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1.
《Geoforum》2015
This study explores the spatial transformation of urban South Africa since the ending of Apartheid rule two decades ago. It places this experience within the context of countries which have also gone through a “loosening” of political control and of related controls over spatial arrangements. The paper provides a discussion of South Africa’s spatial trends between 1996 and 2011, focusing on urbanisation; urban form; and socio-spatial segregation, and exploring the extent to which changes identified are shaped by the state, private sector investment, and the everyday actions of households and individuals. It shows that South Africa’s urban spatial transformation, post-Apartheid, is both idiosyncratic and comparable. The consequences of spatial controls, and of their loosening, have been diverse across countries, but also within countries. Loosening has led to differing relationships between state, citizenry and private enterprise, and to complex new crossing points between these groupings, affecting spatial change. In South Africa, significant trends have been: movement to the major cities where employment growth is stronger; levels of racial desegregation; and densification of parts of cities and towns, along with peripheral growth and employment decentralisation. Many of the changes however are differentiated across space and between settlements. While proactive state policies have had some impact (not necessarily in the direction of desired spatial transformation), and there are complex interrelationships, our empirical studies suggest that the major weight of evidence is towards the roles of private enterprise and people in shaping spatial change, enabled in part by forms of state loosening. 相似文献
2.
Herslund Lise Byskov Jalayer Fatemeh Jean-Baptiste Nathalie J&#;rgensen Gertrud Kabisch Sigrun Kombe Wilbard Lindley Sarah Nyed Patrik Karlsson Pauleit Stephan Printz Andreas Vedeld Trond 《Natural Hazards》2015,82(2):149-172
In this paper, we develop and apply a multi-dimensional vulnerability assessment framework for understanding the impacts of climate change-induced hazards in Sub-Saharan African cities. The research was carried out within the European/African FP7 project CLimate change and Urban Vulnerability in Africa, which investigated climate change-induced risks, assessed vulnerability and proposed policy initiatives in five African cities. Dar es Salaam (Tanzania) was used as a main case with a particular focus on urban flooding. The multi-dimensional assessment covered the physical, institutional, attitudinal and asset factors influencing urban vulnerability. Multiple methods were applied to cover the full range of vulnerabilities and to identify potential response strategies, including: model-based forecasts, spatial analyses, document studies, interviews and stakeholder workshops. We demonstrate the potential of the approach to assessing several dimensions of vulnerability and illustrate the complexity of urban vulnerability at different scales: households (e.g., lacking assets); communities (e.g., situated in low-lying areas, lacking urban services and green areas); and entire cities (e.g., facing encroachment on green and flood-prone land). Scenario modeling suggests that vulnerability will continue to increase strongly due to the expected loss of agricultural land at the urban fringes and loss of green space within the city. However, weak institutional commitment and capacity limit the potential for strategic coordination and action. To better adapt to urban flooding and thereby reduce vulnerability and build resilience, we suggest working across dimensions and scales, integrating climate change issues in city-level plans and strategies and enabling local actions to initiate a ‘learning-by-doing’ process of adaptation.
相似文献3.
Lise Byskov Herslund Fatemeh Jalayer Nathalie Jean-Baptiste Gertrud Jørgensen Sigrun Kabisch Wilbard Kombe Sarah Lindley Patrik Karlsson Nyed Stephan Pauleit Andreas Printz Trond Vedeld 《Natural Hazards》2016,82(2):149-172
In this paper, we develop and apply a multi-dimensional vulnerability assessment framework for understanding the impacts of climate change-induced hazards in Sub-Saharan African cities. The research was carried out within the European/African FP7 project CLimate change and Urban Vulnerability in Africa, which investigated climate change-induced risks, assessed vulnerability and proposed policy initiatives in five African cities. Dar es Salaam (Tanzania) was used as a main case with a particular focus on urban flooding. The multi-dimensional assessment covered the physical, institutional, attitudinal and asset factors influencing urban vulnerability. Multiple methods were applied to cover the full range of vulnerabilities and to identify potential response strategies, including: model-based forecasts, spatial analyses, document studies, interviews and stakeholder workshops. We demonstrate the potential of the approach to assessing several dimensions of vulnerability and illustrate the complexity of urban vulnerability at different scales: households (e.g., lacking assets); communities (e.g., situated in low-lying areas, lacking urban services and green areas); and entire cities (e.g., facing encroachment on green and flood-prone land). Scenario modeling suggests that vulnerability will continue to increase strongly due to the expected loss of agricultural land at the urban fringes and loss of green space within the city. However, weak institutional commitment and capacity limit the potential for strategic coordination and action. To better adapt to urban flooding and thereby reduce vulnerability and build resilience, we suggest working across dimensions and scales, integrating climate change issues in city-level plans and strategies and enabling local actions to initiate a ‘learning-by-doing’ process of adaptation. 相似文献
4.
