With rapid socioeconomic development, the effect of urban green space on the ecological environment and living environment in cities has attracted increasingly more attentions. Meanwhile, due to the expansion of built-up areas, urban green space is becoming a scarce resource. A spatial mismatch exists between the supply and demand of urban green space because the quantity and quality of green space in urban centers fall short of meeting the increasing demands of the growing urban population for recreation and good health. Therefore, the planning, design, utility, and function of urban green space have become an important area of urban geography research and urban planning practice. Drawing on the recent progress in research, the paper introduces the concept of urban green space and its evolution. It also synergizes the literature of various disciplines to produce a systematic understanding of the role of urban green space in promoting ecological services, social life, and economic value of land. Main challenges include: the lack of policy and measures for effectively incorporating green space into urban spatial development, inadequate treatment of improving the quality of urban green space, and mismatch between the supply and demand of the urban green space. Therefore, we argue that green space is another important urban space other than economic and social ones. This important topic in urban geography raises new but important issues: (1) incorporating urban green space as a way of enhancing urban sustainability; (2) improving current urban planning by emphasizing the social, economic, and ecological functions of cities; (3) extending the horizon and topics from traditional descriptive research on the distribution and spatial characteristics of urban green space to look at the interaction between green space and socioeconomic development; and (4) urban geography should play a role in synergizing and facilitating multi-disciplinary research on urban green space, but needs both quantitative and qualitative methods.

Abstact: China is meeting the grand challenge while facing many problems brought by the rapid urbanization in the past decades. As a result, effective policies are called for to assure the sustainability of urban spatial development. Modeling urban spatial development process for policy test would be of great significance for decision making and the eventual realization of sustainable urbanization. The objective of this paper is to establish an operative model to simulate urban spatial evolution process that would help to formulate urban spatial policies. Land-use/transport interaction model (LUTI) is considered an important tool to model urban spatial development processes. We think that urban land use reflects the spatial distribution of urban economic and social activities, and urban expension and land use changes reflect the changes of urban activity distribution caused by the interaction between land use and transport. Using the LUTI concept and taking economic and social activities as an enentry point, we built an urban activity spatial evolution model (UASEM) and discussed the implementation of this model in details. UASEM includes a number of submodels, including an Activity Transition Model that predicts the amount of activities, an Estate Development Model that predicts the floorspace of buildings, a Transport Model that evaluates transport accessibility, and an Activity Location Model that predicts the spatial distribution of socioeconomic activities. The paper introduces the implementation of each submodel of the UASEM and maps the relationship between them, so the UASEM given in this paper is an operative model. UASEM is a computer model that includes an itarative programe, which simulates the iterative process of urban land use and transport interaction. To ensure that the model results converge, boundary condition of the model is carefully examined. UASEM is a dynamic model that takes into account the change of every activity. The spatial and tempral dimensions of UASEM need to be decided according to the urban scale and data availability. Towns are normally the basic spatial unit of analysis and the temporal scale of such analysis is often annual. UASEM results provide a reference for researches of urban modeling and analysis in China.

Cities are centers of surrounding regions and play an important role in regional economic and social developments. Approaches for achieving sustainable urban development has been a hot topic in the study of human- environment relationship. However, the dynamic mechanism of sustainable urban development is relatively neglected in existing urban sustainability studies. In this research, emergy analysis method was used to measure the level of sustainable urban development. On the basis of this analysis, we built a new model of Sustainable Development Kuznets Curve (SDKC), and used Quanzhou City as a case to analyze the dynamic relationship of economic growth and level of sustainable urban development. In addition, an improved model of degree of grey slope incidence was used to preliminarily examine the causes of the SDKC. The results show that the SDKC of Quanzhou City reveals a U-shaped relationship between the level of sustainable urban development and economic growth; the level of sustainable urban development was in negative correlation with economic scale, proportion of secondary industry, proportion of tertiary industry, export dependence, and the influence of government. The generalized pollutant discharge reduction technologies, proportion of primary industry, and foreign investment played a positive role on the level of sustainable urban development. According to the results, we put forward some recommendations on promoting sustain development of the city for decision-makers, including facilitating the transformation of economic growth mode to strengthen the positive effect of modern service industry for sustainable development; adjusting export structure and improving the efficiency of exports; avoiding repetitive public infrastructure development; strengthening technological innovations to promote energy conservation; stringent environmental regulation and barriers to entry, among others. The results of this study may provide some references and foundations for the city government to accurately grasp its sustainable urban development status and dynamic mechanism, and formulate policies that are scientifically sound for sustainable urban development.

