Chin. Geogra. Sci. 2008 18(3) 224–234 DOI: 10.1007/s11769-008-0224-0 www.springerlink.com Influencing Factors for Formation of Urban and Rural Spatial Structure in Metropolis Fringe Area —Taking Shuangliu County of Chengdu in China as a Case WANG Kaiyong1, 2, GAO Xiaolu1, CHEN Tian1 (1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; 2. Graduate University of the Chinese Academy of Sciences, Beijing 100049, China) Abstract: With rapid urbanization process, the pace of urban sprawl has been quickened and most metropolises have experienced expansions in leaps and bounds in suburbanization, which has greatly changed the urban and rural spatial structure of the metropolis fringe area. In this paper, Shuangliu County is taken as a case, since it is a typical fringe area of Chengdu Metropolis. Based on Landsat TM images of Chengdu City and Shuangliu County obtained in 1985, 2000 and 2004, characteristics of urban and rural spatial structure in Shuangliu County were analyzed, such as core-periphery spatial structure and some obvious integration trends. Then the influencing factors for the formation of urban and rural spatial structure were identified, including some natural, social, economic and political factors. According to the discussion of this paper, Shuangliu County is undergoing a key transition and reform period. Its formation of urban and rural spatial structure was affected not only by such common factors as the location, natural background, industrial transition, migration, etc., but also by some unique factors such as city planning and policy guidance, which played an important role in accelerating its uneven spatial structure. The understanding of the role of the influencing factors would be useful for carrying out spatial management and development planning of metropolis fringe area. Keywords: urbanization; urban and rural spatial structure; metropolis fringe area; China 1 Introduction It is easier for metropolis fringe area to obtain opportunities and develop rapidly because it is close to metropolitan area. Counties related to the metropolitan statistical areas consist of both urban and rural territory (Isserman, 2005; George and Brian, 2007). In the metropolis fringe area, there is a close linkage between urban and rural areas, and rural lands convert into urban construction lands rapidly. Thus urban and rural spatial structure shows distinct features. What has caused those changes? What countermeasures should we take to optimize and guide urban and rural spatial structure? According to the research on U.S. metropolitan areas, there are many different factors influencing the formation of urban spatial structure. This paper shows its concern on the metropolis fringe area. China is in the process of the rapid urbanization, so it is undergoing abrupt changes in urban and rural spatial structure. According to current rapid urbanization process and the demand of overall planning of city and town, an understanding of the influencing factors for the formation of urban and rural spatial structure in metropolitan fringe area is anticipated in order to better perform management and planning of those areas. After the 1950s, new types of regions different from traditional urban-rural landscapes with urban-rural intermixed function appeared in the developed and developing countries. Some researches on related theories and demonstration were carried out at home and abroad, such as metropolis fringe area (Hall, 1996), edge cities (Keil, 1994), extended metropolitan regions (Ginsburg et al., 1991), urban-rural integration (Jones and Pravin, 1997), peri-urbanization (Webster, 2002), etc. They all demonstrated the characteristics and mechanism of metropolis area, and became a new theoretic frontier and hotspot. Over the past 20 years, spatial differentiation in terms of land use, transportation, housing, environment, Received date: 2007-07-17; accepted date: 2008-04-28 Foundation item: Under the auspices of National Natural Science Foundation of China (No. 40571056) Corresponding author: WANG Kaiyong. E-mail: wangkaiyong2981@sina.com Influencing Factors for Formation of Urban and Rural Spatial Structure in Metropolis Fringe Area and socio-economic aspects has been documented by a number of urban scholars (Landis, 1995; Kahn, 2000). Metropolitan areas in China are still in a drastic era of concentration and decentralization, affected by both international and domestic factors (Zhu et al., 2002). The phenomenon of the urban restructuring and expansion in most Chinese cities has attracted attention of scholars, and many researches were carried out on the dynamics of the formation of urban spatial structure. The driving forces of renewal in central district of a city were thought to result from a combined force of policies, economy and society (Geng, 1999). Economic, social, cultural and political factors were also analyzed in urban restructuring, including the roles that the city planning had played in cities with different development strategies (Zhang, 2001). From the viewpoint of the theory