Dark side of the planet: hidden dimensions of urban agglomeration

ABSTRACT

This intervention probes the hidden, political dimensions of planetary urbanization. Drawing on political theory, it approaches its analysis through the analytic of ‘the political,’ the dimension in which antagonism performs a constitutive function in the social order. In doing so the intervention throws into relief the ways in which group-based differentiation, conflict, and exclusion establish the conditions of possibility for ongoing transformations of urban agglomeration. It then develops a case for further exploring intersections of the political and capitalist agglomeration to generate new knowledge about current mutations in urban economies of space.     

The geomorphology of planetary calderas

Satellite-derived observations of the geomorphology of calderas on Earth, Mars and Venus can be used to learn more about shield volcanoes. Examples of terrestrial basaltic volcanoes from the Galapagos Islands, Hawaii, and the Comoro Islands show how these volcanoes contrast with examples found on Mars and Venus. Caldera structure, degree of infilling, and the location of vents on the flanks are used to interpret each volcano's recent history. The geometry of the caldera floor can be used to infer some of the characteristics of the magma storage system, and the orientation of the deep magma conduits. The formation of benches within the caldera and the effects of the caldera on the distribution of flank eruptions are considered, and it is evident that most calderas on the planets are/were dynamic features. Presently, deep calderas, with evidence of overflowing lavas and ponded lavas high in the caldera wall, show that these calderas were once shallow. Similarly, shallow calderas filled with ponded lavas are evidence that they were once deeper. It is probably a mistake, therefore, to place great significance on caldera depth with regard to the position, shape, or size of subsurface plumbing.     

Planetary urbanization: new perspectives on the debate

ABSTRACT

This essay is the introduction to the forum on Planetary Urbanization for the Debates and Interventions section     

Uneven urban metabolisms: toward an integrative (ex)urban political ecology of sustainability in and around the city

ABSTRACT

Expanding cities present a sustainability challenge, as the uneven proliferation of hybrid landscape types becomes a major feature of 21st century urbanization. To fully address this challenge, scholars must consider the broad range of land uses that being produced beyond the urban core and how land use patterns in one location may be tied to patterns in other locations. Diverse threads within political ecology provide useful insights into the dynamics that produce uneven urbanization. Specifically, urban political ecology (UPE) details how economic power influences the development decision-making that proliferate urban forms, patterns of uneven access, and modes of decision-making, frequently viewing resource extraction and development through the urban metabolism lens. The political ecology of exurbia, or, perhaps, an exurban political ecology (ExPE), examines the symbolic role nature and the rural have played in conservation and development efforts that produce social, economic, and environmental conflicts. While UPE approaches tend to privilege macroscale dynamics, ExPE emphasizes the role of landowners, managers, and other actors in struggles over the production of exurban space, including through decision-making institutions and within the context of broader political economic forces. Three case studies illustrate the strengths and weaknesses of these approaches, demonstrating the benefits for and giving suggestions on how to integrate their insights into urban sustainability research. Integrated political ecology approaches demonstrate how political-economic processes at a variety of scales produce diverse local sustainability responses.     

The politics of the possible: Making urban life in Phnom Penh

Phnom Penh, 're-entering' urban history as it did just some three decades ago becomes an important arena in which to focus on the intensifying contestation of rights, practices and development trajectories related to city making. Far from being comprehensively marginalized by emerging urban economies, residents with limited economic means, through their configurations of space, social relations and infrastructure continuously attempt to construct the conditions that enable the city to act as a flexible resource for the viable organization of their everyday lives. These issues are taken up in an analysis of some of the ways in which residents of a large low income housing tract, popularly dubbed 'Building', in the Bassac River neighbourhood collaborate to maximize their access to resources and opportunity.     

