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1.
As the Central Place Theory indicates, the centricity of a central city can influence the extension of its service. Since the service industry in the theory is mostly consumer services, it is worth studying the relationship between the producer services and the centricity of the city in the service society with producer services becoming a more important part of the service industry. The paper takes the case of the Zhujiang （Pearl） River Delta （PRD）, a developed region in China, to study the relationship between the developing level of producer services and the urban hierarchy. Based on the analysis about the spatial difference of the producer services in the nine cities of the PRD, and the division of the nine cities according to some economic indices, it is shown that there is a correlation between the developing level of producer services and the urban hierarchy. Furthermore, two deductions about the future status of the producer services in the city and the location of the producer services in a large region can be made from this correlation between the developing level of producer services and the urban hierarchy.  相似文献   

2.
This study focuses on the suburbanization and subcentering of population and examines the nature of spatial restructuring in terms of the population distribution in the Beijing metropolitan area.Instead of the classic density function approach,we employ the nonparametric analysis to characterize the spatial pattern of population densities in the Beijing metropolitan area and identify the suburban subcenters.Our findings suggest that the population has spread with rapid urban growth in the Beijing metropolitan area,and the compact urban form has been replaced by a more dispersed polycentric spatial distribution.However,compared with the decentralization of western cities,the spatial extent of the decentralization of population in the Beijing metropolitan area is quite limited.The rapid growth of population in the near suburbs has expedited the sprawl of the central city,with a larger central agglomeration of population dominating the metropolitan area.In this sense,the spatial pattern of the Beijing metropolitan area is still characterized by the continuous compactness.However,our findings do provide the evidence that the city has been turning to a polycentric structure.We find significant population subcenters have emerged in the suburbs of Beijing since the 1980s.But the polycentricity emerged in the Beijing metropolitan area is very different by nature from that observed in Western cities.The subcenters emerged are adherent to the development scheme planned for the city,so it can be referred to as the so called ’planned polycentricity’.  相似文献   

3.
The connectedness between cities has become one of the most widely discussed topics in urban and regional research in the mobile and big data era. One problem identified is the asymmetric city connectivity, partially due to data availability. We present a data-driven approach based on location and toponym(place name) extracted from social media data, to assess the asymmetric connectivity between cities. The assumption is that a higher frequency of occurrences of the name of city i in posts located in city j would imply that the city i is more influential than other cities upon city j. In addition, we’ve developed a group of measurements such as the relatedness index, impact index, link strength index, dependence index, and structure similar index to characterize such interactions. This framework of connectivity measurements can also be used to support smart planning taking into account the evolving interplay among cities. The space-time structure of urban systems in China is examined as the case study.  相似文献   

4.
Based on the National Land Use/Cover Database of China(NLUD-C) in the end of the 1980s(the 1980s,hereafter), 1995, 2000, 2005, and 2010, 665 cities were selected to study the size distribution and its changes of urban lands in China. In this study, the spatiotemporal evolutions of urban land size distribution as well as the influence of administrative-level on these cities were explored by combining urban spatial positions and administrative-levels. Results indicate that: 1) City size distribution using urban lands was more practical and reasonable than using non-agricultural population. 2) In the 1980s, cities with ascending urban land rank were centralized in Eastern China, specially the Changjiang(Yangtze) River Delta, the Zhujiang(Pearl) River Delta, and Beijing-Tianjin-Hebei region. Cities in Central, Western, and Northeast China mainly indicated descending urban land rank. 3) The transfer of national development focus resulted in cities with ascending urban land rank becoming evenly distributed nationwide; however, this trend was slightly centralized around Chengdu, Chongqing, and Wuhan in different periods. 4) During the 1980s to 2010, the proportion of cities with ascending urban land rank in provincial capitals, municipalities, and special administrative regions(high-level cities, hereafter) was consistently higher than those in prefecture- and county-level cities except for 2005–2010. The ranks of the majority of the prefecture- and county-level cities were mainly descending, supported by ascending; the proportion of cities with unchanged rank is small. This study breaks through the bottleneck of traditional research in the area of city size distribution by examining urban land replacing the non-agricultural population. The current study also provides scientific explanation for the healthy and reasonable development of urban land as well as the coordinated development of population urbanization and land urbanization.  相似文献   

5.
Since 1949, great changes have taken place in the amount and distribution of China's urban population. From the analysis on the change in total urban population, it can be learnt that urbanization progress can be controlled mainly by social-economic development and government policy through influencing the migratory growth of urban population and the number of organic cities. In the period 1949-1990, the states of megalopolises had gone up; medium-sized cities had decreased. It is estimated that the total urban population of China will still increase at a rapid speed in the coming 10 years; there will not be great changes in grade system of urban scale; and urban population may shows a tendency to move to coastal area.  相似文献   