of principal part of benefit, the influence of government, urban economic organization and inhabitants were also discussed in the development of urban spatial structure (Zhang, 1998; Shi, 2004; Yuan and Huang, 2005). All of the above took the urban spatial structure as its research topic, but few have considered the relationship between urban and rural spatial structure, which may lead to the segmentation of the urban and rural areas and coordinated regional development. Therefore, we should take urban and rural areas as an integrated entity and analyze them comprehensively. With the economic development and social advancement, the communications between urban and rural areas are well developed and landscape edge becomes more and more vague (Shi and He, 1997). Urbanization is the response to economic and social development of China in the future and rural-urban integrated development is a strategic theme of urbanization (Shao et al., 2005). Although spatial structure characteristic and its negative impact have been documented extensively in the literature, the issues of influencing factors on urban and rural spatial structure and subsequent policies for preventing or ameliorating it in metropolis fringe area have not been clearly discussed. Hence, this paper investigates the characteristics of spatial differentiation from a case study of metropolis fringe area—Shuangliu County, which is a typical metropolis fringe area of Chengdu, and tries to clarify some concrete influencing factors on the formation of urban and rural spatial structure. This paper seeks to contribute specifically to the understanding of the role of influencing factors and more generally 225 to the knowledge of spatial management and development planning in metropolis fringe area. 2 Study Area and Methods 2.1 Study area This paper takes Shuangliu County of Sichuan Province as a study case. Chengdu, the capital of Sichuan Province, is an important megalopolis in Southwest China. Shuangliu County, a suburban county of Chengdu, is located in the south and adjacent to the central district of Chengdu City, where there are county seat, Chengdu international airport and southwest airport economic development zone in Shuangliu County, all of which manifest its excellent location (Fig. 1). Shuangliu County has a total population of 928,100 with 21 towns and three communities under its jurisdiction, covering a total area of 1067km2. The economic development in Shuangliu County has been increasing fast: in 2006, the total regional value of production reached 22.78×109 yuan (RMB); per capita GDP of the entire city exceeded US$2500; the revenue was 2.09×109 yuan; and the total sum of retail sales of consuming goods was 5.5×109 yuan. The basic competence ranked the 43rd among the “Top China 100 Counties” in 2006. Moreover, it has achieved the eleventh consecutively leading the top ten most powerful counties in Sichuan Province according to the comprehensive evaluation of economic capacity. With rapid urbanization process, it is easy to develop firstly in metropolis fringe area, which is just in the transitional period experiencing sharp changes in social and economic spatial structure. Under this background, as it is in the suburbs of Chengdu Metropolis, Shuangliu County is affected greatly by Chengdu because of the close connections in economic and social development between them. On the other hand, Chengdu and Shuangliu governments are carrying out urban and rural integrated development strategy and “Three Convergences” policy (it means population converge into the city and town; land converges into the minor family; industry converges into development zone), which accelerate the fundamental changes of urban and rural spatial structure and ways of production and living. Taking Shuangliu County as a case, this paper studies and discusses how these factors such as natural, social, economic and political factors influence the changes of urban and rural spatial structure. 226 WANG Kaiyong, GAO Xiaolu, CHEN Tian Fig. 1 Location of Shuangliu County in Chengdu Metropolis 2.2 Data collection and analysis methods The data of land use in the three periods were obtained from the land use survey maps of 1985, 2000 and 2004 at a scale of 1︰10,000, the topographic maps of 2000 at a scale of 1︰10,000, and the TM images of 1985 and 2000. The data of population and socio-economic statistics were obtained from the statistical materials, as well as the unpublished statistical data from Shuangliu government. To well master the actual conditions, investigation and interviews were carried out from December 2005 to January 2006. The research on urban structure was established by gray multi-objective programming approach (Xu et al., 2007; Shao et al., 2005). Spatial data processing and analysis of the transformation of land use were carried out by ArcGIS (ESRI GIS software), while statistical analysis of demographic and other data were conducted by using SPSS10.0 for windows and ArcGIS 9.0. 