1988—2018年中国城市实体地域与行政地域用地扩张对比

城市边界是城市演化认知和城市规划决策的空间依据。中国不少研究实践将地级市等行政地域范围视为城市,与物理上主要由连续人造不透水面构成的城市实体地域相比,存在较大的空间边界差异。然而,鲜有研究定量分析“实体”视角下长时间序列的城市用地演化,特别是对实体和行政两种统计单元视角下的城市扩张差异缺乏系统认识。本文基于30 m空间分辨率的多源遥感产品识别了1988—2018年8期的城市实体地域边界,分析其用地扩张过程,进一步与行政地域相对比,系统识别了两种统计视角下城市用地扩张的认知差异和空间模式。主要结论为：① 1988—2018年间,中国面积5 km²以上的城市实体地域单元数量增长了378%,以华东和华中地区的增长最为显著;城市实体地域中,88%为独立增长型,分布广泛但面积大都小于50 km²;12%为空间聚合型,主要分布在发达地区,面积普遍较大。② 相比行政地域,城市实体地域的位序规模更符合幂律分布,其Zipf指数30年来逐渐上升趋向于1,城镇体系发展愈发均衡;相比城市实体地域,行政地域单元在平原地区的城市扩张面积普遍偏高,在沿海地区的城市扩张强度普遍偏低。③ 和城市实体地域单元在拓扑关系上无法一一匹配的1327个行政单元大多分布在人口密集或发达的平原地区;结合实体和行政边界识别了“跨政区同城化”和“政区内集群化”两种扩张模式,前者多发生在省会区域,后者主要分布在华北平原,两者反映了城市化的空间重构。本文研究结果有助于深化中国土地城镇化时空过程的认识,并可对土地资源的科学配置、统一协调及行政区划的优化整合提供空间依据。     

1978年以来中国城市地理研究进展

以国内出版的专著和重要学术期刊发表的学术论文为资料基础,运用文献计量学方法,对1978年改革开放30多年来中国城市地理的研究进展进行了总结。研究发现：中国城市地理研究总体上日益繁荣,研究内容不断拓展和深化,研究方法逐步走向“科学化”和“规范化”,研究的空间尺度总体上“由大向小”转变,研究视角向多样化转变;国家政策和城市热点问题对研究内容具有重要影响,西方理论和流派对研究视角具有重要影响;基础研究与应用研究并重是重要特色,城市化与城市体系是重要的研究主题。建议在未来的研究中培养全球化视野,批判性地引进西方理论,加强理论创新、科学规范、跨学科交叉与新方法引进。     

On feminism and feminist allies in knowledge production in urban geography

In this response to Ananya Roy’s paper, I ask: who are the allies of feminist knowledge production about the urban? To explore this question, I specifically ask what feminist scholars may find of use in two books, namely Arrival Cities by Doug Saunders and Implosions/Explosions edited by Neil Brenner, that are representative of two major discourses on the urban, respectively, the “Urban Age” and planetary urbanization, currently favored by policy bodies and (some) academics. Their limited engagement with politics leads me to conclude with a call for a feminist mode of situated knowledge production to engage with (the limits of) urban theory and the urban as a site of praxis.     

北京城市边缘区城市化过程与空间扩展——以大兴区为例

城市边缘区空间扩展研究是探讨城市未来空间结构和形态演变的基础。本文基于北京大兴区1994、2001和2006年3期TM遥感影像资料提取城镇用地信息,通过对城市扩展强度、城市扩展梯度、城市边缘区空间扩展模式等建设用地的总体扩张行为进行研究,分析研究区十多年来城市化进程中城镇建设用地扩展的时间过程和空间格局特征,对明确未来城市边缘区土地利用发展方向,提高土地利用效率和城乡建设效益提供基本依据。结果显示,大兴区城市土地利用扩展强度不断增强;中心城区以及中心区面积的不断扩张,导致建设用地在高指数区间集中的趋势明显,农村地区小城镇建设的高速发展使得低指数区间的建设用地面积大幅度增加;根据城市化扩展梯度,大兴区分为城市化高速扩展带、城市化快速扩展带和城市化低速扩展带;紧邻中心区的城市化高速扩展带,以集中连片式扩展为主,该模式在边缘区空间扩展中居于主导地位。城市化快速发展带土地利用以轴向扩展模式为主,轴向扩展稳定地影响着大兴区城市化进程。独立发展模式随着城市经济的快速发展其影响将明显增强,逐渐成为城市边缘区空间扩展的主要形式。     