With the rapid development and wide-spread use of the Internet, online shopping, which is defined as an activity to search or purchase services or goods via the Internet, has become a new shopping media and method. Online shopping competes with traditional retailing and these two complement each other, and it reshapes people's shopping behavior and retail operation mode, thus changing the traditional retail layout and land use. This paper introduces the research of geography in recent 20 years on online shopping, personal travel, and retail space and points out that online shopping is a substitution, supplement, or correction of personal travel on shopping trips. There are three effects of online shopping on retail space: (1) expansion and fragmentation of activity space; (2) the retail space changes from a single physical space to a combination of cyber and physical spaces; (3) online retail activities infiltrate and mix with other spaces and stimulate the transformation of traditional retail space. These changes provide a basis for relevant research on the development of urban traditional retails. This paper attempts to provide a reference for commercial space planning, consumer travel optimization, and urban traditional retail development and transformation.

Urban form is defined as a figure presentation of spatial pattern of city's external shape, and, together with urban pattern and urban morphology, constitutes the three subjects at different levels in the research field of urban morphology. Current studies on this subject ignored the identification of the growth process from sprouting, growth, maturity, to ageing, and its impacting factors such as historical, political and social structure. Urban form is the lowest level in the urban morphology field. However, it has a very close relationship with urban growth process and the influence factors, it is an important knowledge basis for further understanding urban pattern and urban morphology, and it is also beneficial to grasping the expansion process of the boundary of urban built-up areas and making rational measures to control the trend of urban growth. Furthermore, coastal cities that sprouted in the estuarine always have unique growth characteristics different from others cites, because of their dependence on waterway transportation in early times. For example, early urban expansion nearby a port may be related to estuaries, rivers i.e., and the correlation would weaken in the process of social and economic development. How to quantitatively describe this evolution process and influence factors? This is a question that still needs to be further discussed by using new methods and defining new spatially related indices. Therefore, based on multi-type historical maps and multi-temporal remote sensing images, this paper first employs geographic information system (GIS) software ArcGIS Desktop 10.01 and remote sensing (RS) images processing platform ERDAS Imagine 2011 to extract the information of built up area boundary of Shanghai from 1842 to present, a 170-year time period, and secondly, calculates the fractal dimension (FD) and related circumscribing circle (RCC) of built-up area boundary by Fragstats 4.1 software to measure the complexity of urban boundary expansion, use ArcGIS Desktop 10.01for statistical analysis of the fan-shaped areas of built-up area expansion in different directions such as East, West, South, North, to identify the directional characteristics, and define an index urban hydrophilic property (UHP) to express the attraction of Huangpu River and Wusong River to built-up area boundary extension. All of these metrics finally are used for analyzing the historical evolution process and characteristics of the built-up area boundary of Shanghai City. In addition, with the reference to the historical literature, this paper discusses the impact of social transformation on the urban form evolution of Shanghai. The results show that: (1) FD and RCC of urban boundary showed a rise pattern of "M"; (2) urban boundary expansion showed a "single-direction" or "full-direction" mode during different historical periods; (3) the attractive effect of Huangpu River and Wusong River on built-up area boundary expansion has weakened due to the development of public transport system on the land; (4) complexity and directions of urban built-up area boundary showed significant stage characteristics along with the historical evolution process, which is mainly driven by different levels of social and economic development in the historical periods. The conclusion of the study is of reference value to Shanghai government in planning a more sustainable urban form in the future, and also makes a significance contribution to the extension of the theories and methods of urban morphology study.

