Scenario analysis has been widely applied in the realm of urban and regionalplanning. In most of current scenario analysis researches of urban growth, developing policiesare set as the input scenario conditions to generate various urban forms, which can bereferenced by policy makers and urban planners. This paper reverses the line of currentscenario analysis for urban growth, in which the term of form scenario analysis (FSA), aspatial explicit approach, is novelly defined, employing the urban form as the scenariocondition and aiming at identifying whether any policies set can be implemented to realizethe predefined form. If yes, what the detailed policy implications are for the scenario formshould be answered. A constrained cellular automata model (CA) is developed for FSA,which borrows the routine model calibration method of constrained CA using historicalobserved forms from existing literatures. Four planned schemes of Beijing Master Plan 2020for the Beijing Metropolitan Area are analyzed using constrained CA to test FSA approach,and the corresponding required policy parameters are generated, together with policyimplications for the study area. FSA is proved to be suitable for urban planning practice.
With comparative analysis of strengths and weaknesses of current urban expansion simulation models and nonlinearly combining the advantages of best individual-based models, a nonlinear polynomial model of urban spatial expansion has been proposed by using the powerful functions of support vector machine to describe highly complicated nonlinear systems and then to make a better fit for them. The accuracy of the proposed model has been effectively improved by using the parameters of support vector machine optimized with genetic algorithm to reduce the negative influence, exerted by the non-rational design of parameters, on the modeling accuracy of support vector machine. With analyzing the relationship between the error arising from the combined model and all individual-based models, we conclude the ways to improve the accuracy of the nonlinear polynomial model of urban expansion equipped with support vector machine as follows: The first is to improve the accuracy of individual-based models; the second is to enlarge differences between individual models. In the case study of Changsha city, individual-based simulation models of urban spatial expansion constructed by multiple regression model, GM(1,8), BP network and LS-SVM are used to build a linear combination model of urban spatial expansion and a nonlinear combination model of urban spatial expansion equipped with genetic algorithm and support vector machine. A comparison of accuracy of selected models shows that the accuracy of nonlinear polynomial model of urban expansion equipped with genetic algorithm and support vector machine is much higher than any individual-based simulation model, and also higher than the linear combination model, and therefore, an efficient new model of urban expansion is established.
Simulating and restructuring complex non-linear process of urban evolution with cellular automata plays a significant role in urban land use planning and decision-making. By using conventional methods, it is difficult to retrieve reasonable CA transition rules to capture the dynamic process of urban expansion and evolution. Based on kernel principal components analysis approaches (KPCA), non-linear dimension reduction can be executed on spatial variables with multi-collinearity by kernel method projection in the high-dimensional feature space, therefore, a novel CA model based on KPCA with explicit CA parameters is built which can well reflect the nonlinear nature of urbanization. In a geographical modelling framework called as SimUrban developed in a GIS environment, a fast growing area, Jiading District of Shanghai Municipality, is successfully simulated from 1989 to 2006, and the spatial pattern of the urban areas of 2010 is predicted. The simulation results demonstrate that the urban expansion occurred on the fringe areas of urban center and main roads, which reflects the impacts of the first two components extracted from KPCA approaches and highly accords with the actual development. To evaluate the performances of the KPCA-CA model, confusion matrix and area control indexes are used to assess the accuracies of the simulation results. The overall accuracy 80.67% and Kappa coefficient 61.02% illustrate that the simulation results produced by the KPCA-CA model are well matched with the actual urban evolution of Jiading District. Compared with a cellular model based on linear PCA approach, the simulated results generated by the cellular model based on KPCA have higher accuracies.
Since the 1980s Chinese cities have experienced dramatic transformation of its land use system from free allocation toward a leasehold system. Recent literatures have paid attention to spatial features and determinants of land price in transitional Chinese cities, in comparison to its counterparts in advanced market economies. Recently, many scholars have adopted the hedonic model to examine influences of urban spatial structure and local public goods on residential land leasing price. Nonetheless, research on this issue has been limited by the lack of systematic data - especially spatial data - on land leasing parcels as well as other related data sources, and by the limitation of the hedonic model in establishing the complex causal relationship between land price and its determinants. In this paper, we establish a PLS-based structural equation model to quantitatively measure the influences of accessibility to job centers and key local public services on the leasing prices of residential land parcels in transitional urban Beijing. We use Beijing as our case city, and we are particularly interested in four latent variables, i.e. distance to job centers of Beijing, public transportation connectivity, accessibility to public services, and accessibility to amenities, on residential land price during 2004-2008, the period when the land leasing market has largely been established. Based on the analysis, we found that residential land price has obvious relevance with its location to the four latent variables and influential powers of these four latent variables on the residential land price are varied. We believe our research would enrich the existing knowledge of the emerging urban land market in transitional China, and provide information for further land and housing policy making.