6.
The Taihu Lake region in southern Jiangsu is one of the regions with flourishing economy and the highest level of urbanization due to favourable natural conditions and socio-economic foundation. However, there emerge a seriers of urban ecological problems on continuous stretch of cities and towns, a vague division of urban functions, ground subsidence, serious pollution of atmosphere and waters arising from dense population, irrational distribution of industry, backwardeness of municipal engineering facilities, and inexperienced scientific management of water resources. In order to improve the urban eco-environment in this lake region, we should work out an overall regional eco梕nvironmental programme, perfect the urban economic set-up from the reqirements of urban material circulations and energy exchanges, and finally put into practice the urban functional regionalism, so that the Taihu Lake region in southern Jiangsu has not only a higher economic benefit, but also a beautiful and comfortable eco-env  相似文献   

7.
Metropolises are centers of politics, economy, culture and information, and also economic growth poles in comparatively large areas. After 1949, China's urban structure have changed greatly, from original "pyramid" shape into "upside -down pyramid" shape, that is, more megalopolises and metropolises, fewer medium-sized and small cities. The most distinguishing feature of urban population growth was the remarkable increase of population in megalopolises and metropolises. The key reason for urban population expansion is to want to obtain the benefits of scale -agglomeration economy of metropolises. The number of urban functions directly determines the quality and quantity of urban population. Metropolises appeal not only agricultural population but also the population of medium-sized and small cities, which put much more population pressure on metropolises. The ideal goals of scale-control of metropolitan population are discussed in terms of economy, society and ecollogy. In order to control the metropoli  相似文献   

8.
Urban air pollution is a prominent problem related to the urban development in China, especially in the densely populated urban agglomerations. Therefore, scientific examination of regional variation of air quality and its dominant factors is of great importance to regional environmental management. In contrast to traditional air pollution researches which only concentrate on a single year or a single pollutant, this paper analyses spatiotemporal patterns and determinants of air quality in disparate regions based on the air quality index(AQI) of the Yangtze River Delta region(YRD) of China from 2014 to 2016. Results show that the annual average value of the AQI in the YRD region decreases from 2014 to 2016 and exhibit a basic characteristic of ‘higher in winter, lower in summer and slightly high in spring and autumn'. The attainment rate of the AQI shows an apparently spatial stratified heterogeneity, Hefei metropolitan area and Nanjing metropolitan area keeping the worst air quality. The frequency of air pollution occurring in large regions was gradually decreasing during the study period. Drawing from entropy method analysis, industrialization and urbanization represented by per capita GDP and total energy consumption were the most important factors. Furthermore, population agglomeration is a factor that cannot be ignored especially in some mega-cities. Limited to data collection, more research is needed to gain insight into the spatiotemporal pattern and influence mechanism in the future.  相似文献   

9.
In traditional urban geography, city contact research is a classic study element in city research. In general, researchers use the traditional gravity model to characterize the contacts that exist between two cities. The traditional gravity model assumes ideal condi- tions, but these preconditions and their results often do not exist in realistic conditions. Thus, we used a modified gravity model to char- acterize the city contacts within a specific region. This model considers factors such as intercity complementarities, government inter- vention, and the diversity of the transportation infrastructure which is characterized as the transportation distance instead of the tradi- tional Euclidean distance. We applied this model to an empirical study of city contact in the Zhujiang （Pearl） River Delta （PRD） of China. The regression results indicated that the modified gravity model could measure city contact more accurately and comprehen- sively than the traditional gravity model, i.e., it yielded a higher adjusted R2 value （0.379） than the traditional gravity model result （0.259）. Our study also suggests that, in addition to urban-regional and metropolitan development, the complementarities of the basic functions of cities at the administrative and market levels, as well as the corporeal and immaterial levels, play very significant roles in the characterization of city contact. Given the complexity of city contact, it will be necessary to consider more relevant influential fac- tors in the modified gravity model to characterize the features of city contact in the future.  相似文献   

10.
The spatial form of urbanization in China has developed from single-core city expansion to a multi-center metropolitan area.However, little attention has been paid to the growth process of the emerging metropolitan area situated in major grain producing locations in the central China. Taking the Zhengzhou metropolitan area(ZZMA) as a case study, we developed an inverse S-shape model to characterize the spatial distribution of urban land density, and constructed an urban expansion core index, urb...  相似文献   