China has undergone an institutional transition from welfare-oriented to market-oriented housing allocation system since the year of 1978. Housing reform was closely related to social change and economic reform. Thus, it has significant influences on socioeconomic conditions. Housing resource is an important indicator of social stratification. In this paper, Xiamen City is selected as a research area. The city incorporates a variety of residential patterns in different periods including transitional communities with local characters, post-reform communities, commercial communities and city villages. The housing resource data was obtained by spatial sampling and survey. We conducted a field study with 1075 face to face questionnaires. More than ten years after the housing allocation system was stopped, housing ownership was characterized with diversity in terms of income, education, family size and occupation. The empirical results showed that people have various sources to obtain houses. Commercial house in real estate was the primary housing source, accounting for 56% of the residents with house ownership. Public house was ranked as the second source, accounting for 33.4%, which was still an important source after the housing reform due to path dependence. The logistic regression results showed family income, education and family size, multiplied, increased the probability of housing ownership which has positive feedback to self-identification of social status. Income and occupation have positive feedback to housing resource. For non-public economy unit job holders and high income group, they have more opportunities to access the public houses at a lower price, and gained more profits in the real estate market. This paper explored the driving mechanism of the housing stratification by using time series and cross-section data. The housing reform process was divided into four stages. The cluster analysis indicated the housing expenditure gap among low income, median income and high income groups, increased during the housing reform process. But the time series data didn't verify the cause-and-effect relationship. Structural equation model using cross-section data was further used to verify the relationship between housing ownership and its influencing factors. Family income has strong effect on the probability of housing ownership, followed by education, while occupation and family size have least effect. Income and housing ownership in turn have direct effect on self-identification. The interaction between income and occupation indicated that housing resource stratification resulted from economic and institutional factors. After housing reform, the house distribution system should consider the housing gap induced by economic status and occupational prestige and expand the coverage of welfare housing. Current housing resource was still influenced by the previous distribution system. And residents have flexible choices on residential location and housing resources, which would accelerate the complexity of urban changes. This research quantified the current situation of housing resource stratification, and then further analyzed its mechanism and effects. The research in this paper has enriched the theory of social stratification, and provided scientific evidence for the sustainable housing reform.

Under the background of global financial crisis and transformation of economic growth in China, interactions and coordination between industrialization and urbanization have become an urgent issue that needs to be resolved. Currently, research on this topic only focuses on evaluation of the degree of coordination between the two, and a lot more needs to be done to empirically analysis how to coordinate and optimize the relationship and provide practical approach solutions. In this article, we attempt to investigate this issue with a case study in Shunde, one of the earliest industrialized cities with typical characteristics. It is found that, albeit spectacular industrial growth and performance in the past years, Shunde is facing the challenges such as upgrades needed for industrial structures, lack of driving forces for the growth of service industries, lack of investment options for surplus local capitals, shortage of talent and technology resources, and inadequate domestic demand. All these issues are hindering Shunde's further development and indicating that urban market and urban environment of the city are not well developed yet. We argue that both urbanization and industrialization are the two intrinsic parts of a city's development. Although at the early stage urban growth is dependent on the level of industrial development, which produces and provides goods and services to cater people's demand as well as adjust production and after-production processes, urbanization plays a critical role in enhancing the quality of city's further development. Therefore, we propose a theoretical "point-and-circle" development model to describe and summarize the relationship between industrialization and urbanization: industrialization is the basic starting point of urbanization and is characterized by the process of continuous pursuit of industrial chain extension which inevitably encounters problems and challenges; urbanization works as a ring that helps with the synergy of various elements to provide multiple and diversified development environments and space for industrial development. With regard to the spatial development, the ring includes culture, business and commerce, transportation, living, tourism and recreation, and industrial spaces. Each aspect can be an area of development and contributes to different types of industrial development, whereas the industrialization we generally refer to only emphasizes on the last aspect. Therefore, there is still plenty of room for improvement of the quality of urbanization, which in turn drives the momentum of economic development. In this article, we elaborate theoretical model taking Shunde as an example. It's demonstrated that the model can effectively resolve the issues faced by Shunde from both economic and spatial dimensions. On the economy side, we point out that approach of industrial clustering can be adopted to encourage newly emerged industries. For instance, home electronics and furniture industries have already been following this approach. In order to stimulate the economic potential and expand market, tertiary industry needs to be emphasized to create domestic market. Quite related to this issue, investment channels should be broadened to attract, and make best use of, local capitals. It is also the time for Shunde to more progressively participate in global economy, cooperate and compete with other cities to expand market and improve its technology innovation capability. In the meantime, training and cultivating local talents is also important for Shunde to improve its sustainability. In the spatial dimension, Shunde needs new production space such as incubator for upgrading products and industries. The city should pay attention to social and life space seriously, as it is normally an important factor to the local talent pool and development of new industries. Finally, we put forward a strategy for Shunde to strengthen its cooperation and labor division with other cities.