3 Characteristics of Urban and Rural Spatial Structure in Shuangliu County 3.1 Spatial expansion There is a close relationship between Chengdu and Shuangliu. After the completion of Shuangliu international airport in 1990, Chengdu began to expand to the south rapidly. The General Master Plan of Chengdu made in 1996 pointed out that the development of north and west of the central city should be restricted and the city should be guided to develop eastward and southward. Thus, the main development of Chengdu has been converted successfully by implementing this planning. The Chengdu municipal government has carried out the “Five roads and one bridge” projects, which enhanced the trend of development in east and south directions. Through the economic communications between the central Chengdu Metropolis and Shuangliu County, Shuangliu is urbanized, especially in the northern part of the county (Fig. 2). 3.2 Urban and rural population structure Taking advantage of its location, Shuangliu County has a solid economic foundation. The total population has grown continuously since 1997, especially the rate of increase was large after 2002. In terms of the increase of population structure, natural increase has been at a relatively low level while mechanical increase was obvious after 2002 and has occupied a dominant position (Fig. 3). With the transfer and aggregation of industries and population in Shuangliu, it can be anticipated that future population growth will also give priority to immigration increase. The main sources of immigrants may include Influencing Factors for Formation of Urban and Rural Spatial Structure in Metropolis Fringe Area 227 Fig. 2 Expansion and evolution of land in Chengdu City and Shuangliu County the eastern and western parts where hilly and mountainous areas predominate, the population density is lower, all below 500 person/km2. Viewed from the population engaged in three industries, the proportion of agricultural labor forces remains very high and that of secondary and tertiary industries is low and develops slowly. Therefore, it is difficult for industries to provide more jobs for migrant workers. Fig. 3 Sketch map of population increase in Shuangliu County from 1997 to 2005 the labor forces immigrating to the southwest airport economic development zone, the emigrants from the central district of Chengdu, the immigrants absorbed by large scale residential areas such as Dongsheng and Huayang as well as teachers and students in colleges and universities. Up to the end of 2005, the total population have reached 920,000 in Shuangliu County. From the distribution map of population density in every town in Shuangliu County in 2005 (Fig. 4), the general characteristics of population spatial distribution were that the highest population density is in the northern part, the second in the central part, and the lower in the eastern and western parts. The highest density area mainly concentrates in the northern subdivisions, especially in Dongsheng Town which is the seat of the county, southwest airport economic development zone and Zhonghe and Huayang towns, where the population density has all reached 2000 person/km2. In the peripheries of these core growth areas and the central plain area, the population density is rather high. However, in 3.3 Land use change The land use change in Shuangliu County is shown in Fig. 5. From 1985 to 2004, great changes took place throughout the county and the construction land was unevenly distributed. Shuangliu County has paid more attention to the northern subdivision, where the construction and development aggregated, and land expansion was fast and most concentrated. From the viewpoint of economic statistical indicators, the overall economic strength of Shuangliu County is so tremendous that it has been one of “China Top 100 Counties” for many years. However, the development level of regional economy is imbalanced. The northern subdivisions develop rapidly, and the economic strength of other towns is weak with the primary industry as the major trade. So the stronger counties and weaker towns are the prominent characteristics of development of Shuangliu. From the map of land use in every town in Shuangliu in 2005, the similar characteristics are also shown (Fig. 6). The proportion of construction land is higher and that of farmland is lower in the northern subdivisions, whereas farmland plays the leading role in other towns. In the eastern mountainous area, the proportion of unused land is higher but it is difficult to develop and utilize due to severe relief. 