11.
The 2000s has witnessed increasing interests in cities′role of innovation in the era of knowledge-based economy.Compared with substantial empirical analysis on the world city hierarchy of innovation,this paper attempts to examine the national urban hierarchy of innovation capability in China,in terms of ranking systems,spatial pattern and inter-city linkages of knowledge during the post-reform period since the late 1970s.Based on quantitative analysis such as principal component factor analysis and clustering analysis,this paper identifies the five-tier hierarchy of in-novation,which is headed by Beijing and Shanghai,followed by the capital cities of each province and regional centre cities.The development of China′s urban hierarchy of innovation capability has been driven by such factors as the scale of innovation,scientific scale,innovation potential and innovation environment.The paper further investigates the inter-city linkages of knowledge measured by the number of co-authored papers among the cities.Beijing is positioned in the central position of the knowledge diffusion and knowledge cooperation innovation.More knowledge diffusion among high level cities has occurred than that among the low level cities as well as between the low level cities and high level cities,and provincial capital cities and the regional central cities.  相似文献   

12.
The housing vacancy rate(HVR) is an important index in assessing the healthiness of residential real estate market. In China, it is hardly to take advantage of the basic data of real estate information due to the opaque of those data. In this paper, the HVR is estimated to two scales. At the grid level, urban area ratio was calculated by nighttime images after eliminating outliers of nighttime images and night light intensity of non-residential pixels in mixed pixels by a proposed modified optimal threshold method, and built-up areas in each pixel were extracted from the land-cover data. Then, the HVR is calculated by comparing the light intensity of specific grid with the light intensity of full occupancy rate regions. At the administrative scale, the GCI(‘ghost city' index) is constructed by calculating the ratio of the total light radiation intensity of a city to the total construction land area of the city. The overall spatial differentiation pattern of the vacant houses in the national prefecture level administrative regions is analyzed. The following conclusions were drawn: vacant housing is rare in certain eastern coastal cities and regions in China with relatively fast economic development. Cities based on exhausted resources, some mountainous cities, and cities with relatively backward economic development more typically showed high levels of housing vacancy. The GCI of prefecture-level administrative units gradually declined from north to south, whereas the east-west distribution showed a parabolic shape. As city level decreased, the GCI registered a gradual upward trend. China's urban housing vacancy can be divided into five categories: industry or resources driven, government planned, epitaxy expansionary, environmental constraint and speculative activate by combining the spatial distribution of housing vacancy with the factors of natural environment, social economic development level, and population density into consideration.  相似文献   

13.
Dalian, Shenyang, Changchun and Harbin are the four core cities which play an essential role in terms of promoting the economic development in Northeast China. In this paper, the impact of urban agglomeration on labor productivity is explored by making comparisons among these four cities. The model used for analysis is a classical model derived from previous studies. Some indicators, such as population density and economic density, were selected to examine the impact of urban agglomeration on the labor productivity based on the time-series data for the four cities from 1990 to 2007. The four main conclusions are: 1) The promotion from the growth rate of population density on the growth rate of labor productivity is limited. 2) The negative relationship exists between the growth rate of employment density and the growth rate of labor productivity. 3) Agglomeration effect exists in the four cities, the highest one is Dalian, Shenyang takes the second place, followed by Changchun and Harbin, and the predominant promotion exerted on the labor productivity is the output density.  相似文献   

14.
This paper examines city growth patterns and the corresponding city size distribution evolution over long periods of time using a simple New Economic Geography(NEG) model and urban population data from Canada. The main findings are twofold. First, there is a transition from sequential to parallel growth of cities over long periods of time: city growth shows a sequential mode in the stage of rapid urbanization, i.e., the cities with the best development conditions will take the lead in growth, after which the cities with higher ranks will become the fastest-growing cities; in the late stage of urbanization, city growth converges according to Gibrat′s law, and exhibits a parallel growth pattern. Second, city size distribution is found to have persistent structural characteristics: the city system is self-organized into multiple discrete size groups; city growth shows club convergence characteristics, and the cities with similar development conditions eventually converge to a similar size. The results will not only enhance our understanding of urbanization process, but will also provide a timely and clear policy reference for promoting the healthy urbanization of developing countries.  相似文献   

15.
This is an empirical paper that measures and interprets the position of Chinese cities in the world city network in 2010. Building on a specification of the world city network as a′interlocking network′in which business services firms play the crucial role in city network formation, information is gathered about the presence of global service firms in cities. This information is converted into data to provide the′service value′of a city for a firm′s provision of corporate services in a 526(cities)×175(firms) matrix. These data are then used as the input to the interlocking network model in order to measure cities′connectivity and its predominant geographical orientation. Here we focus on the position of some key Chinese cities in this regard, and discuss and interpret results in the context of the urban dimensions of the′opening up′of the Chinese economy.  相似文献   