The economic function of a city is to undertake the tasks in the economies of certain geographical areas and to serve as an economic center. Urban economic functions can be divided into internal and external economic functions. External economic functions are based on leading industries or leading economic sectors, mainly support goods and services for outside areas, and output capital or technologies, whereas internal economic functions provide basic guarantee for production and living activities of the city. Urban internal economic and external economic functions interact with each other and help each other move forward. With the society entering the information age, the producer services, such as finance, science and technology, computer software and information services, have strongly influenced urban industrial and spatial structures, and greatly promoted urban economic functions. Most of the current researches use theoretical analysis to first study the economic functions and then the development of producer services. In this paper, by using social economy, input-output, city population data in 2005 and 2010, based on Input-output model and urban flow model, from two levels of internal and external functions, we analyzed industrial relationships, spatial agglomeration and service products output of producer services, which have greatly improved economic functions of Beijing City. The conclusions are as follows: (1) Economic contribution rate of Beijing's producer service industry is always rising, driving the development of other industries, but at the same time its development is limited by those industries. It also promotes comprehensive benefits of manufacturing industry. Intermediate demand of manufacturing industries and producer services for information, finance, and commercial services increases, which in turn necessitate the upgrade of industrial structure. (2) Financial services, scientific research, information services and business services present an agglomeration in city center, showing a trend to diffuse to suburb areas, with the characteristics of industrial clusters, they have strengthened the function of agglomeration economies of Beijing, leading Beijing to transform from service economy to producer services-oriented economy. (3) Professional level and city flow intensity of producer services are the strongest, and producer services also dominant industries in terms of economic relations with foreign countries. Investment in research, science and technology output, R & D resources has increased significantly, and as a result, the investment has put out a lot of talent and technology as well as labor and capital, with a variety of financial institutions and formation of strong financing scales. (4) Net mix amount and exports of producer services both increased, promoting the output of domestic and international service products in Beijing. The producer services have more advantages in the domestic market, mainly export-oriented. Producer services have higher regional impact on product flow than other industries, and scientific and technical services and financial services industry are the most influential ones. Research on the development of producer services and the economic functions of Beijing City will help understand the productive service industries and their effects on the urban economic growth, agglomeration and diffusion. However, the compositions of urban economic functions include gathering, production, services, innovation and management. Although this paper has touched upon those aspects, detailed studies are required in the future.

