中国城市化进程中的滞后城市化、超前城市化与城市中空化趋势

中国特殊的国情与发展阶段决定了中国城市化进程的复杂性。本文对发达国家城市化过程中出现的“城市中空化”以及发展中国家出现的“超前城市化”和“滞后城市化”现象进行分析探讨,结合中国城市化进程作实证分析,得出我国城市化总体上处于滞后状态,但超前化和中空化趋势同时存在。对中国城市化特征的正确判定,将有利于城市规划中的科学决策。

中国城市化进程中的滞后城市化、超前城市化与城市中空化趋势

中国特殊的国情与发展阶段决定了中国城市化进程的复杂性。本文对发达国家城市化过程中出现的“城市中空化”以及发展中国家出现的“超前城市化”和“滞后城市化”现象进行分析探讨,结合中国城市化进程作实证分析,得出我国城市化总体上处于滞后状态,但超前化和中空化趋势同时存在。对中国城市化特征的正确判定,将有利于城市规划中的科学决策。

我国城市化进程中存在的问题及建议

工业化、城市化和现代化是现代社会历史发展过程中三个相互影响、相互作用的重要因素。我国目前正处于城市化的加速时期,城市化建设取得了瞩目的成就,城市规模不断扩大、数量不断增加、以城市人口增长为标志的城市化率稳步提高。伴随着我国城市化进程的推进,贫困问题、公共安全管理问题、资源短缺问题、城市化与产业结构不协调问题、城市特色危机等问题也随之出现,这些复杂的问题交错在一起,不仅会阻碍我国的城市化和现代化进程,也会带来一系列的更深层次的社会问题,必须要科学妥善地加以解决。

Gentrification and Residential Differentiation in Nanjing,China

The institutional environment in China has quite evidently changed during modern socio-economic transitions.Driven both by local government and by marketing force,urban social space was redistributed after the reform of urban land and real estate policies.Urban renewal makes for wide differential rent and therefore gentrification is occurring in China.This paper analyzes the background and institutional environment of gentrification in China,and further discusses the process,characteristics and evolutionary mechanisms in the case of Nanjing,through investigation of the attributes of 1075 residential communities built during the 1998-2008 at a macro level,and interviewing the residents and analyzing questionnaires in 6 different and typical communities at a micro level.As a socio-spatial course of two-way interaction,gentrification is divided into 3 stages of incubation,occurrence and fast development,according to the time of landmark events and policy reform on the leasehold of land in Nanjing during socio-economic transition.In terms of the socio-spatial characteristics of gentrification in Nanjing,the gentrification process under the trajectory of urban renewal makes urban social space present a new circle-layer structure;the rise of quite a number of gated communities results in the fragmentation of social space and privatization of public space;the management mode of modern communities and the change of life style have aggravated the indifference of neighborhood relationship of gentrified communities.Based on the empirical evidence of this study,this paper indicates that gentrification is quite different between China and western countries with respect to spatio-temporal order,dominant forces,paths of realization and spatial expression,and it further reveals the dynamic mechanism of gentrification developing in China at the present stage.

Spatial and Temporal Variability of Farm Size in China in Context of Rapid Urbanization

During the last 30 years, China has witnessed rapid economic growth and dramatic urbanization, with about 1.2 x 107 rural people migrating annually into urban areas. Meanwhile, especially since 1995, the rural population has been declining, which is closely linked to land circulation and the increase in farm size in many villages. Increasing scale of farming operations is often regarded as a key to avoiding the abandonment of farmland and to increasing the income of rural farmers. However, until now, there has been little research on the spatial and temporal variability of farm size at the national level in China. Using data from the national agricultural cen- sus and rural household surveys, this study examines the characteristics of land use circulation and the consequent changes in the area of farmland per household. The results show that： 1） 12.2% of rural households were involved in land circulation at the national level. The highest amounts of land circulation have occurred in those provinces where the farmland per capita is more than 0.2 ha or less than 0.1 ha; 2） over 80% of households operate less than 0.6 ha of farmland; 3） the proportion of mid-sized farms （between 0.2 ha and 0.6 ha per household） has decreased while the smallest and the largest farms have increased. This bears some similarity with the phenomenon known as the ＇disappearing middle＇, referring to the changes in farm size. This study establishes a framework for interpreting the factors affecting the changes in farm size in China, which include two promoting factors （urbanization and agriculture） and four hindering fac- tors （agricultual land system, household registration, stable clan system, and farmland loss）.

