Changes to urban form and commuting patterns: trends in two Danish city regions

This paper compares indicators of polycentricity in a monocentric (MUR) and a polycentric urban region (PUR) in Denmark at two points in time (1982 and 2002). It describes how population, jobs and commuting indicators of polycentricity develop and interact over time. Both the MUR and the PUR tend towards more balanced development. The increasing size of the main node in the PUR is the only deviation from the general trend. The general tendency towards a more polycentric regional structure was most marked in changing interaction and commuting patterns. Inter-urban commuting increased, while intra-urban commuting decreased, leading to dispersion of commuters and a rapid increase in commuting across the region. Commuting distances were shortest in the polycentric region, but it also had the highest growth rates. In both regions, the balancing trend leads to a dispersal of commuting demand over an increasingly complex web of origins and destination nodes. This tendency compels us to question whether people’s choice of residence is becoming increasingly irrelevant to their place of work. In relation to polycentricity and sustainability, this calls into question the degree to which proximity can be a valuable ‘asset’ in terms of planning sustainable transport outcomes connecting residence, jobs and service.     

Concentration or Dispersion? Location Choice of Commercial Developers in the Portland Metropolitan Area, 2000–2007

This study develops nested logit models to explore the location choice of commercial developers in the Portland metropolitan area, a region that is widely known for its progressive urban growth management. The purposes are to study the dynamics of urban spatial structure from the supply side of the real estate market and to test the capacity of regional governments to manage urban growth by influencing the location choices of developers. The model results indicate that commercial development in the Portland region showed a clear trend of decentralization from its central city. Decentralized commercial developments were not generally dispersed in suburban areas either. Instead, commercial developers tended to locate them in locations within or in close proximity to employment subcenters. Among many control variables tested in the models, availability of vacant land zoned for commercial and industrial purposes proved to be the most important predictor for new commercial development.     

The Slums of Aspen: Immigrants vs. the Environment in America's Eden. Lisa Sun-Hee Park and David Naguib Pellow

In the past decade, Beijing has experienced dramatic spatial restructuring. In this paper, we test whether the conventional monocentric model of urban spatial structure can explain recent developments in Beijing’s land market. Using official land transaction data from 2008 through 2012, we find that (1) for commercial, mixed-use, and residential land parcels, both land prices and development intensities do not decline with distance from the urban center; (2) for industrial land parcels, land prices increase with distance from the urban center. These insignificant and positive land-price gradients defy the predictions of the monocentric model; such results are explained by examining Beijing’s evolution from a monocentric to a polycentric spatial configuration, which has been driven by various urban planning efforts and institutional reforms. Our analysis of post-Olympic Beijing land market dynamics leads to a fresh understanding of the city’s emerging polycentric metropolitan structure.     

Are major canadian city-regions monocentric,polycentric, or dispersed?

Relatively little research has explored spatial structure in modern major Canadian regions. Three common models are monocentricity, polycentricity, and dispersion, but these are not always mutually exclusive in the complex spatial structures of contemporary city-regions. Shifts between these models are discussed in the context of three explanations of economic growth and restructuring: accessibility, municipal competition, and globalization. All three explanations suggest a trend away from monocentricity. While this appears clearly in US cities, disagreement surrounds whether Canadian cities are following the same path. This study uses cross-sectional data from InfoGroup in 2011 to estimate the relative strengths of monocentricity, polycentricity, and dispersion for characterizing eight major regions. Results indicate that elements of each model are evident in all eight study regions, but each tends to dominate in different contexts. When focusing on Montreal, Toronto, and Vancouver, results imply that all three forces which guide spatial structure play a role and that job centers appear to play a particularly important structural role in larger regions.     

城市就业多中心化相关研究进展与述评

就业分布是城市空间结构的核心组成部分。当前,就业多中心化正在成为一个全球现象并主导着城市空间结构研究的范式转变,然而中国对这一主题的研究尚缺乏系统性探讨。论文在梳理中西方相关文献基础上,试图呈现城市就业多中心化的研究进展,以期为国内相关研究提供参考。首先,系统总结国内外城市就业集散与多中心化的地理格局与过程,重点回顾当前研究的共识与争论以及就业中心的生长动态与趋势。其次,从不同理论视角追踪城市就业集散与多中心模式演化的动力机制,关注空间政治经济学视角下就业多中心结构的形成机理,特别是空间规划与管治等制度因素和市场力量的相互作用。最后,从就业多中心化对城市空间结构、城市通勤的影响2个方面总结就业多中心化的空间效应。城市就业多中心模式演化为我们认知城市的空间增长逻辑提供了独特观察窗口,可以为中国城市转型与空间重构相关政策的制定提供决策参考。     

