggest that scale consciousness should be the basic consciousness required in empirical research.展开更多
The intensified conflict between island urbanization and lagging supervision deserves special attention worldwide.Zhoushan Island has been an outstanding center of marine economic development in China but also one of ...The intensified conflict between island urbanization and lagging supervision deserves special attention worldwide.Zhoushan Island has been an outstanding center of marine economic development in China but also one of the areas most threatened by recent human activities.To cope with this challenge,the development of a retrospective understanding of the spatiotemporal dynamics of island urban growth is a key prerequisite.Detailed,multi-scales,long-term studies on island urban expansion are relatively rare.Remote sensing data,landscape metrics,and spatial statistics were used to characterize the urban landscape changes during the years from 1980 to 2013.Then,the potential determinants of island urban expansion were analyzed by integrating socioeconomic drivers,population factors,topographic variables,and policy guidance.The results indicate that Zhoushan Island has experienced a considerable urban expansion with an evident acceleration during the last period.Landscape changes in response to urban expansion varied with time,region,and scale.A general understanding of landscape metrics failed to reveal accurate dynamics for the urban landscape at a local level.At a block size of1 km,the urban landscape was more compact around the island urban center and the new developing zone,in contrast to the extensive and scattered pattern present across the entire region.Urban land primarily expanded from the urban center to the coastal regions due to topographic constraints and support from policy and economic benefits.The potential impact of the population factor decreased with urban growth,a finding that differs from several previous studies.The island urban dynamics observed in this study involved characteristics and differences that will guide future planning decisions and will provide a scientific case for urban development and sustainability with respect to islands and coastal regions in China.展开更多
This paper is to examine the urban and rural construction land data of Dafang between basic year and final year based on country scale and spatial econometrics,and analyze its spatial pattern and change feature. Accor...This paper is to examine the urban and rural construction land data of Dafang between basic year and final year based on country scale and spatial econometrics,and analyze its spatial pattern and change feature. According to the results,the construction lands in all the villages of Dafang County showed strong spatial autocorrelation and significant spatial cluster. After the analysis of local Moran's I,the construction lands in 381 villages of 36 counties presented strong activity. The original small-scale villages were gradually enlarging,which will not only gradually benefit local development,but also be in accordance with the strategy of " one city,one district,eight parks".展开更多
Urban rail transit(URT) has been playing an important role in urban sustainable development with its advantages of high speed,large capacity,high efficiency and low pollution.Estimating URT network scale is the key to...Urban rail transit(URT) has been playing an important role in urban sustainable development with its advantages of high speed,large capacity,high efficiency and low pollution.Estimating URT network scale is the key to ensure the scientificity and feasibility of its construction.The existing studies on rational scale of URT network have not dealt with the interaction of supply and demand.This paper describes the establishment of a system dynamics model of rational URT network scale determination,considering the interaction between URT construction and city social economic development as well as the dynamic equilibrium of capital supply and traffic demand,and the verification of the model validity by applying it to the case of Wuhan City's URT construction.展开更多
基金Under the auspices of National Natural Science Foundation of China(No.41471133,41871112).
文摘The emergence of rapid transit,primarily represented by high-speed railway(HSR),while reshaping the regional traffic patterns,leads to the reconstruction and redistribution of population and industry.This leads to either shrinkage or expansion of urban scale.However,research on the influence mechanisms of the urban scale has mostly concentrated on historical,economic and social factors.The influence of traffic factors is rarely mentioned in current research.Therefore,this study examines Northeast China,where the change in urban scale is most significant,to discuss the spatial impact of high-speed railway on the urban scale.This is of great significance in terms of enriching current understanding of the factors affecting the urban scale.The results included the following:1)The high-speed railway produced considerable space-time convergence effects,however,simultaneously aggravated the imbalance in traffic development in Northeast China.The increase in accessibility presents attenuation characteristics from the high-speed railway.Additionally,the high-speed railway has changed the mode of cooperation between cities in the provinces,inter-regional and inter-provincial cooperation models gradually become popular.2)The change rate of accessibility and the urban scale present significant spatial coupling phenomena,with the change rate of the Harbin-Dalian trunk lines and its surroundings being more significant.3)There are predominantly four modes of the influence of high-speed railway on the urban scale,which make difference city present expansion or shrinkage.
