【作者】 单玉红；

【导师】 杜道生； 朱欣焰；

【作者基本信息】 武汉大学 ， 地图学与地理信息系统， 2009， 博士

【摘要】 对城市化现象进行研究,分析城市扩张演化的规律并仿真建模具有指导土地利用规划和城市规划,保证城市土地资源的有效配置和集约利用的重要意义。诸多模型中,多主体模型(Multi Agent System,以下简称MAS)以充分体现“自下而上,由微观主体行为到宏观规律涌现”这一复杂系统演变进化的实质而见长。论文以近十年来在中国城市扩张的进程中占有相当比重的城市住宅用地的增长现象为研究对象,以微观经济学的效用理论和土地生态位理论为基础,通过总结城市居住空间演化过程中各微观主体的行为特征和相互作用,使用GIS技术和情景分析方法构建了城市居住空间演变的多主体情景规划模型,并以武汉市的洪山和武昌两区为实验区对模型的有效性进行了验证。围绕模型的建立和验证,本文做了以下工作。1模型的理论基础与实现机制研究(1)城市扩张的驱动力分析是所有城市建模研究的基础。城市中各种功能活动对生存空间(土地资源)的争夺与自然界中不同生物种群对领地的争夺极其相似,因此相关研究引入生物学中用以解释生物群落之间相互竞争的生态位理论来分析城市土地利用系统中土地利用结构的演变规律,认为不同土地利用类型之间的生态位势差是城市土地利用结构演变的动力,而且这种生态位势差决定于不同土地利用类型的边际效益的比较。本文在以上研究基础上进行扩展,充分考虑城市土地利用的空间特征和微观区位差异,进一步分析土地利用生态位势差的形成原因,针对本文的研究对象给出基于微观区位的城市住宅用地的生态位宽度扩展理论模型,作为建立城市居住空间演化多主体情景模型的理论基础。(2)本文认为,从土地利用的“主客体”关系来看,土地利用的生态位势差归根结底取决于土地利用主体对于土地利用效益的认知方式和程度。对于特定的土地利用客体,不同的土地利用主体会有不同的土地利用方式,城市的扩张也会呈现出不同的情景。由于城市系统的复杂性和人类社会及经济活动的不确定性,建立城市空间扩张模型的目的不在于要实现也不可能实现对于真实情景的100%地复制,而是要抽取城市空间扩张演化的关键因素和一般性规律,分析这些关键因素影响城市居住空间演化的规律。本文分析了三类直接或者间接土地利用主体--城市居民主体、房产开发商和城市政府(微观智能体)的行为对城市居住空间扩张过程的影响,从影响城市居住空间的扩张量和扩张形态两方面分别归纳出主要的情景因素,调整这些情景因素的参数值可以构建城市居住空间发展的不同宏观背景。(3)本文将城市居住空间的扩展过程视为住宅用地资源生态位主体和需求生态位主体两者相互作用的过程。资源生态位主体提供微观区域发展为住宅用地的各种资源条件,由于自然以及社会资源的空间分异特征,城市内部形成住宅用地资源生态位势场。住宅用地资源生态位势场是形成住宅区位差异的充要条件,也是城市居民主体进行理想居住区位选择的依据。使用微观经济学的理论给出城市居民主体、房产开发商和城市政府三类需求生态位主体的目标函数并纳入到模型中,实现对于现实生活中这三类微观主体行为特征的模拟。特别地,论文从消费者效用最大化的概念出发,以城市家庭为单位对其效用组成进行分析,以GIS为技术基础,结合城市自然及社会经济资源的空间分异特征,着重考虑了对于通勤时间成本的实现,对经典的阿朗索模型进行了修正,提出了城市居民主体理想居住区位选择行为的效用模型。(4)建立了模型的实验环境。模型中重点考虑了对于城市住宅用地资源生态位势场各生态位因子的计算记录,以及城市居民主体对于理想居住区位的选择行为子模块的的实现,与以往的研究文献不同,该模块添加了对于通勤时间成本的考虑,对城市居民的选择行为有了更进一步的模拟逼近。一个合理的多主体模型应该遵循“由下而上”的建模机制的,即要充分考虑微观与宏观之间的衔接,论文在模型的实现上,将各宏观情景变量设置为可调整模式,充分考虑情景的多样性,以控制模型的运行过程。2模型实证分析以及主要结论论文以武汉市的洪山和武昌两区为实验区对1998年到2008年实验区城市居住空间扩张状况进行了模拟,对模型的有效性进行了验证,并结合《武汉市2006—2020年城市总体规划》对2008年之后实验区的城市居住空间演变形态进行了基于规定情景的预测,并对各情景下模型的运行结果进行了评价。从模型的运行结果来看,主要有以下结论：(1)从对模型的各宏观参数的调整的运行结果来看,控制城市人口增长速度尤其是机械增长速度是控制城市居住空间扩张速度的关键因素；从对城市居民主体选择偏好的权重值调整的运行结果来看,价格与时间距离的权值调整对于运行结果的影响最大,表明房价与通勤的方便程度一直是城市居民主体在选择理想居住区位时最关注的问题。(2)虽然在现实生活中,城市居民主体看似为被动的购房者,但从运行结果来看,城市居住空间的发展形态实际上会受到城市居民的居住区位意愿的影响,这是住宅市场的供求基本规律和城市扩张自组织机制的体现。随着住宅市场机制的日臻完善成熟,房产开发商会越来越重视消费者的选择偏好和潜在的市场指向；而城市政府也愈加重视公众的选择意愿,注重城市居民福利的整体增长。3论文的主要创新点及研究不足论文的主要创新点和贡献有：(1)城市是以区域自然资源条件为依托的复杂社会经济系统,对城市扩张现象进行研究均不宜绕开其中自然环境或者社会经济环境的任何一方面的问题,本文以GIS技术为依托,以土地市场和住宅市场作为分析主体之间关系的纽带,模拟实现了微观经济学和经济地理学中微观经济主体的“区位选择行为”,在此基础上建立城市居住空间演化的多主体情景模型,初步探索了综合应用自然科学的相关技术和社会经济科学中的相关理论对城市扩张现象进行研究的途径,并取得了有效的成果。(2)本文选择城市居住空间这一特定功能空间的演变为研究对象,使用土地生态位理论结合土地利用的“主客体”关系分析了城市住宅用地的区位效应,研究对象更为微观和深入。(3)使用空间统计和空间分析技术对阿朗索模型进行修正,添加了对于现实情况中城市资源的空间分异特征以及通勤时间成本的考虑,建立了更加实用的城市居民主体选择居住区位的效用模型。(4)在把握主体的行为特征和相互作用关系的基础上,实现了对城市居民主体和住宅开发商两类微观经济行为主体的各自的区位选择行为的解算,更好地表现了城市居住空间系统演化的内在驱动力,建立了更为客观的多主体模型。(5)引入情景分析方法。归纳了影响城市居住空间扩张量和扩张形态的情景因素,模型中通过调整相关情景因素设置不同情景,并对不同情景下模型运行结果进行了分析评价。论文的不足在于自身对于经济学方面理论知识的欠缺,对于城市居住空间演变过程中诸多经济问题把握仍然不够；其次,城市住宅用地的演变与工业用地以及商业用地的演变是紧密联系的,受研究精力的限制,论文只是对住宅市场进行了研究,而没有涉及其他的物业市场。总之,论文尚留有巨大的后续研究空间,模型也处在尝试性研究阶段,总体框架及技术路线有待进一步的修正完善。更多还原

【Abstract】 Studying the phenomenon of urbanization, analyzing the change and extension rules of urban structure and building models to simulate the process of urbanization is very important to direct the urban land scientific and effective planning and using. Among many models, the one based on the theory of Multi-Agents System (MAS) is focused because of its specialty that it can reflect the base evolvement rule "from bottom to top and from micro to macro" of the complicated system fully. Based on the micro-economics and land-use niche theory, paper takes the phenomenon of China cities’ residential land growth which occupy a significant proportion of the expansion of urban space in the past 10 years as the studying role, then uses GIS technology and modeling method of MAS, in the end builds a urban residential space expansion model based on the set scenes. Two districts of Hongshan and Wuchang in Wuhan city are chosen as study districts to prove the effectiveness of the model. By comparing the outcomes of the model, paper analyzed and evaluated the benefits of land resources of the residential land resources development in different scenes. In order to build and rectify the model, paper works as follows.1. The research on theory basis and realization mechanism of the model(1) The research on the driving force mechanism of urban expansion is the basement of urban expansion modeling studies. The competitions of the survival space of