Urban social spatial structure is an important content of urban social geography. Macroscopic economic, political and social systems are the foundation of the formation of urban social space; changes of economic, political and social systems contribute to the reconstruction of urban social space. In order to understand long time-scale transformation of the urban social system in China and impact on the changes of urban social spatial structure, this paper depicts the evolutional process of Changchun's social spatial structure in the 20th century. In recent hundred years, Changchun's social system has experienced three periods, including colonialism, socialist planned economy after 1949, and transition period of socialist market economy. Using historical data and statistics from these different periods, based on historical analysis and factor analysis, this paper describes the social spatial types in different periods and reveals evolutional characteristics of the social spatial structure through combined qualitative and quantitative analysis. In colonialism period, affected by Japanese colonial power, four social spatial types emerged, including senior Puppet Manchukuo officers areas, Japanese residential areas, national business areas and China's poor farmers residential areas. In socialist planned economy period, the types of social areas were relatively simple and homogeneous, mainly including salariat areas, intellectual areas and workers areas. In the transition period of socialist market economy, the social spatial types were multiple and heterogeneous. Six social areas were formed including general salariat areas, high-density and crowded old city, concentrated areas of manufacturing workers, areas of high-income population, concentrated areas of migrant population, and areas of agricultural population. In the three different historical stages, Changchun's social space has tripartite different characteristics such as national isolation, units differentiation, and fragmentation, respectively, corresponding to the background of diverse political, economy, and social systems. The external political and military forces were important reasons for national isolation and spatial differentiation in colonialism period. Affected by unit system and functional layout of urban planning, residential spatial differences of employment groups working in different units had become the main reason forsocial spatial differentiation in socialist planned economy period. In transitioning to socialist market economy, due to the development of diversified liberalism market economy, transition of urban function, and motivation of housing market, the polarization and differentiation of social groups have become prominent in terms of wage income, social status and residential location choice. As a result, the differentiation and fragmentation of social space emerged and intensified constantly. In a word, social system and its change always impact urban social spatial space in spite of different political, economic and social systems in the different periods. With the evolution of urban space, the influence would produce spatially overlapping and cumulative effects, which would restructure urban social spatial morphology. In conclusion, this paper mainly reflects the production and reproduction of urban social space in China's modern times with different political, economy, and social systems in the background. In addition, this paper attempts to summarize a theoretical framework of the evolution process and mechanism of urban social spatial structure on the basis of institutional change in China. In the foreseeable future, this theoretical framework will be beneficial to providing a dynamic analysis case for the literature of urban social spatial structure.

Seaport is more an economic system than a geographical space. The functions of modern seaport have changed from marine transportation initially to the node of international logistics center and the hub of global resource allocations now. As a polarized area,when its space is growing, the port exerts a great regional spatial impact on the port-city which is the port's directly linked hinterland, and so the port has become the basic driving force of port-city's spatial remodeling. As a typical example that relied upon a seaport to establish itself as a city and prospered from the seaport, Dalian's urban development has been closely related to the seaport's evolution. During the 100 years from the city's beginning to present, the whole developmental history of Dalian's port and Seaport is more an economic system than a geographical space. The functions of modern seaport have changed from marine transportation initially to the node of international logistics center and the hub of global resource allocations now. As a polarized area,when its space is growing, the port exerts a great regional spatial impact on the port-city which is the port's directly linked hinterland, and so the port has become the basic driving force of port-city's spatial remodeling. As a typical example that relied upon a seaport to establish itself as a city and prospered from the seaport, Dalian's urban development has been closely related to the seaport's evolution. During the 100 years from the city's beginning to present, the whole developmental history of Dalian's port and city boiled down to the process of neoteric and modern port economic development in our country and witnessed the history of port-city relationship. Taking the development of Dalian's port and city as an empirical case, this article puts the geographical spatial relationships of port-city into a multi-dimensional spatial frame, firmly grasps the interactions and transitional relations among "process-mechanism-pattern", and investigates the port evolution's geographical spatial effects at the city's scale. Generation, consolidation and continuous reinforcement of potential energy of the city's location in transportation in urban development, port industrial space growth and morphological evolution, promoting the formation of "Sunshine City" land use pattern, and development of Hub-and-Spoke traffic logistics spatial network with the characteristics of port and shipping harbor, are the four major aspects revealing the mechanism and manifestation of the effects of modern seaport on urban geographical space. This article draws two conclusions. On the one hand, the formation, strengthening and aggrandizement of seaport's potential energy of its location in transportation is the source power of seaport's spatial effect on city. The potential energy makes the port-vicinity belt to be the junction station of production factors, promoting regional growth. In the Supply Chain and information age, port's transformation from location advantage to logistics advantage lays the foundations for production factors' convergence in flow age. Contrary to traditional ports focusing on certain industries and foreign trade, modern seaports continuously strengthens integrated service function of logistics, information and so on. The urban regional spatial effect of modern seaport evolution can be described three aspects. (1) At macroscopic level, port evolution drives port-vicinity industrial spatial development and pushes forward the overall urban morphology evolution, which is the main approach and runs through the whole process of port city development. (2) At microcosmic level, formation of port-city's land-use pattern pushes forward the urban internal structure change and urban function optimization, which is a restriction mechanism. Although with the characteristics of port and shipping harbor are weakening when the harbors are relocating to elsewhere, the circular layer model of land use from single-center city or a new port-vicinity city has relative stability. (3) From the perspectives of time characteristics, logistics center is the principal function of a Third Generation port. Compared to traditional ports, the urban regional spatial effects of a modern seaport clearly have different characteristics. By Hub-and-Spoke space network of traffic and logistics, modern ports drive regionalization and networking of port industries and the evolution of its mother city's space, and finally transform seaport cities to resource allocation hubs of the world market.