基金Under the auspices of National Natural Science Foundation of China(No.41701164,71433008)Programme of Excellent Young Scientists of the Institute of Geographic Science and Natural Resources Research,Chinese Academy of Science
文摘The adjustment of administrative divisions is one of the important factors guiding China's urbanization, which has profound economic and social effects for regional development. In this paper, we comprehensively describe the process of the adjustment of administrative divisions at provincial and municipal levels in China and summarize the effects on the basic structure and patterns of the spatial development. We quantitatively assess the effects on fields such as urbanization and social economy through the use of multidimensional scaling. The results show that: 1) Upgrading county to municipality(or city-governed district) is the main way of adjusting the administrative divisions. It is also an important factor in the spatial differentiation of interprovincial urbanization. China's population urbanization can be divided into four patterns including interprovincial migration, provincial migration, natural growth, and growth caused by the adjustment of administrative divisions, which is also the main reason for the increased Chinese urbanization rate at the provincial level. 2) Taking the city of Beijing as an example, we generalize five adjustment patterns made to administrative divisions: the set-up of sub-districts, the set-up of regional offices, the upgrading of townships to sub-districts, the upgrading of townships to towns, and the set-up of towns and the addition of new regional offices. We summarize the municipal urban spatial structure, including the sub-district office area in the central urban area, the regional office area in the new urban area, the mixed area of villages, towns, and sub-district offices in the suburb area, and the township area in the outer suburb area. 3) The adjustment of administrative divisions triggers a significant circulative accumulation effect, resulting in the spatial locking of population and industrial agglomeration. It affects the evolution of the urban spatial form and plays an important role in shaping the urban spatial structure to move to the characteristic of multicenter. In general, the adjustment of administrative divisions was an important factor affecting the inflated statistical level of urbanization and also an important driving force for the evolution of Chinese urban spatial organization structure.
基金sponsored by the Key Project(96-920-34-07)of the Ministry of Science and Technology,Chinathe Nationa1 Natura1 Science Foundation of China(40333027).
文摘Considering the urban characteristics, a customized multi-scale numerical modeling system is established to simulate the urban meteorological environment. The system mainly involves three spatial scales: the urban scale, urban sub-domain scale, and single to few buildings scale. In it, different underlying surface types are employed, the building drag factor is used to replace its roughness in the influence on the urban wind field, the effects of building distribution, azimuth and screening of shortwave radiation are added, and the influence of anthropogenic heating is also taken into account. All the numerical tests indicate that the simulated results are reasonably in agreement with the observational data, so the system can be used to simulate the urban meteorological environment. Making use of it, the characteristics of the meteorological environment from the urban to urban sub-domain scales, even the among-buildings scale, can be recognized. As long as the urban planning scheme is given, the corresponding simulated results can be obtained so as to meet the need of optimizing urban planning.
基金Under the auspices of National Natural Science Foundation of China(No.42001189,41471141)Opening Fund of Key Laboratory of Poyang Lake Wetland and Watershed Research(Jiangxi Normal University),Ministry of Education(No.PK2020006)。
文摘Based on urban physical space and theory of landscape ecology,a triune assessment framework—‘size-densitymorphology’—was constructed in order to analyze the spatial pattern and the scale effect of urban resilience in Shenyang of China in 2015,and to explore the main impact factors of landscape under different spatial scale backgrounds.The results show that:1)Urban resilience is an optimal combination of the resilience of size,density,and morphology.The urban resilience of Shenyang displays scale effect;the overall resilience level increases with the increase in scale,while the spatial difference and spatial similarity tend to decrease resilience.2)As 2 km,1 km and 2 km are scale inflection points of average value curves for size resilience,density resilience and morphology resilience,respectively in an urban setting;the optimal scale unit of comprehensive resilience is 1 km.Choosing 1 km–2 km as the basic spatial scale better depicts overall pattern and detailed characteristics of resilience in Shenyang.The spatial amplitudes of 0.5 km and 1 km are sensitive points for spatial autocorrelation of morphology and density resilience,size,and comprehensive resilience to scale effect.3)The major landscape factors of urban size and morphology resilience transform with scale expansion.Aggregation index(AI)has a significant impact on urban resilience at different scales;its influence increases significantly with the increase in scale.4)The high-level area of comprehensive resilience in Shenyang is the eastern ecological corridor area,while the low value area is the peripheral extension area of the city.To promote the overall level of resilience in Shenyang,this paper argues that the construction of ecological infrastructure should be strengthened in the peripheral extension area in a balanced manner.In the city center,population and building density should be controlled;the intensity of human activities should be reduced;impetus should be placed on landscape heterogeneity;and the homogeneous expansion of the area of construction should be prevented.In the eastern ecological corridors,the exploitation of ecosystem lands should be strictly controlled,and the integrity of the green landscape patches should be maintained.
基金This study was supported by the National Natural Science Foundation of China (Grant Nos. 40233030, 40405004, 40405014).