以新疆16座城市为研究对象, 运用多时相卫星遥感资料, 利用遥感和GIS技术提取城市的空间特征信息, 并通过城市扩展强度、扩展速率以及城市空间形态紧凑度和分形维数等指标定量分析了1990-2010年以来新疆城市扩展时空动态变化的过程和特征. 结果表明: 新疆城市的空间分布由其独特的自然环境和绿洲经济所决定, 许多城市的发展依托于绿洲, 城镇的形成具有"亲水性"的特点, 由于新疆地域辽阔, 交通干线附近往往形成城镇相对集中的城市带或城市群. 南北疆城市之间在扩展速度及强度上存在较明显的差异, 位于北疆天山北坡经济带上的城市大多属于扩展速度相对较快、扩展强度相对较大的扩张类型, 而南疆城市的扩展速度则相对较慢、扩展强度也相对较小.通过对城市紧凑度和分维数变化的分析发现, 新疆城市平均紧凑度呈下降趋势, 而分形维数呈增长的趋势, 说明整体上新疆城市空间结构有趋于松散化的趋势, 城市的空间结构不够合理, 有待改善. 相似文献
5.
O. Gritsai 《GeoJournal》1997,42(4):341-347
This paper deals with the trends of economic restructuring in Moscow in the 1990s under globalization and reforms. The comparison of structural shifts in Moscow with the largest cities of the West gives an idea about the position of the Russian capital on the trajectory of post-industrial transformation. The analysis covers three dimensions: a) general trends of post-industrial restructuring, b) the role of large cities in national economies, and c) universal and special trends of intra-urban transformation. The reforms of the 1990s initiated many new developments in the economic life of Moscow, making it more similar to the Western cities, both in general sectoral structure and intra-urban landscape. Nevertheless, Moscow still lags far behind the world cities as regards the stage of the most important post-industrial processes. The conflict between new market developments and the inherited patterns of the socialist city becomes one of the driving forces of the economic transformation in Moscow as a whole and in different types of its districts. 相似文献
6.
Luca Salvati 《GeoJournal》2016,81(2):319-332
In the recent decades southern European cities experienced morphological changes and a demographic transition towards zero (or negative) growth and aging. Population dynamics shifted from the impressive growth of the post-industrial period into recent de-concentration processes determining the spillover of commercial and residential settlements across the surrounding rural areas. Based on long-term demographic data, the present study hypothesizes that urban expansion did not follow a one-way linear path from compactness to dispersion while reflecting differentiated growth patterns based on the specific socioeconomic context at the local scale. Along a sufficiently long time period non-linear expansion waves alternating settlement densification and scattering are expected to be found especially in complex urban contexts such as those developed in the Mediterranean region. This hypothesis was tested for a paradigmatic case study in southern Europe (Athens, Greece) using demographic data covering 160 years (1848–2011). Urban growth in Athens was assessed through the analysis of long-term census data made available on a district level. These data provide information on the spatial distribution of resident population and characterize distinct expansion waves according to the dominant socioeconomic context. Results of the study were discussed in the light of the debate on future development of the Mediterranean cities and the (changing) economic relations with the surrounding region. 相似文献
7.
合理选择宝鸡城市空间拓展方向,推动城市空间集约化发展,达到城市与区域生态协调发展.在大量查阅相关资料的基础上,运用定性描述和带形城市空间扩展理论进行探讨.宝鸡城市空间扩展分四个阶段,自然地理环境、经济发展水平及交通条件是驱动城市空间扩展演化的主要动力.城市空间拓展必须合理选择发展方向,通过交通及生态建设,实现市域城镇间... 相似文献
8.