228 WANG Kaiyong, GAO Xiaolu, CHEN Tian Fig. 4 Distribution of population density in every town in Shuangliu County Fig. 5 Distribution and evolution of construction land in Shuangliu County in 1985, 2000 and 2004 Influencing Factors for Formation of Urban and Rural Spatial Structure in Metropolis Fringe Area 229 Fig. 6 Core-periphery spatial distribution of construction land proportion and investment of unit area land in every town in Shuangliu County 3.4 Spatial structure The development level of Shuangliu County has always been uneven and imbalanced, and the trend becomes more and more obvious. Through the analysis of the map of the spatial distribution of construction land proportion in every town and the distribution of investment of unit area land in every town across Shuangliu County (Fig. 6), we can find that the social and economic development presents a core-periphery spatial structure. The spatial structure characteristic of circle expansion is formed under the influence of distance and location. The inner circle includes towns of Dongsheng, Huayang, Wenxing, Baijia, Jiujiang, Shengli and Zhonghe, where the proportion of construction land is relatively high, being the main construction area of Shuangliu County. The second circle surrounds the inner circle, including Wan’an, Zhengxing, Gongxing, Huangjia, Huangshui, Pengzhen, Jinqiao, Yong’an and Jitian towns, where the proportion of construction land is lower than that of the inner circle. They are also mainly affected by the northern subdivisions, but with an insignificant leading role of farmland. The third circle is located in the outer circle and mountainous area, including towns of Xinxing, Baisha, Taiping, Xinglong, Hejiang, Yongxing, Huanglongxi, Sanxing, Jiancha and Dalin, where the proportion of agricultural land is higher in land use structure and farming dominates local economic activities. From the viewpoint of economic benefit and residents’ standard of living, the uneven regional development in the whole county shows similar characteristics: places with per capita GDP over 20,000 yuan in the county are all located in the northern towns while those with that less than 6000 yuan of the county are concentrated in the southeastern part of the county. The urban-rural differences in the construction of fundamental service infrastructure and social service infrastructure have limited the economic connection and urbanization process. 3.5 Land use conditions Nowadays the land use mode in Shuangliu County for urban construction is extensive, indicating low land use intensity and output efficiency. From Table 1 we can find that per capita cultivated land in Shuangliu is lower than that of Sichuan Province but is higher than that of Chengdu, reflecting an inverse relationship between population density and agricultural land. However, per capita available construction land is higher than the average level of Sichuan Province or Chengdu. In view of the land use for rural residential house construction, the area of homestead per capita is also higher than the average level of Sichuan Province or Chengdu. The extensive urban land use directly led to the occupation of rural land WANG Kaiyong, GAO Xiaolu, CHEN Tian 230 resource, and the non-intensive utilization of rural land will also bind up rational urban development in the future. Table 1 Comparison of average level of land use intensity (m2/person) Per capita construction land Per capita cultivated land Per capita house site Sichuan Province Chengdu City 180.04 176.43 701.34 400.84 154.48 160.19 Shuangliu County 254.45 543.82 187.21 Region From the viewpoint of per unit land output comparison in every district and county of Chengdu, land use efficiency of Shuangliu County was the lowest among the suburbs in 2005 (Fig. 7), which was mainly due to extensive land use. This kind of extensive urban land use mode with outer urban expansion has led to direct encroachment on rural land resources, especially on cultivated land and intensification of the inverse relationship between population and agricultural land, thus resulting in the relative shortage of land supply. Therefore, the land cannot meet the need of social and economic development in the future. Consequently, more agricultural land may be encroached for further development in the years to come. Fig. 7 Comparison of per unit land output efficiency in every district and county of Chengdu in 2005 4 Discussion There are many factors affecting the formation of urban and rural spatial structure, such as natural factors, social factors, economic factors, political factors and historical ones. As a case study, Shuangliu County has not only the above-mentioned common factors that exert a deep influence on the formation of its urban and rural spatial structure, but also some special factors that play a great role. For example, the location conditions close to Chengdu metropolis fringe area and the location of Chengdu international airport make Shuangliu County have some advantages in economic development, and the development ideas of “Three Convergences” accelerate the urban and rural integrated development. But this integration is limited, all of the influence factors worked together to form the imbalanced core-periphery spatial structure. In general, location condition and natural background afford a possibility of development, and urban and rural planning has some manipulative contents such as functional zoning and transportation system planning, which forms the framework of urban and rural spatial structure (Fig. 8). Constructions under the planning accelerated Influencing