Environmental Effects of Foreign Trade and Its Spatial Variations in Mid-eastern Provinces and Cities of China

The studies on environmental effects of foreign trade and its spatial variations are helpful to design and implement environmental protection countermeasures.In order to eliminate the adverse effects of insufficient observation values on the accuracy of regression results and dynamic information quantity of fitting equation during empirical study,panel data of the mid-eastern provinces and cities of China from 1985 to 2007 were selected based on the adjustment of classical regression model in this paper.Panel unit root test and panel cointegration analysis method were applied to investigating the environmental effects of foreign trade and its spatial variations in the mid-eastern provinces and cities of China and its three groups divided by foreign trade dependence.The results show that all scale effects are positive,while all technical effects are negative and unable to counteract positive scale effects.Foreign trade development is regarded as an important cause for outstanding eco-environmental problems in the mid-eastern provinces and cities of China.Total effects and structural effects are significantly different among different groups because of spatial variations in environmental policies,export destinations,source of FDI,etc.Following the principle of′coordinating generality and considering differences comprehensively′,it is essential to issue a series of policies and countermeasures corresponding to differences in regional environmental effect of foreign trade,in order to coordinate the relationship between foreign trade development and eco-environment in each region.

Elemental Analysis of Air Suspended Particles in Rasht City Using Instrumental Neutron Activation Analysis

Instrumental neutron activation analysis （INAA） has turned out to be particularly useful in the analysis of suspended particles. This work describes the INAA characterization of air particulate matter collected in Rasht city, Iran. The particulate matter was collected in two sampling sites for elemental analysis in the period of winter-summer 2009. Samples have been transferred to the environmental laboratory of radiation applications research school. Neutron exposures were performed in Tehran Research Reactor, and measurements were carried out using HPGe detectors coupled to gamma ray spectrometer. In these filter samples, the elements, AI, As, Ba, Br, Ca, CI, Co, Cr, Cu, Fe, Hg, K, La, Mg, Mn, Na, Sb, Sc, Ti, V and Zn were determined using different irradiation and counting protocols. Results show that mean concentration of most air-pollutants in Rasht are lower than those measured in other cities in Iran （Tehran, Shiraz, Isfahan）. Collected data were also compared with reported results for other cities in the world.

Semi-urbanization and evolving patterns of urbanization in China: Insights from the 2000 to 2010 national censuses

Based on the prefecture-level data of the 2000 and 2010 national censuses, the spatial evolution of China's semi-urbanization is analyzed in this study. The stages of urbanization are re-examined by considering semi-urbanization. Nine types of urban development are presented according to the relations between semi-urbanization and urbanization, and China's urbanization is divided into five stages, namely, high incoordination, incoordination, low coordination, coordination, and high coordination. Results show that China's semi-urbanization rate varies significantly from one area to another; its order in 2010 from the highest to the lowest value was as follows: east, middle, west, and northeast. Urbanization and semi-urbanization rates in inland cities increase much faster than those in coastal cities. In addition, semi-urbanization displays a spatial pattern similar to that of urbanization across China, with the sole exception of the northeastern region. Through a spatial autocorrelation analysis, the spatial concentration of semi-urbanization is determined to be increasing. High-value concentration areas are expanding in the coastal east, whereas low-value concentration areas are growing in the northeast. Lastly, the evolution of China's urbanization model suggests a weakening trend of coordination between urbanization and semi-urbanization over the studied decade. Semi-urbanization can be viewed as a special production of China's hukou system, which restricts the permanent settlement of migrants in cities. As such, China's semi-urbanization trend is expected to exhibit a reversed U-shaped pattern as urbanization and citizenization develop.

Comparative research on regional differences in urbanization and spatial evolution of urban systems between China and India

As two rising great powers, China and India have undergone similar development processes, but they also exhibit significant differences in development paths and patterns. The significant differences in political systems, economic systems, and developmental environment between the two countries have attracted great attention from scholars. This research focuses on the regional differences and spatial evolution processes in urbanization and urban systems between the two countries from a geographical perspective. Based on the demographic censuses of both countries and the urban population data from the United Nations, this paper systematically compared and analyzed the spatial characteristics of urbanization and urban systems in China and India using various methods including spatial analysis, parameter estimation, and nonparametric estimation. The results indicate that:(1) Since the 1990 s, the regional differences in urbanization in China have transformed from south-north differences to coastal-inland differences, whereas the north-south differences in India have been stable.(2) In recent years, the correlation between population density and urbanization rate kept increasing in China, while such correlation has been decreasing in India.(3) The economic reform posed significantly different effects on the spatial evolution of the urban systems in the two countries. The economic reform changed the major driving force for urban development in China from geographical and historical factors to the spatial structure of the economic system. However, in India, the driving forces for urban development have always been geographical and historical factors, and the economic reform even decreased the effect of the spatial structure of the economic system on urban development.

Research on Newly Urbanized Towns and Districts in China

Since the last decade the central government endeavors to promote large scale of urbanization in China.Lots of new urban towns and districts are taking shape. Outline of the 12th Five-year Plan released by the central government points out that the new towns and districts are to be regulated. But few researches are considering the new towns and districts especially in the spatial distributive pattern and status in China. Given this situation this paper, after sorting out the world-wide research and development of new urban towns and districts, gives definitions of broad and narrow meanings. Based on the broad meaning definition, the database of new towns and districts in China is established. This paper then conducts a preliminary analysis of the new towns and districts.Then the two-step work plan and the advices are also proposed to further improve the research and practice of its kind in China.