9.
基于多源多时相数据集的喀什市近70a城区空间扩展遥感研究 总被引：2，自引：1，他引：1
使用民国34年（1945年）1∶1×104地形图、1968年CORONA影像及近期Landsat5和2015年GE影像数据,使用遥感技术以多元多时相遥感数据融合和GIS挖掘技术为支撑,采用等扇分析法和重心转移矩阵分析了喀什市70a城市空间形态整体扩展特征,各方向上的扩展速度、强度以及空间重心转移的方向、强度。结果表明：1945-2015年间喀什市空间形态经历了带状扩展向团状扩展的转变,城市整体空间扩展强度不断加剧,空间扩展速度呈先上升后下降再上升的趋势,空间重心向东南方向绿洲腹地转移1009m,侵占甚多绿洲耕地,城市空间扩展模式粗放,亟待调整。 相似文献
10.
We have systematized the effects associated with climate change on urban spaces in Chile reported between 2000 and 2012. The method was based on a review of scientific articles in three databases (Scopus, Web of Knowledge and Scielo) using 32 keywords. Only 14 research papers were found related to climate change in urban spaces, most of which were case studies focused on the capital, Santiago. The main effects on urban spaces were found in four areas: (1) increase in temperature (heat islands, heat waves), (2) health problems in vulnerable populations (cardiac complications, heat stroke, and respiratory diseases), (3) increased demand for water, and (4) damage to the urban infrastructure with resulting risk to the population. In these circumstances the following measures are needed: (1) effective incorporation of the potential impacts of climate change into territorial planning instruments, (2) increased green areas to mitigate the impact of heat waves, (3) limiting of housing or public services in areas at risk, (4) encouraging the design of adaptation plans by involving the vulnerable population, and (5) implementing water conservation measures. We conclude that climate change is causing effects in urban areas that should be considered in the design and expansion of cities. 相似文献
11.
Kee-Bom Nahm 《GeoJournal》1999,49(3):289-299
In recent years, central Seoul has been experiencing a dynamic transformation. In the process of reorganization of the urban
industrial structure including tertiarization and quaternarization of the economic base of Seoul, business services are growing
very rapidly and large scale urban renewal projects are quickly implemented. Downtown office activities become a nucleus for
economic performance of Seoul and high-rise office buildings steer the landscape transformation of central Seoul. Even though
there appears to exist some evidence that office districts have dispersed to several subcenters, major office activities are
still concentrated in central Seoul. This paper redefines office industry in a narrow sense comprising only relevant economic
sectors and office buildings as office activity-functioning units. It then explores the industrial networking and territorial
specialization of office activities focusing on the dual process of concentration and dispersion in Seoul. The changing characteristics
of the downtown linkages of office activities in this post-industrial era transforms the spatial economy of central Seoul
into a more flexible and volatile system, while territorial concentration of power and control functions are fortified at
the same time. Finally, the paper addresses the development of manufacturing- tertiary-quaternary industrial complexes, which
can be regarded as emerging industrial clusters, producing the cultural economy of urban space and images for clients and
customers, in relation to urban competitiveness and territorial specialization of large metropolitan areas.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
12.
Natural Hazards - The occurrence of major natural disasters in recent years has impacted large cities worldwide and boosted the need of assessing urban resilience. As a key factor of resilience,... 相似文献
13.
石羊河流域是流域经济社会可持续发展研究的重点区域之一。为找出流域城镇化用地空间扩展的机理,从社会经济、区位交通、生态约束出发,开展了城镇空间扩展用地评价与预测研究。首先,利用改进的土地适宜性评价方法,找出城镇扩展可能性和各乡镇适宜性高值区的空间格局,发现其主要位于流域中部绿洲生态功能区,沿G30高速公路和312国道分布,以县城/城区为中心呈星形扩散。然后,利用经过精度检验的土地转化模型（LTM）,在适宜性评价因子的基础上模拟城镇扩张。结果表明：凉州区和金川区为流域发展的"两核",312国道天祝至永昌段、211省道凉州至民勤段、212省道永昌至金川段为流域发展的"三带"。上述结果可为政府制定流域发展规划提供参考。 相似文献
14.