Urban metabolism is an organic process in cities which output products, services and waste with the input of resources, energy, and human efforts. As a complex open dissipative system, urban system, including environmental resources, economy, and social development, can be modeled with a range of metabolic processes. Such problems as resources and energy shortage, ecological damage to the environment, human life quality drops, and economic overgrowth, may be due to metabolic disorder in regional and urban development. This article reviewed the progress in the studies of urban metabolism, such as concept perspectives, methods and index system of urban metabolism. Current research field in the urban metabolism can be divided into three parts: macro- regional simulation of urban metabolic systems, metabolic responses of urban land expansions, and micro- scale metabolic measures of communities. As the field of urban metabolism expands, the traditional view of a stationary urban system is giving way to a more dynamic eco-system which includes social and economic facets of the urban systems. Material flow analysis and energy flow analysis are the main research methods. Material flow analysis tracks all of the material, energy and water flows within the urban metabolic systems. Energy flow analysis, especially the Emergy theory, normalizes all products and services to equivalents of one form of energy that enables all of these resources to be compared on a common basis. These two methods have been used to provide additional information to complement economic theory from the viewpoints of resource, energy, and material inputs and outputs, in order to further inform public policy for urban development and sustainability. In addition, other methods include human appropriation of net primary production (HANPP) and multi-scale integrated analysis of societal metabolism (MSIASM). As far as urban metabolic efficiency indicators are concerned, the core is to measure input-output ratio, involving two major categories: indicators of resource input and indicators of output. These two major indicators can be further divided into the indicators of cities' resource consumption, environmental pollution, economic development and social welfare, et al. The integration of them can reflect the overall systematic efficiency and environmental efficiency. Based on in-depth review of urban metabolism development, this article forecasts the trend of application in the urban sustainable metabolism: (1) It is necessary to develop and optimize regional metabolic management policies. Study of urban metabolism is an integral part of monitoring regional environment and provides measures indicative of a region's sustainability. (2) The urban metabolism not only is the basis of an urban daily accounting framework, but also goes a long way towards monitoring urban operations based on the development of the processes in the mathematical models of the urban metabolism. (3) Urban metabolic study helps improve the urban metabolic-oriented green community planning and design. It is possible to reduce environmental impacts by tracking the energy and material flows in urban design. Finally, suggestions on research of urban metabolism are also proposed: focus on the coupling of urban metabolism and industrial development; innovate the mechanism of urban metabolic changes; explore metabolic efficiency differences among different cities; build up a reasonable index system of sustainable metabolism.