城市异速标度研究的起源、困境和复兴

系统总结了城市异速标度研究的学术源流、量纲困境和现状特征,重点探讨了城市化异速标度分析的前景和意义。异速标度是城市研究的基本理论方法之一,该方法起源于20世纪50年代的生物学和一般系统论。由于量纲难题,城市异速分析经过一段时间的研究热潮之后趋于冷落;由于分维概念的引入,异速标度关系摆脱了量纲困境;由于相关领域的推动,城市异速分析方法复兴。异速生长和异速标度分析在城市形态、城市生态、城市性态、城市动态以及城市体系等诸多领域都有应用。如今,异速生长正在与分形和自组织网络理论相互融合,发展成为基于一般标度律的城市过程和格局的集成分析方法。由于城市化与城市形态、城市体系等方面的密切相关,异速标度分析极有前景的一个发展方向可能是城市化研究。城市化异速分析可望将不同类型的城市异速标度研究成果组织成一个完整的逻辑框架。     

Building a sustainable urban future: An Auckland experience

Abstract:  The Untouched World Sustainable Cities Youth pilot project was held in Auckland in July 2005. This article outlines the activities that school students were involved in during the week and reflects on the nature of the learning experience. Whilst not specifically targeted at geography students or teachers, the project does support the outcomes of senior high school geography programmes.     

Public places and empty spaces: dislocation,urban renewal and the death of a French plaza

This article examines the dislocations produced when competing understandings of public space come into contact. Focusing on Montpellier, France, where an urban renewal program has seen portions of the city-centre renovated, the article considers the breaking apart of a North African commercial cluster under the guide of French heritage protection. Arguing that such action is tiedto municipal urban politics and wider trajectories that place diverse identities in a separate category, I trace the process through which a plaza encompassed in the urban renewal program has been labelled as “empty” and “dead” space. Suggesting that the relocation of a well-used outdoor food market is an instance of public space being deliberately emptied of its social and civic function, I argue that such sites are better defined as “municipal spaces”, entities that are firmly in the realm of the state, rather than ones within the purview of diverse publics.     

基于城市群整合发展的中原地区城市体系结构优化

在中原城市群的整合发展中,建设结构完善、功能强大的城市体系是一项特殊重要的历史任务,而城市体系的"结构优化"更是首当其冲的必须妥善解决的关键问题。城市体系结构优化的实质是:通过政府的宏观规划调控和城市群内各地域单元的整合,实现不同等级、不同规模、不同职能的城市在空间平台上的高度和谐,从而实现城市体系整体实力的提升,最终实现城市群的可持续发展。基于城市群整合发展的中原地区城市体系结构优化的主要内容是:第一,用"城市中心性强度"法来划分中原城市群地区所有城市的等级,进而构建出4个等级城市体系的层次。第二,采用灰色系统GM(1 ,1)模型并根据人口的机械增长基础,求出各城市2020年非农业人口的优化指标。第三,运用纳尔逊(H.J.Nelson)统计分析原理和方法,确定各城市的优势职能、突出职能以及重点发展行业。第四,构建了"两圈、双核、四带、一个三角"的城市体系空间布局和功能发挥的整体框架。     

城市扩张进程中水环境污染成本响应模拟

本文旨在建立地表水环境污染对城市扩张的响应模型,以模拟预测城市扩张进程中的社会经济发展、土地效益和生态环境成本的动态变化过程。首先,应用遥感影像解译技术,对城市扩张引起的土地利用变化进行定量分析;其次,基于社会福利最大化和绿色GDP(GGDP)等理论,模拟城市地表水环境污染成本在不同社会经济情景下对城市扩张的响应。以西安为典型研究区域,分析了该区在1996~2006年间城市扩张行为及其对地表水环境污染的影响,结果表明:在不同的社会经济发展条件下,有着不同的城市扩张最优点(均衡点);城市扩张引起的边际生态环境成本小于平均土地效益时,城市扩张会使社会福利变好,城市扩张应继续;技术进步可优化地表水环境污染成本和提高土地利用效率,优化城市扩张均衡点;在现有的经济技术水平发展条件下,理论上西安城市扩张最优点在2024年达到。     

快速城镇化背景下长三角城镇建设用地群态化特征及演变模式

城市群作为国家新型城镇化的主体形态,表征其空间结构和组织演变的城镇建设用地具有明显"群态化"特征.借鉴群落生态学理论,利用城镇用地开发速率指数、景观指数、核密度估计等方法 ,对长三角城市群1978-2017年城镇建设用地的规模分布、形态变化和集聚状态进行探讨,提炼出快速城镇化背景下城镇建设用地的群态化演变模式.研究结果...     