为揭示大连城市用地扩张的空间分布特征,基于DSMP/OLS夜间灯光数据提取1998—2013年大连地域边界,并得到各地区的灯光阈值及地域边界分区统计面积。通过计算不同时期不同区域的城市用地增长景观格局指数,研究该市16年来的城市用地扩张方向、强度和空间景观格局变化,以揭示大连20年来城市用地扩张的空间分布特征。结果表明,城市用地扩张主要集中在沙河口区、中山区和西岗区,并以其为中心向甘井子区、旅顺口区、金州区等区域扩张。城市用地空间格局总体基本稳定,受地理条件、空间距离、经济发展和政策指引等因素的影响,城市用地扩张在不同方向上差异化显著。研究成果可作为大连城市规划的依据。 相似文献
15.
In the course of the last 50 years, the landscape in Israel has undergone major changes, due to accelerated urbanization following population growth. These processes had increased the pressure on the open land, especially in areas of urban expansion. Recognizing that Governments and local Municipalities had failed to stop the consequent loss of public open spaces, not only in Israel but worldwide, had lead recently many communities to adopt new solutions in the form of private open spaces. In this article we present a “step ahead of time”: a case of privately owned land, set aside as public green area during the 1920s in a neighborhood called “Ahuza Herbert Samuel” (Herbert Samuel, the first High Commissioner of Palestine under the British Mandate), located in the City of Haifa, in Northern Israel. The roots of this unique phenomenon during the 1920s could be linked to several sources of influence: Colonial town planning concepts, the emergence of garden cities and garden suburbs and most importantly to concepts brought in by the leaders of the immigrant community coming from Rumania. Photogrammetric and GIS analysis of this phenomenon had revealed that it had prevailed throughout 75 years of constant and massive increase in the demand for built-up areas in Israel in general and in Ahuza neighborhood in particular. The success in preserving these open areas gains current relevance in view of recent trends in the Western world of allocating privately owned green areas for public use. 相似文献
16.
Olalekan John Taiwo 《GeoJournal》2013,78(1):103-115
The issue of food security has received increasing emphasis in developing countries, particularly in the cities. The emphasis on food security has engendered agricultural expansion and encroachment on the coastal and inland wetlands in these nations. To facilitate and sustain the security of food in the developing countries local and international policies have been designed and employed; they have specifically targeted abounding food production towards ensuring human survival in the cities. However, the various ecological and socio-economic benefits derivable from the preservation of wetlands and inland valleys in these urban environments may be lost, with the transformation in the land use and cover. This study is therefore concerned with how wetland degradation and loss can be checked and mitigated, focusing on the developing countries and their cities. In this respect, the farmer’s awareness of the impacts of wetland cultivation and the role of accessibility, socio-economic and biophysical factors influencing the choice of wetland farming are examined. To this end, structured questionnaire on choice of wetland agriculture in the urban and periurban wetland areas of Lagos city was administered to the farmers. Simple frequency analysis is used to explain and interpret the data generated. The data reveals a generally low level of farmers’ awareness of the implication of wetland cultivation; it shows different categories of factors influencing the choice of wetland farming. Provision of irrigation infrastructure and improvement in living standard of the people through poverty eradication can discourage disadvantageous encroachment on wetlands in cities. 相似文献
17.
在全面收集地质和工程勘察资料基础上,系统梳理了成都市地下空间资源综合利用需要防范关注的7类地质问题以及需要统筹保护的4类地质资源。根据城市地下空间资源综合利用约束性地质要素（地质问题、地质资源）和地质结构在垂向上的差异,将成都市0~200 m地下空间划分为0~30 m、30~60 m、60~100 m、100~200 m 4个层位,在此基础上,提出了成都市地下空间分区、分层开发利用建议,编制了《支撑服务成都市地下空间资源综合利用地质环境图集》。图集范围覆盖成都市中心城区、高新西区、高新南区、国际生物城、天府新区成都直管区、天府空港新城、简州新城、淮州新城等重点地区,包括39张图件和1个地质调查报告。图集为成都市城市地下空间综合利用、城市空间优化拓展、城市功能品质提升以及国土空间开发、空间转型升级和城市集约、绿色、可持续发展提供了地质依据,对于全国其他城市开展同类图集编制具有示范和借鉴意义。 相似文献
18.