every urban functional activities are the one of the land resources, in fact which are very similar with the competitions among the different biological biomes for foods and survival space. So many overseas and internal researches introduce the biological niche theory which is usually used to explain the biological competition behaviors to make clear the change rules in the urban land using system, and concludes that the contrast among the different land use types’niches are just the driving forces. At the same time, from the aspect of the relationship between "land use agent" and "land use object", the contract of land use niches are measured by the value of the marginal utility of different land use type, then how to weigh the value of the marginal utility is decided by the degree of land use agents’recognition of land use utility. Based on this point, the paper puts forward an academic model of the urban residential land niche breadth extension.(2) The extension of the urban residential space is just the interaction processes between the residential land resources niche agents and the residential land requesting niche agents. The residential land resources niche agents afford the resources conditions which are needed for the extension of residential land, while the natural and social resources are asymmetric in the whole urban space, there is a residential land resources niche field which is the prerequisite that residential location differences can come into being and at the same time the bases of the urban residents’behavior of selecting the favourite residential locations. Next, paper defines their roles of the three intelligent residential land requesting niche agents—urban residents, land agent and urban government respectively from the microeconomics point, analyzes their forces and influences on the extension process of urban residential space and summarizes their behavior characteristics function in the end. Especially from the concept of maximizing consumer utilities and by integrating GIS technology and the characteristic of the natural and social resources’asymmetric distribution in urban space, paper analyzes an urban family’s utility components and modifies the typical Alonso model by considering cost of time distance as a core. In the end gets a utility model which is used to describe the utility when urban residents searching the ideal residential location.(3)In the paper, such a point is considered that the motive of building an urban growing model is not getting a copy of the real urban growing situation entirely, but extracting the pivotal factors and common laws of urban growing because of the complexity of the urban itself and the instability of human society and economic activities. So different from the researches ago, the paper uses the method of scenario analysis to extract the pivotal factors which influence the process of urban growth, based on the analysis of these factors’instability, the paper builds some scenarios about the urban residential space extending situation as the micro backgrounds of the urban residential growing multi-agents model.(4) The paper builds an experimental environment of the model is by VC Studio and GIS/RS software platforms. In the model the computation and records of every ecological niche factors and the realization of the function of urban residents’behavior of choosing the ideal residential locations are mainly considered. Different from the former researches, the model adds the consideration of the commuter time cost and simulating the urban resident agents’behavior of selecting the favourite residential locations more realistically. A reasonable multi-agent model should follow the modeling mechanism of "from bottom to top", namely must consider the engagements between the microscopic aspects of the problem and the macroscopic ones fully. In the realization of the model, paper sets some macroscopic variables such as the number of urban residents agents, macro economic anticipated, urban government’s land policies, and so on which can be adjusted in different model scene, so paper can fully consider the multiplicity of scenes to control the model movement process.2 model demonstration analysis and main conclusionsTaking the Hongshan district and the Wuchang district in Wuhan city as the experimental objects, paper simulates the expansion