Factors for Formation of Urban and Rural Spatial Structure in Metropolis Fringe Area spatial agglomeration and dispersion of productive factors, and caused land development and expansion, transition of industries and population migration. And government guidance such as trade and investment attraction and “three convergences” policy also accelerate 231 imbalanced development of urban and rural spatial structure. In a word, every factor has exerted different influences on the formation of urban and rural spatial structure, and they are intermixed and interacted. Fig. 8 Influence of different factors on urban and rural spatial structure 4.1 Location and natural background Shuangliu County is adjacent to Chengdu Metropolis, of which Dongsheng and Huayang towns have become the satellite cities and sub-centers. Chengdu international airport is located in Shuangliu County. This excellent location has some important influences on the spatial structure as follows: first, it accelerated the economic and trade communication between Chengdu and Shuangliu, and attracted the industrial transfer and investment of big enterprises from the inside and outside of the province. Secondly, depending on the international airport, the economic development zone of the airport in the southwest was established, which has become a regional growth pole of Shuangliu County. Thirdly, taking advantage of favorable development groundwork and predominant location condition, emphasis has been put on the real estate. For example, Huayang Town, which is in the northern part of Shuangliu, has upstanding location condition and residential surroundings. So it has attracted plenty of investment of real estate corporations and has become an important new town and residential area of Chengdu. Therefore, the location condition of being adjacent to metropolis affords convenient condi- tion for rapid development of Shuangliu. Affected by the law of the distance decay rule and accessibility, the northern part of Shuangliu developed first and formed the imbalanced regional development configuration, so location has become a fundamental factor which affords the possibility of development. On the other hand, the natural condition, especially its undulating of terrain obstructed the exchange extent of economic flow (such as investment and economic cooperation) between urban and rural areas. From the viewpoint of regional distribution, Shuangliu is located in the southeast of Chengdu Plain, and lies to Longquan Mountain in the southeast and Muma Mountain in the southwest, only with the plain areas in the northwestern and central parts. So the terrain is complex in Shuangliu, including hills and plain. At the same time, it also decides the land use mode and development order. The natural condition of Shuangliu County led to social and economic imbalance of plain town and mountainous town within Shuangliu County obviously. In a word, natural background results in the development possibility of different regions, and location condition affords an elementary configuration of the formation of urban and 232 WANG Kaiyong, GAO Xiaolu, CHEN Tian rural spatial structure. 4.2 City planning and governmental guidance The formation of urban and rural spatial structure has a close relationship with city planning and government guidence and regulation. With rapid urbanization process, land expansion grows like a weed, so it is necessary to carry out land use planning and city planning to control the disorder and overspread expansion, whose significance and urgency are more obvious in metropolis fringe area. Due to adjacency to metropolis, Shuangliu County is easy to gain investment, technology and industry transfer. However, in order to realize ideal economic connection between central area and fringe area, in accordance with the demand of scientific development ideas, it is important to carry out general land use planning and city planning to speed up integration of urban and rural areas, which can plan a rational development space to avoid developing out of order. In fact, the entire scope of Shuangliu has been brought into the metropolis area in the new general city planning of Chengdu carried out in 1996, which confirmed Dongsheng and Huayang towns as the main development area of Chengdu in the future. In conclusion, the development direction of city planning determines the population and industry converging area in the future, so city planning plays an important role in the formation of urban and rural spatial structure. On the other hand, institutional arrangement and regional policy at different levels (national, provincial and urban level) have significant impact on the formation of urban and rural spatial structure. For example, coordinated development of the urban and rural areas and coordinated regional development were put forward by the central government of China in 2003; “The No. 1 Document of the Central Committee of the Communist Party of China” in 2004 focused on building a new socialist countryside. All of those embody the transit of concept of development in the whole society, and urban and rural harmonious development has been emphasized. Under this background, the “Three Convergences” policy was carried out by Chengdu and Shuangliu governments, which changed urban and rural spatial structure greatly and accelerated the imbalanced development of urban and rural spatial structure. As the population aggregation to the town and the city, there have come some social problems yet to be solved. For example, as the employment of peasants who lose their land and immigrate to city and town were not arranged wholly, so though they lived in the city, they did not have a stable income source, and they could not afford the social assurance, which poses a threat to the stability of the society. 