贵州省城镇用地扩展强度时空分异及影响因素 总被引：1，自引：1，他引：0
以贵州省1995年、2000年、2007年TM遥感影像资料为数据源,利用Er-das软件对该三期影像进行矫正和监督分类,应用ArcView进行修改。然后,再以ArcGIS空间分析模块,提取贵州省1995年、2000年、2007年三个时期的城镇土地利用数据。在此基础上,运用城镇扩展强度指数公式计算城镇扩展强度指数,并从交通、经济和自然环境等方面对贵州省城镇土地利用扩展的影响因素进行分析研究。结果表明:(1)2001-2007年,高速扩展城镇16个,高于1995—2000年期间的5个;(2)从空间上看,南北(遵崇公路、贵遵公路、贵新公路及国道210)沿线、东西(凯麻公路、贵黄公路以及国道320)沿线大城市扩展较快,并以交通十字交点为中心形成中高速扩展区域,而且这种由节点城镇向轴线发展的趋势表现日益突出。(3)从扩展强度等级上看,存在扩展强度等级逐渐递增的规律,即由低速扩展→低中速扩展→中速扩展→中高速扩展→高速扩展。道路等级与城镇扩展强度成正比例关系,即道路等级越高,其沿线城镇土地利用扩展强度越大;经济是城镇扩展的重要影响因素,经济的快速增长能提高城镇扩展强度;平坦开阔的地形地貌将利于城镇扩展,而山高坡陡等崎岖的地形地貌将阻碍城镇的扩展。 相似文献
19.
基于夜间灯光的1992-2012年甘肃省城市空间扩展研究 总被引：2，自引：1，他引：1
利用1992年、2002年和2012年DMSP/OLS 夜间灯光遥感影像、MODIS NDVI产品、LandsatTM/ETM影像和统计数据,提取甘肃省县级及以上城市的建成区轮廓,对比分析了统计-植被指数法与现有基于DMSP数据中普遍采用的4种常规方法在快速提取城市轮廓中的优劣。结果表明：统计–植被指数法较好地集成了统计数据法的高效、计算简便、数据量小的特点,以及较高分辨率空间数据法对细节反映好的优势,提取的结果误差较其余4种方法低。对提取的城市建成区以DMSP灰度值为权重计算了城市重心轨迹,并采用城市扩展强度和城市紧凑度指数,分析了近20a甘肃省主要城市空间形态的变化特征,城市建成区的扩展模式主要表现为“圈层式”延伸和“跳跃式”新城区的建立。 相似文献
20.
A flood vulnerability index for coastal cities and its use in assessing climate change impacts 总被引：4，自引：2，他引：2
Worldwide, there is a need to enhance our understanding of vulnerability and to develop methodologies and tools to assess vulnerability. One of the most important goals of assessing coastal flood vulnerability, in particular, is to create a readily understandable link between the theoretical concepts of flood vulnerability and the day-to-day decision-making process and to encapsulate this link in an easily accessible tool. This article focuses on developing a Coastal City Flood Vulnerability Index (CCFVI) based on exposure, susceptibility and resilience to coastal flooding. It is applied to nine cities around the world, each with different kinds of exposure. With the aid of this index, it is demonstrated which cities are most vulnerable to coastal flooding with regard to the system??s components, that is, hydro-geological, socio-economic and politico-administrative. The index gives a number from 0 to 1, indicating comparatively low or high coastal flood vulnerability, which shows which cities are most in need of further, more detailed investigation for decision-makers. Once its use to compare the vulnerability of a range of cities under current conditions has been demonstrated, it is used to study the impact of climate change on the vulnerability of these cities over a longer timescale. The results show that CCFVI provides a means of obtaining a broad overview of flood vulnerability and the effect of possible adaptation options. This, in turn, will allow for the direction of resources to more in-depth investigation of the most promising strategies. 相似文献