北京都市区人口—就业分布与空间结构演化

本研究应用非参数计量方法,实证刻画北京都市区人口—就业空间分布演化,揭示在快速城市化和城市增长背景下,北京都市区空间结构特征及发展趋势。研究发现,北京都市区人口和就业分布都呈现多中心空间结构。20 世纪80 年代以来,随着人口郊区化,北京都市区人口次中心数量不断增加,并由近郊向远郊扩展,人口分布呈现明显的分散化和多中心化趋势,但人口分散的空间范围还比较有限。与人口的分散化趋势不同,2004-2008 年,北京都市区就业仍呈现向心集聚的趋势,造成远郊就业次中心的影响不断被弱化,都市区空间结构的多中心性有所降低。这说明北京都市区的单中心或强中心结构可能并未从根本上改变,且人口的分散化和就业的向心集聚导致宏观面上人口—就业的空间失衡。北京都市区多中心空间结构的形成,需要强化郊区次中心的集聚能力,同时注重人口—就业的平衡布局,这是未来北京都市区空间结构调整的重点。     

2000―2010年广州人口空间分布变动与多中心城市空间结构演化测度

基于广州市第五次和第六次人口普查中的常住人口数据,运用空间分析法、单中心密度模型和多中心密度模型分析法对广州市人口空间分布和多中心城市空间结构进行研究。结果表明,研究时段内广州人口空间动态变化表现为“内圈层（近郊区）快速增长、外圈层慢速增长、核心圈层（核心区）和外圈低速增长”,核心圈层的人口继续增长并向四周扩散,表明广州人口变动的郊区化现象明显,已呈现多中心特征,由2000年的“1个中心（人民公园）2个次中心（白云区的新景街和海珠区的凤阳街）”演变至2010年的“1个中心（人民公园）4个次中心（白云区的同德街、海珠区的凤阳街、天河区的棠下街和沙河街）”,次中心的人口集聚功能逐渐增强,对城市人口分布影响逐渐增大。     

粤港澳大湾区城市群知识多中心的演化过程与机理

基于1990-2016年“Web of Science”核心合集所收录的科研论文合著数据,借助基尼系数测度属性和功能多中心性的方法,对粤港澳大湾区城市群的知识多中心性及其知识网络的演化进行了研究。结果发现：① 伴随着粤港澳大湾区城市群知识生产总量的持续增长,其多中心性程度呈现出阶段性、阶梯式提升的特征,分别经历了波动、增长和分化的发展阶段,港澳回归后的2000-2010年间是多中心性快速增长的重要阶段。② 粤港澳大湾区城市群在区域、国家和全球尺度上的功能多中心性程度随着尺度增加逐级递减,进一步证实了功能多中心性的尺度规律性;而且发现了多中心在演化中的尺度敏感性,全球尺度上的多中心性会存在不确定的峰值,而区域尺度上的多中心性可能会持续增加。③ 城市群多中心的演化是受制度接近、地理接近和等级接近影响,在研究人员移动、科研单位联动和政府政策推动及其行动主体间的相互作用下实现的,多中心程度的增加有助于推动粤港澳大湾区城市群构建科研协同创新共同体。     

The typology of the American metropolis: monocentricity,polycentricity, or generalized dispersion?

Although the spatial structure of employment in large US metropolitan regions is a well-researched topic, few studies focus on medium-sized and small US metropolitan regions. Consequently, there is no overall typology relating small-to-medium urban form to employment distribution. We address this gap by investigating the spatial structure of employment in 356 metropolitan regions. We conceptualize six typologies based on three categories that have overlapping properties: “monocentricity,” “polycentricity,” and “generalized dispersion.” The study has three main findings. First, the three types of urban form that we identify as “hybrid” outnumber the three “pure” types by almost four to one. Second, job dispersion is a dominant characteristic in almost 70% of all metropolitan statistical areas (MSAs) (including the hybrid types), and polycentricity (56.7% of MSAs) is somewhat more common than monocentricity. Third, there is a strong relationship between population size and density. The population of medium-sized metropolitan areas is generally more dispersed than that of small and large metropolitan areas. Polycentricy emerges mostly in large metropolitan regions, while monocentrity is found in both small and large metropolitan regions.     

中国城市群空间结构的演化与影响因素——基于人口分布的形态单中心—多中心视角

城市群是未来中国城镇化的主要空间载体,研究城市群空间结构的演化特征和影响因素具有重要意义。已有文献较少从形态单中心—多中心视角研究中国城市群空间结构的演化和影响因素,而且通常采用户籍人口而非常住人口测度城市群空间结构,导致测量误差。为解决这个问题,本文采用基于人口普查的常住人口数据进行分析,并运用联合国数据对结果进行佐证。以已有文献采用客观标准界定的13个城市群为样本,使用规模-位序法则测度城市群的形态单中心—多中心程度,探究城市群的空间结构演化趋势和影响因素。结果发现,1980年代以来大多数城市群的空间结构呈现多中心化趋势;人均GDP水平的提高和人口规模的增加是导致城市群空间结构多中心化的主要原因。因此,政府对于空间结构偏多中心的城市群,应强化城市间的交通联系和政策一体化,获取更大的发展红利;对于个别处于单中心化阶段的城市群,政策导向则避免过早地多中心化。