4.3 Industrial transition and market regulation Industrial layout is the key support of urban and rural economic development. Industrial spatial transition and reorganization are the main driving forces of the formation of urban and rural spatial structure. Industrial transition means the increase of ingoing area economic gross and opportunity of obtaining employment, thus industrial transition brought population into convergence, which becomes the main driving force for forming urban and rural spatial structure. As for Shuangliu County, there are excellent development groundwork and location conditions in the northern subdivision, plus development of southwest airport economic development zone, which promoted the transition of some industries of Chengdu and big corporations’ investment from Sichuan Province and abroad. By means of convenient transportation and beautiful surroundings, Huayang Town has attracted a lot of investment from real estate enterprises, which has become a new town and residential area of Chengdu Metropolis. Of course, those industrial transitions pursue more profits and save production cost mainly, so the guides of regulation of market economy afford an institutional guarantee for industrial transition. Due to the adjustment function of market mechanism, urban agriculture with high profit developed quickly within Shuangliu County, and vegetables, fruits and flower industries are well developed to supply the metropolitan market. 4.4 Land use change The expansion of urban economy and development of urbanization need more lands for non-agricultural purposes. When the central district is too crowded to be further developed, the city will expand to the outer space where the distance is short and is suitable for development. Shuangliu County is one of the important components of Chengdu-Chongqing metropolitan belt and a key node on the axis of Leshan-Chengdu-Mianyang development zone, so its preponderant location affords possibility to develop first. On the other hand, Influencing Factors for Formation of Urban and Rural Spatial Structure in Metropolis Fringe Area the lower land price and enough land supply meet the demand for the construction land expansion of Chengdu. In terms of land use change of Chengdu in recent years, the belt from Chengdu to Shuangliu is the most rapid axis of urban land development. From 2000 to 2005, construction land in Shuangliu increased at an annual rate of 5%. Expansion and change of land use has become obvious token and carrier for the formation of urban and rural spatial structure. 4.5 Population migration and spatial transfer Expansion of construction land achieved the structural transform of landscape setup, and rural population immigrating to town and city achieved real urbanization. The change of population density and living mode are the main bases for dividing cities and the countryside. In a word, the spatial migration of population is the means for realizing the formation of urban and rural spatial structure. The total population was 928,100 in Shuangliu County at the end of 2006, and most of the people are engaged in agricultural production. The rural economic structure has been gradually adjusted and plenty of surplus labor forces are emerging. Meanwhile, with the execution of the “Three Convergences” policy and development of economic development zone of the airport in the southwest, quite a number of people have moved into the northern subdivision, and accelerated the imbalanced situation of urban and rural spatial structure. All kinds of product and living activities must be occurred in some space, so urban government should afford enough activity space and material supports for them. Urbanization strategy should be carried out to facilitate the three agriculture-related aspects (rural area, farmer and agriculture), first of which is how to guide agricultural population to become urban citizens and how to improve the standard of living of farmers. The trend and source of population increase are the important factors in the social and economic construction in the future. Population and industrial policies should be formulated according to the demand of planning and industrial development, which can guide spatial transition and convergence of population and form rational and orderly urban and rural spatial structure. 