西安市城市化与都市农业发展耦合关系研究

城市化以其强烈的市场效应与辐射功能带动了都市农业的发展,但同时又对都市农业的水土资源、生态环境造成负面影响;都市农业又通过其生产、社会及生态功能推动城市化发展。揭示两者之间的作用规律,对解决城市经济、社会和生态问题,快速推动都市农业发展,协调城乡关系具有重要意义。本文在构建城市化水平与都市农业发展水平测度指标体系的基础上,通过主成分分析法和相关分析法,探讨了城市化与都市农业发展之间的相互作用机制,并定量分析了两者之间的耦合关系。结果表明：① 近10 年,西安市城市化水平与都市农业发展水平都呈上升的趋势,且二者表现出显著的同步性;② 西安城市化水平和都市农业发展水平呈显著的正相关,相关系数达0.955;③ 西安城市现代化水平因子、城市生活质量水平因子和人口与经济结构因子是推动城市化的3 个主要因子,其中城市现代化水平因子是推动西安都市农业发展的主导因子。     

A study on urban system planning of Xiantao city in Hubei Province,China

Xjantaocity,lyingbetween112'56'E~113'49'E,30'04'N~30'32'N,issighttedinJianghanPlainofcentral-southHubeiProvince.ItneighboursWuhancitytotheeastQianjiangstytothewest,facesHonghucityandJianlicountytotilesouthacrosstheDongiinhiverandissepalatedbyHanjianghiverfromThalnencityandHallchuancountytothenorth.Itcoversanareaof2535km2.In1992itStotalpopulahonwasestjjnatedat143.2x10',ofwhichnon-agricultulalpopulahontotalled35.49x10',accounhngfor24.79%ofthecity'stotalpopulahon.ItsGNPwas24.3x108yUan,of…     

21世纪中国城市未来的软规划与生态文明建设

文章旨在通过理念性的探讨,试就“中国在日益深入地参与全球贸易和投资中所面临的主要挑战”这一议题激发大家的讨论。文章论述了当代城市化理论现状、城市化和可持续发展之间的关系对中国国家发展目标的影响以及中国21世纪面临的发展挑战,认为：1）中国应注重基于本土发展经验的理论知识构建,以指导自身的城市化道路。特别地,中国需要平衡经济增长与可持续发展之间的关系,充分利用和部署生态资本,推动生态文明建设;2）以部署生态资本为重心的“软规划”在未来规划中将占据更重要的地位,为此需要进行体制改革、机构重组以及加强政府部门与私营部门和民间社会之间的合作;3）扩展型都市区可在生态文明建设中发挥更大作用,努力打造一个可持续的、宜居的和有经济活力的体制性框架,从而为“一带一路”倡议提出的国际贸易和投资深化发展提供基础。     

Impact of urban expansion on regional tempera-ture change in the Yangtze River Delta

Based on non-radiance-calibrated DMSP/OLS nighttime light imagery from 1992 to 2003, urban land area statistical data, meteorological data and land surface temperature data retrieved by MODIS and NOAA/AVHRR data, the influence of urbanization on regional cli-matic trend of temperature in the Yangtze River Delta (YRD) was analyzed. Conclusions are as follows: 1) There is a significant urbanization process from 1992 to 2003 in the YRD. Four city clusters of Nanjing–Zhenjiang–Yangzhou, Suzhou–Wuxi–Changzhou, Shanghai and Hangzhou Bay form a zigzag city belt. The increase rate of annual mean air temperature in city-belt is 0.28–0.44℃/10a from 1991 to 2005, which is far larger than that of non-city-belt. 2) The urban heat island (UHI) effect on regional mean air temperature in different seasons is summer>autumn>spring>winter. 3) The UHI intensity and the urban total population logarithm are creditably correlated. 4) The UHI effect made the regional annual mean air temperature increased 0.072℃ from 1961 to 2005, of which 0.047℃ from 1991 to 2005, and the annual maximum air temperature increased 0.162℃, of which 0.083℃ from 1991 to 2005. All these indicating that the urban expansion in the YRD from 1991 to 2005 may be regarded as a serious climate signal.