Middle-class is an intermediate group with similar social status and social identity, for example, in life style, value orientation, occupational characteristics, and self-perception. Becoming a middle class community (gentrification) in the process in which wealthy families choose to buy and renovate the properties in the areas near city center, resulting in the restoration and upgrading of the run-down urban neighborhoods and the displacement of lower-income people. The middle class often benefit from the improved inner city living environment because of the city government's renovation plans; the city government achieves the increase in revenue growth rate and total amount of growth, thanks to the middle class. It is clear that gentrification is not only a social process in which the middle class emerges at the level of social practice, but also a spatial process in which middle class migrate into the agglomerations in the upgraded inner city areas. This concept has been widely accepted in the western research community. However, controversy about the driving mechanism has long remained. Since the transformation of post-industry society, gentrification has become one of the key research topics on urban issues and spatial planning in the western countries, and as a global phenomenon, has expanded to the new industrialized countries and the emerging markets. In our opinion, gentrification has become a more and more significantly process with mixed characteristics. So it is necessary to discuss the revision that post-industrial cultural capacity of the middle class has made to the driving forces. After a brief overview of this theory, we discussed the impact on the socialization and spatial shift in gentrification again based on Pierre Bourdieu's concept of culture ability, and analyzed the differentiation of culture capacity. By reanalyzing the socialization and spatial shift, followed by a brief review of process and the phenomenon of gentrification, this paper expounds upon the influence of culture on the middle class, the two loops of socialization and spatial process. The author believed that culture ability becomes the most important capital after economic capability and material capital, and revised the double-circle path of gentrification, which separated the socialization and spatial shift from gentrification. So inner city will start to show the characteristics of fragmentation and lose the middle-class. Culture ability also contributes to the spatial shift in a society and socialization of middle-class in a space, and becomes the security of middle-class' reproduction.

Cities in China have undergone unprecedented growth and transformation in the recent years. The research field on urban spatial structure in China expanded rapidly at the same time. To move the research forward during this period of exceptional growth, one of the important tasks is to provide a review or retrospect of the research progress in the past. A statistical analysis of the relevant studies since 1980s indicates the research progress has gone through three time periods: In the first period, from the 1980s to the mid-1990s, the research focused on the introduction of western theories and initial case studies of the cities in China; the second period is from the mid-1990s to the early 2000s, in which the research emphasized empirical studies of the cities; in the third period, since the early 2000s, studies have been focusing on general urban spatial structure pattern and new urban spatial phenomena. Compared to the relevant research elsewhere in the world, six fields need to be highlighted in the future research: general urban spatial structure pattern of the cities in China, new urban spatial phenomena, resource efficient urban spatial expansion, thorough studies on urban spatial structure mechanism, micro scale space, and applications of new research methods.

Urban spatial expansion is the most important manifestation of urbanization process, and urban land– use change is the most direct indicator of urban spatial extension, namely, "spatial urbanization". Along with global urbanization, urban spatial expansion has become a hot field in the research of urban development. Foreign research on urban spatial expansion started to unfold when Quantitative Geography Revolution took place in the 1960s, whereas in China it had a relatively late start in the 1980s. Now China is undergoing rapid urbanization, problems and conflicts in urban space expansion are becoming increasingly prominent. Since 2000, a large number of achievements have been made in this field, and need to be sorted out. Based on the progress of theoretical studies and the change of the content of urban spatial expansion research, this article uses the methods of literature search and comparative analysis to review the research progress. The urban spatial expansion researches are reviewed from five aspects, including expansion types, expansion patterns, dynamic mechanism, simulation and prediction, effects and regulations. Through discussing the different research contents, research methods and research conclusions, and combining classification and comprehensive review of foreign and domestic researches, this review discusses the characteristics and inadequacy of the current research, and suggests future research directions. The trend of urban spatial expansion research in China are summarized in four aspects as follows: (1) future research will become more and more focused on urban spatial simulation and prediction; (2) the research on spatial expansion pattern at the regional scale and in the less developed central and west areas will be strengthened; (3) by taking research experience and methods from other disciplines for reference, we should strengthen the fusion of multidisciplinary methods to be better able to solve the problem of urban spatial expansion; (4) based on the status and environment of urban development research in China, the theory and method of the research need to be innovated, in order to narrow the gap between domestic and international research levels. This review provides a reference for further studies of urban spatial expansion as well as the guidance for a healthy, sound and coordinated development of urban space.