condition of their residential space in the time span from 1998 to 2008 in order to verify the validity of the model. Then according to "Wuhan 2006-2020 Year City Overall Planning", paper forecasts the residential space growing situation after 2008 based on the prescriptive scene, at the same time carries on the appraisal of the outcome of the model on various scenes.Some main conclusions are given as follows from the model’s outputs, (1) In the past ten years, residential space evolution of the researched districts takes the old city transformation and the suburb expansion as the chief features, both are the results of action brought about by land economical ecology niche differences. (2) As compared with the model’s simulating result under the different scene condition, there are always intersection between the reality residential space evolution and the model’s simulating resulte of different scene which means that because of the influence of macroscopic environment, urban government may adjust its land use policy, natural environment protection policy and so on in different periods, this is just one of characteristics of Chinese real estate market. (3) From the model simulating results, urban residents have regarded the rights and interests of themselves more and more, at the same time because of the action of market economy mechanism the real estate developer also pay more attention to the favorite choices of urban residents; and the urban government also take more attention on the public willing and the growth of resident welfare. (4) As showing in the results of the model from different macroscopic parameters, to regulate the urban population rising rate, particularly the population mechanical rising rate is a key factor to control urban residential space’s extending speed; From the results of adjusting the correlative factors when urban resident agents choosing the favorite residential locations, the adjustments of the factors of land base price layers(house price) and cost of time distance have the most influences on the model simulating results, which means house price and traffic convenience are the main factors urban residents concerned about, this also reflects from another side, in the consumer community, the mid and low income crowd still hold comparatively proportion.3. Main research innovation and limitationPaper’s main innovation and the contribution includes:(1) from the internal causes and driving forces of urban residential space’s extending, the paper analyzes every type of microscopic and intelligent agent’s behavior character and interaction each other, and uses related microeconomic concepts and methods to define various agents’behavior character. (2) Considering of the spatial distribution differentiation character of nature and social resources in urban regions, the paper puts forward the concept of urban residential land ecology niche field, while the urban residents’processes of choosing the ideal residential locations are really the processes of choosing the proper residential locations which should match to "the ecology price" of themselves in the urban residential land ecology niche field. (3)The paper improves the classical Alonso model, and builds a new model that can measure the utility which urban residents can get when choosing the ideal residential locations more factually and more roundly. (4) By introducing the scenario analysis method, paper extracts and analyzes the pivotal factors which influence the growing process of urban resident space possibly, then put forwards different scenes, and realizes variable corresponding scene by adjusting the factors and carries on the analysis appraisal to different results.Because of lack of sufficient economic theory and knowledge, the analysis to some economic problems of urban residential space’s successive extending processes are still insufficient. Otherwise there are close interactions among the commercial land’s evolution, industrial land’s evolution and residential land’s evolution, because of the limited research capacity and energy, the paper only consider the residential market but other relatively markets are ignored. In brief, the paper still have huge research space left, the model is also on the attempted research stage, the overall frame and the technical route waits for the further revision consummation.更多还原