Under the background of the rapid urbanization, an obvious limitation of "time lag" is used to analyze urban social spatial structure with the data of national census. The new urban spatial forms emerging in Chinese cities, such as gated community, are changing the former social spatial structure and presenting new urban social spatial characters during the course of urban renewal and sprawl. The data of real estate market can directly reflect the change of housing supply and indirectly forecast the structure and tendency of urban residential differentiation. The essay tries to discuss the course, characters and evolving mechanism of residential differentiation in Nanjing by means of combining investigation on attributes of the 1075 residential communities built during 1998-2008 at macro level with interviews with the residents and analyses of questionnaires in six different and typical communities at micro level. As far as the social spatial characters of residential differentiation in Nanjing concerned, new circle layers have appeared in the urban social space due to the course of residential differentiation under the background of urban renewal in the new period (from 1998 till now); that gated communities grow up greatly has led to the social spatial fragmentation and the privatization of public space; while, the changes of institutional pattern of modern communities and life style have exaggerated the indifference of neighborhood relationship. It examines the common pattern of the driver model of urban residential differentiation in China in the new period, through studying residential differentiation in Nanjing.
Multi-agent system (MAS) is a powerful tool capable of analyzing and simulating complex systems, and has been extensively applied in the regime of social sciences. In this paper we present an agent-based model of residential location (ABMRL) and apply this model to study the dynamic changes of residential location and land price, aiming to explore and simulate the complicated spatial decision-making behaviors in residential location as well as the evolution process of urban residential segregation, which is resulted from interactions among residents and between residents and geographical environment. The ABMRL model consists of agent layer representing various classes of residents and cell automata layer representing geographical environment, which correspond to the two basic elements in man-earth relationship, i.e., human being and natural environment. In this model, psychological concepts were introduced for study of the behaviors of residential location, as it is generally considered that residential relocation is facilitated by internal social and economic pressure and external residential environment. ABMRL model was used to simulate and validate a series of classic urban theories such as residential segregation, concentric urban space structure, gentrification, etc., and to simulate the evolution of residential segregation and dynamic changes in land price in Haizhu District of Guangzhou City, which was taken as a test example for the study.
Through changing ecosystem's internal structure and function, land use/cover change (LUCC) has affected the supply of ecosystem services. Taking Xiamen City in southeastern China as a study area, this paper used a land use intensity model to analyze regional land change processes. Furthermore Xiamen area was divided into three ecosystems: farmland, forests and wetlands, the ecosystem service evaluation model was developed through combining material and value assessment methods; the coupling changes between land systems and ecosystems were used to represent the influences of land use/cover change on natural ecosystems. The results suggested that along with the promotion of land use intensity, the total ecosystem service values increased from 3.48 billion yuan (RMB) in 1987 to 3.90 billion yuan (RMB) in 2007, with supplying and regulating service being main ecosystem service types; land use intensity had positive relationship with supplying and cultural services, while it was negative for regulating and supporting services.
Most cities in the world are concentrated in coastal areas. As a special geographical component of coastal system, island urban spatial expansion is the outcome of interactions between city development and physical environment. This paper takes Xiamen Island, southeastern China, as an example to analyze island urban spatial expansion and its determinants by combining literature analysis of urban development policies, urban overall plans, population growth and industrial development, and geographical information analysis of historical maps and remote sensing images. Firstly, we reviewed the nearly 100 years of the Xiamen city development which can be identified into four periods: the embryo of modern city and early development (1908-1949; administrative boundary expansion and infrastructure development (1950-1979); special economic zone construction and rapid urbanization (1980-2003); changes from island city to bay city development since 2003. The dynamic changes of coastline, island shape, built-up area, transportation, administrative division, and major land use type conversion during the past about 100 years were analyzed individually and the characteristics of the island urban spatial expansion were concluded: expansion from a central point in the early days, expansion along a section of coastline, and expansion from coastline to inner land. Secondly, the potential determinants of island urban spatial expansion were discussed including administrative division adjustment, urban master planning revisions, industrial development, topography factors, coastal land reclamation, transportation expansion, and population growth. Finally, the effects of each potential determinant on island urban spatial expansion were summarized. The island urban spatial expansion is a result of interacted natural and social economic factors. The built-up area expansion is the major driver of island land cover and land use changes. This study can provide a scientific reference for further development of island and coastal regions of China.
Hollowed villages emerged during rural eco-social development transition in China. It caused waste and inefficiency of rural land use and became an obstruction to rural eco-social development. It was of great significance for rational land allocation and new countryside construction to intensify researches on reconstructing hollowed village. Current reconstruction models of hollowed villages usually gave insufficient consideration to peasant's willingness so that some unwanted consequences were caused. In view of the facts, we developed reconstruction models of hollowed villages combining national strategies and peasant's willingness in this paper. Yucheng County of Shandong Province in the Huang-Huai-Hai Plain was chosen as a case to study reconstruction models of hollowed villages. Forty-eight villages and 401 peasant households were sampled to investigate village emptying processes and peasants' willingness for reconstructing hollowed villages. The survey results revealed pervasive problems of small village size, many disused residence sites, decentralized village distribution, short of development planning and public establishment, as well as eagerly willingness of peasants for reconstructing hollowed villages. Three hollowed village reconstruction models, "urbanization leading model", "central village merger model" and "intra-village intensification model", were proposed for different types of hollowed villages by guidelines of establishing new city-countryside relationship and pushing rural space restructuring and resources integration based on peasants' willingness and value judgment of rural development. This study provides a case study of reconstruction models of hollowed villages for other main farming areas such as Northeast China Plain, Middle and Lower Yangtze Valley Plain, and Sichuan Basin.