5 Conclusions (1) With rapid urbanization progress, great changes have 233 taken place in urban and rural spatial structure. Especially in metropolis fringe area, it is attracted and influenced by metropolis intensively. The linkage between urban and rural areas is close, and expansion speed of urban construction land is fast. The change of urban and rural economic structure and landscape setup is quickly and obviously, so the “core-periphery” spatial structure was formed in Shuangliu County. (2) Shuangliu County is a typical fringe area of Chengdu Metropolis, where many driving forces worked together to form the shape of imbalanced core-periphery spatial structure. The formation of such a kind of structure is not only because of the expansion of Chengdu Metropolis, but also because of the government policy such as “Three Convergences” which accelerated the imbalanced spatial structure. (3) It is better to accelerate urban and rural integrated development in the metropolis fringe area which not only has excellent location and tremendous economic strength, but also needs a rational step and scale. (4) The location and natural background influence the basic configuration of the formation of urban and rural spatial structure; city planning and governmental guidance are the direct reasons for the formation of urban and rural spatial structure, which affect urban and rural spatial structure directly and form a new spatial conformation; industrial transition and market regulation are the fundamental reasons for the formation of urban and rural spatial structure, which caused land use change. The population migration and spatial transfer are the means for realizing the formation of urban and rural spatial structure. Just as this paper discussed above, the driving forces for forming the urban and rural spatial structure are synthetic and complicated, thus in-depth research is needed to grasp the characteristics and influencing factors precisely, which can guide the urban and rural spatial structure to develop orderly. Some influencing factors worked together to form urban and rural spatial structure. However, the mechanism and effect intensity of these influencing factors need to be further studied. References Ginsburg N, Koppe B, McGee T G, 1991. The Extended Metropolis: Settlement Transition in Asia. Honolulu: University of Hawaii Press. 234 WANG Kaiyong, GAO Xiaolu, CHEN Tian Geng Huizhi, 1999. The discussion on dynamic mechanism of renew of urban central area. City Planning Review, (3): 27–32. (in Chinese) George W H, Brian J O, 2007. The growth impact of the metropolitan statistical area designation. The Annals of Regional Science, 42: 307–319. DOI: 10.1007/s00168-007-0147-1 Hall P, 1996. Revisiting the non-place urban realm: have we come full circle? International Planning Studies, (3): 7–151. Isserman A M, 2005. In the national interest: Defining rural and urban correctly in research and public policy. International Regional Science Review, 28(4): 465–499. Jones GW, Pravin V, 1997. Urbanization in Large Developing Countries: China, Indonesia, Brazil, and India. Oxford: Clarendon Press. Kahn E M, 2000. The environmental impact of suburbanization. Journal of Policy Analysis and Management, 19(4): 569–586. Keil R, 1994. Edge cities in Western Europe (Editorial). Environment and Planning D, 12(2): 131–137. Landis J D, 1995. Improving land use futures: Applying the California urban future model. Journal of the American Planning Association, 61(4): 438–457. Shao Jing’an, Wei Chaofu, Xie Deti, 2005. Mountain land use planning of metropolitan suburbs: The case of the Jinyun Mountain and its surrounding area, Chongqing, China. Journal of Mountain Science, 2(2): 116–128. Shi Song, 2004. Analyses of the driving mechanism of the evolvement of urban spatial structure. City Planning Review, (1): 50–52. (in Chinese) Shi Yishao, He Shujin, 1997. The discussion on urban-rural integration. City Planning, (5): 13–19. (in Chinese) Webster D, 2002. On the edge: Shaping the future of peri-urban East Asia. Institute of International Studies. Stanford, California: Stanford University, USA. Xu Jiangang, Liao Banggu, Shen Qing et al., 2007. Urban spatial restructuring in transitional economy: Changing land use patterns in Shanghai. Chinese Geographical Science, 17(1): 19–27. DOI: 10.1007/s11769-007-0019-8 Yuan Lili, Huang Luyun, 2005. Analyses of the driving mechanism of the evolvement of urban land spatial structure. Urban Studies, (1): 64–65. (in Chinese) Zhang Bing, 1998. Discussion on the Practicability of City Planning. Beijing: Renmin University of China Press. (in Chinese) Zhang Tingwei, 2001. The urban restructure of Chinese cities in 1990s and its dynamic mechanism. City Planning Review, (7): 7–14. (in Chinese) Zhu Xigang, Zhang Jingxiang, Chen Hu, 2002. A case study on concentration and decentralization: Behavior and dynamic mechanism of spatial evolution in metropolitan area, Nanjing, China. Chinese Geographical Science, 12(3): 212–217. DOI: 10.1007/s11769-002-0004-1