文摘The Regional Atmospheric Modeling System (RAMS) and the computational fluid dynamics (CFD) codes known as FLUENT are combinatorially applied in a multi-scale numerical simulation of the urban surface layer (USL). RAMS and FLUENT are combined as a multi-scale numerical modeling system, in which the RAMS simulated data are delivered to the computational model for FLUENT simulation in an offline way. Numerical simulations are performed to present and preliminarily validate the capability of the multi-scale modeling system, and the results show that the modeling system can reasonably provide information on the meteorological elements in an urban area from the urban scale to the city-block scale, especially the details of the turbulent flows within the USL.
基金Under the auspices of National Natural Science Foundation of China(No.41871162)。
文摘Scale is the range or measurement unit of the characteristics of natural or human ontology in the temporal or spatial dimension and is widely used in daily life and the study of various disciplines.Scale effect pertains to certain laws and characteristics that can only be reflected on a specific scale,so choosing the appropriate scale remains the basic premise of scientific research.The concept of the urban spatial system is complex and has the characteristics of scale dependence,and the selection of an appropriate spatial scale is important for the accurate estimation and description of urban issues.In this paper,we discuss spatial scale in urban research using cases that primarily come from the Chinese experience,provide some examples that demonstrate the importance of appropriate scale in urban research,including urban shrinkage,and highlight problems in spatial research.Ultimately,we suggest that scale consciousness should be the basic consciousness required in empirical research.
基金Zhejiang Provincial Academy of Social Sciences of China(No.2015N076)the Funding from Chinese Ministry of Environmental Protection,China(No.STSN-05-11)+2 种基金National Science-Technology Support Plan Project,China(No.2015BAC02B06)Natural Science Foundation of Zhejiang Province,China(No.LQ14D010003)Zhejiang Provincial Social Science Foundation of China(No.16NDJC145YB)
文摘The intensified conflict between island urbanization and lagging supervision deserves special attention worldwide.Zhoushan Island has been an outstanding center of marine economic development in China but also one of the areas most threatened by recent human activities.To cope with this challenge,the development of a retrospective understanding of the spatiotemporal dynamics of island urban growth is a key prerequisite.Detailed,multi-scales,long-term studies on island urban expansion are relatively rare.Remote sensing data,landscape metrics,and spatial statistics were used to characterize the urban landscape changes during the years from 1980 to 2013.Then,the potential determinants of island urban expansion were analyzed by integrating socioeconomic drivers,population factors,topographic variables,and policy guidance.The results indicate that Zhoushan Island has experienced a considerable urban expansion with an evident acceleration during the last period.Landscape changes in response to urban expansion varied with time,region,and scale.A general understanding of landscape metrics failed to reveal accurate dynamics for the urban landscape at a local level.At a block size of1 km,the urban landscape was more compact around the island urban center and the new developing zone,in contrast to the extensive and scattered pattern present across the entire region.Urban land primarily expanded from the urban center to the coastal regions due to topographic constraints and support from policy and economic benefits.The potential impact of the population factor decreased with urban growth,a finding that differs from several previous studies.The island urban dynamics observed in this study involved characteristics and differences that will guide future planning decisions and will provide a scientific case for urban development and sustainability with respect to islands and coastal regions in China.
基金Supported by the Land Use Plan Program of Dafang Bureau of Land and Resources[(2010)BCXY1209]the Sub-program"Graphics Construction in Dafang County"of the Land Use Plan in Dafang County of School of Economics,Guizhou University[(2011)1201]
文摘This paper is to examine the urban and rural construction land data of Dafang between basic year and final year based on country scale and spatial econometrics,and analyze its spatial pattern and change feature. According to the results,the construction lands in all the villages of Dafang County showed strong spatial autocorrelation and significant spatial cluster. After the analysis of local Moran's I,the construction lands in 381 villages of 36 counties presented strong activity. The original small-scale villages were gradually enlarging,which will not only gradually benefit local development,but also be in accordance with the strategy of " one city,one district,eight parks".
基金Funded by Independent Innovation Grant of Huazhong University of Science & Technology (No. M2009013)
文摘Urban rail transit(URT) has been playing an important role in urban sustainable development with its advantages of high speed,large capacity,high efficiency and low pollution.Estimating URT network scale is the key to ensure the scientificity and feasibility of its construction.The existing studies on rational scale of URT network have not dealt with the interaction of supply and demand.This paper describes the establishment of a system dynamics model of rational URT network scale determination,considering the interaction between URT construction and city social economic development as well as the dynamic equilibrium of capital supply and traffic demand,and the verification of the model validity by applying it to the case of Wuhan City's URT construction.