Along with the advancement of new countryside construction and the launch of coordinating urban-rural strategy, the government and academic circles have paid more attention to the hollowed village problem. As a result, the hollowed village regulation has been turning from a pure academic question to a major action currently taken to expand domestic demand, to push forward the new countryside construction and to realize urban-rural coordination. However, investigation and assessment of hollowed village land consolidation potential is the premise and crux of launching the mission of hollowed village regulation. This paper took 13 typical villages including Xuji of Yucheng City in Shandong Province as examples, and synthetically integrated the advantages and technique methods of multiple disciplines such as geography, 3S technology, land science, and information science, etc. Based on this, it built the technique and method system of hollowed village land consolidation potential investigation and assessment. During the process, we studied from different angles, such as choosing typical hollowed villages, making up current land use classification system on the village scale, designing the schedule and questionnaire for household surveys, as well as the usage and interpretation of high resolution remote sensing images, the classification of hollowed village regulation potential and the corresponding assessment models, and so on. Through the case study of Yucheng City, Shandong Province, the technique and method system built in this paper has proved to be inventive, well-founded, and easy to put into practice. Also, the result of hollowed village potential investigation and assessment was proved to be consistent with the real situation in Yucheng City and good results were gained, which could help to make use of the land consolidation potential of hollowed villages in China.
Suburban districts are imperial for urban development because of its vital roles in catering recreational needs of urban residents and in reshaping urban ecological structure. Beijing, one of the biggest cities in China, has nearly all the recreational land types and also has a long history of recreation development. Thus, the authors, taking Beijing as a study case, conduct research on distribution rules of recreational lands in suburban metropolises. Recreational land types are divided into three groups: public recreational land, commercial recreational land and farm (subsidiary) recreational land. Recreational land database is built up according to this classification. With the aid of GIS, the distribution rules are analyzed in this study. First, there are 161 public recreational land samples, including urban parks, country and forest parks, scenic spots and historic sites. Scenic spots and historic sites are located in outer suburbs, while parks are located along the main roads. Public recreational land has a trend to network structure from line structure. Second, 114 commercial recreational land samples are considered. Transport and water are the main factors in their distribution. Additionally, golf courses, hippodromes and recreational villas are near the center of Beijing, while theme parks, summer resorts and skiing courses are much farther. Third, the data of 222 farm recreational land samples are collected, including farm resorts, traditional country hotels and farm parks. Most of farm recreational lands are near famous scenic spots. In traditional agricultural districts, there would be some farm parks, such as apple parks, cherry parks and watermelon parks. This research aims to find these distribution rules of recreational land in rural districts, which could be applied in urban planning and recreation management. However, the authors point out that there are some issues existing in recreational land distribution of suburban Beijing. Although recreational land follows distance differentiation rules, some commercial recreational sites, such as golf courses and recreational villas are too close to built-up districts and occupy too much space. Most residents can not afford the cost. Furthermore, though there is much land for recreation in suburban Beijing, transport infrastructure and recreational facilities are underdeveloped. Most area of scenic spots and historic sites could not be used for recreation for the above two reasons. Finally, built-up lands have not been restricted in suburbs. Some recreational area is used for apartment building in the name of golf course, skiing parks and farm resorts.
From the perspective of dissipative structure theory, the article considered Qiandao lake tourism destination as a dissipative structure for the support of natural and socio-economic environment, including the attraction subsystem, the infrastructure subsystem, the service subsystem and the subsystem of support. The article tries to reveal the evolution of the destination. From 1959 to 1981, Qiandao lake tourism system was in the embryonic statement when each subsystem had not been formed; the next 12 years experienced the formation process when the subsystems were gradually improved, the overall effects of tourism system began to appear. The period 1995-2000 was the development process, subsystems became mature and there were significant interactions between each subsystem, the overall effect of the system were gradually improved. After 2000, Qiandao lake tourism system was in the better-improving state, and all subsystems are coordinating to impel the most benefit under the whole system. The article analyzed the dynamic mechanism of the evolution and considered the essence of the evolution as a negative entropy input process of the dissipative structure. The nonlinear interaction between the elements of the system was the power of evolution through the heter-organization based on the environment and the control of the government, and the self-organization based on the nonlinear interactions of supply and demand, the man-land relationship, the coordination of regions and the balance of different stakeholders to be realized.