16.
Currently domestic researches on urban imago space concentrate in a few cities that lie in the advanced region, such as Beijing, Guangzhou, Wuhan, etc., but in so far as those cities that lie in the northwest inland region, the research of this aspect is still few. In order to supplement a special example to the urban imago space theory and to validate former theory, this article studied the Lanzhou urban imago space. During the course of researching, authors adopted some investigating methods, such as visiting on the spot, photograph identification method and sketch man identification method etc. Using investigated data, this paper made an elementary research on urban imago space of Lanzhou, which is a typical valley city in the western China. The result of study indicated that the urban imago space of Lanzhou takes Xiguan Cross as its center (Lanzhou involves four districts of Chengguan, Qilihe, Arming and Xigu). In the process of recognition of urban imago space, the Huanghe (Yellow) River and mountains beside the city are the dominant factors and the main nodes of cognition. So the urban imago space of Lanzhou is quite different from that of plain cities. Interviewee did well in the spatial structure map, which was made up of mountainous land, river and main trunk roads, the group structure took profound impression on people.  相似文献   

17.
Chinaˊs urban reforms have brought social progress and development,but a comprehensive national system of social welfare(for example,unemployment insurance,pensions,medical care and public housing)for new migrants from rural areas is lacking.One of the most remarkable changes in Chinese cities in the last decade was a change in so-cial“equality“,with the rise of new poverty both in individual communities and some social groups in urban society.Howev-er,there is little social assistance and public infrastructure for the migrants.Governments or communities or individual should pay attention to the control of new urban poverty and new slums.This paper consider that it is necessary to launch a successful policy,which include mainly:1)accommodating urban growth through low-cost investment projects;2)ur-ban economy depends heavily on successful macroeconomic policy;3)to broaden the three channels linking adjustment to the incidence of urban poverty;4)to restructure urban economic based on the high or new technology;5)to coordi-nate relationship between urban economic growth and environment management for sustainable development of Beijingˊs metropolitan fringe.  相似文献   

18.
Understanding the dynamics of urbanization is essential to the sustainable development of cities. Meanwhile the analysis of urban development can also provide scientifically and effective information for decision-making. With the long-term Defense Meteorological Satellite Program’s Operational Linescan System(DMSP/OLS) nighttime light images, a pixel level assessment of urbanization of China from 1992 to 2013 was conducted in this study, and the spatio-temporal dynamics and future trends of urban development were fully detected. The results showed that the urbanization and urban dynamics of China experienced drastic fluctuations from 1992 to 2013, especially for those in the coastal and metropolitan areas. From a regional perspective, it was found that the urban dynamics and increasing trends in North Coast China, East Coast China and South Coast China were much more stable and significant than that in other regions. Moreover, with the sustainability estimating of nighttime light dynamics, the regional agglomeration trends of urban regions were also detected. The light intensity in nearly 50% of lighted pixels may continuously decrease in the future, indicating a severe situation of urbanization within these regions. In this study, The results revealed in this study can provided a new insight in long time urbanization detecting and is thus beneficial to the better understanding of trends and dynamics of urban development.  相似文献   

19.
Exploring long-term residence among the urban floating population is crucial to understanding urban growth in China, particularly since the 2008 financial crisis. By using China Migrants Dynamic Survey data for 2012–2014, China Labor-force Dynamics Survey data for 2014–2016, and macroscale urban matched data, we analyzed the spatial pattern of long-term residential behavior in China's urban floating population in 2012–2016 and developed an urban spatial utility equilibrium model containing ‘macro' urban factors and‘micro' individual and household factors to explain the pattern. The results first revealed that long-term residence is defined as ≥ 6 yr for the urban floating population in China. Second, members of this population are more likely to be long-term residents of the megacities in the three urban agglomerations in eastern China as well as of small and medium-sized cities in western and northeastern China, whereas short-term residence is more likely in cities in central China and near the three urban agglomerations. Third, urban population density and housing prices, both have a significant U-shaped effect, are main factors affecting the spatial pattern of long-term residence.  相似文献   

20.
Character and Causes of Population Distribution in Shenyang City, China   总被引：1，自引：0，他引：1  
1 Introduction Research on the character of urban population distribu- tion is one of the focuses of western urban geography. From the 1950s, the research has attracted the attention of many western researchers, and a series of classical theoretical models were put forward. For example, Clark (1951) found that with the increase of distance from the city center, the urban population density tends to de- crease in exponential. Through the statistical analysis of more than 20 cities, he put forw…  相似文献   

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