With the accelerated development of globalization and the revolutionary advances of information technology, advanced producer services (APS) have become the main driving force of the region's economic growth and an important source of product innovation, and its positive role in the construction of urban network has gained extensive attention from scholars at home and abroad. By systemically analyzing the changes of the urban network research carrier, it can be found that the layout behavior of the producer services enterprises provides an important breakthrough point for the world's city network research. Meanwhile, due to the advantages of the relational data access, urban network construction from the perspective of producer services industry has become an important frontier of city research in the western countries. On the whole, the close correlation between the producer services aggregation and city level is an important foundation of network construction based on producer services, the acting forces of network construction includes the industry attributes of producer services, location selection of the producer services enterprise, and urban development conditions, such as innovative elements, technical facilities, etc. Through the detailed studies of network construction models, the network features, and the dynamic evolution, it can be found that the layout of producer services industry can be applied to the interpretation of urban network in China under the impact of globalization and informatization. Domestic scholars have recognized its importance, and current researches are focused on introducing the method, rather than being concerned with intrinsic mechanisms and evolution characteristics. As the division of labor in global industries deepens, China no longer just plays a role in manufacturing; the country's producer services will start to cluster in large scales. Domestic research on urban network based on producer services just started, and should be strengthened. Based on practical needs, this paper further proposes directions for future research. With China's more active participation in globalization, the theoretical framework of urban network based on producer services need to be established, the systematic studies of urban network based on producer services at regional level is certainly insufficient, and the driving mechanisms and future trends of the urban network require in-depth investigations.

This paper used the DEA model, analytic hierarchy process and a model for coupling degree to analyze urbanization efficiency, economic development level, and the coupling relationship between the two for the 16 cities in the Yangtze River Delta from 1980 to 2010. As a result, theoretical exploration was conducted and a conceptual model was proposed. The results showed that: (1) During the 30 years of evolution, the economic development level in the Yangtze River Delta has been in a upward trend; regional development reached a balanced stage, and the coupling relationship between urbanization efficiency and economic development level exhibited an overall inverted "U": shaped pattern of "slow rise-sharp rise-slow decline-sharp decline". (2) In different developmental stages, economic development level had different relationship with urbanization efficiency. In a certain period of time, improvement of urbanization efficiency enhanced the regional economic development level, and vice versa. Once both reached a certain level, increase of urbanization efficiency is no longer an important factor to enhancement of the regional economic development level, and, again, vice versa. (3) There is a dynamic coupling relationship between urbanization efficiency and economic development level. Those cities with higher economic development level are the first to be independent of the effect of urbanization efficiency.

With the acceleration of urbanization and the increase of households' energy consumption for heating in winter, the impact of carbon emissions from households' space heating on the environment has become prominent. Although the issue of carbon emissions has received attention from many scholars, microscopic study on the mechanism of carbon emissions is still lacking. The aim of this study is to explore the relationship between lifestyle and carbon emissions from households' space heating. Based on the lifestyle theory and related review articles, the indices of lifestyle factors related to households' space heating are selected, including living space, heating method, length of heating, family size, income, and so on. Through the analysis of the impact of lifestyle factors on carbon emissions, a conceptual model of carbon emissions from urban households' space heating is established, and it shows that heating method, length of heating, living space have direct effects, while family size, income, attitude towards space heating have indirect effects. Based on valid questionnaires from 792 households in a survey in Kaifeng City from December 25, 2011 to January 6, 2012, the features of per capita CO₂ emissions from the 792 households' space heating are analyzed, and the influencing factors are analyzed using multiple regression method. The results are as follows: (1) there is a close relationship between the lifestyle and carbon emissions from households' space heating. The quantity of per capita CO₂ emissions from housholds' space heating varies with family characteristics, heating methods, attitudes towards space heating; (2) for each family lifestyle index has significant effects on per capita CO₂ emissions, among which living space, heating method, length of heating, and family size are the major ones; (3) per capita CO₂ emissions from households' space heating can be regulated by changing to high-efficiency carbon heating methods, controlling the increase of living space, and so on.