首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 93 毫秒
1.
Did Black Metropolises, that is, large black communities in major cities, hold unique opportunities that helped blacks to advance occupationally in the early twentieth century? The present study addresses this question, using Census data to test hypotheses, based on urban geographic principles, about the distribution of Black Metropolises’ locational advantages. The results show that blacks’ representation in key middle-to-upper-status occupations declines precipitously across Black Metropolises, often following an exponentially descending Pareto curve, suggesting that blacks’ opportunities to enter such occupations are concentrated into a small number of large urban black communities. The results further indicate that the locational-advantage benefits of the largest, most segregated, and most centrally positioned Black Metropolises are limited to a few high-status professions and a narrow range of occupations involving cultural expression, entertainment, and public service. These findings challenge claims that blacks’ socioeconomic standing was substantially uplifted in the early twentieth century by unique opportunities in large black communities of major cities.  相似文献   

2.
Facing natural disasters is a priority challenge for cities, exacerbated by increases in urban population and climate change. Improving the resilience of cities is a critical need for the international community and especially for territories exposed to multiple risks, such as Chile. Although disasters are always tragic, the recovery and reconstruction post-disaster may provide a unique opportunity to prevent future suffering, enhancing the resilience of local communities. This paper presents the analysis of two Chilean reconstruction programmes applied in Mehuin and Dichato, after the earthquake and tsunami of 22 May 1960 and 27 February 2010, respectively. In both cases, reconstruction programmes were supported by the Chilean Government, but using different approaches: one focused on providing housing for people injured in the earthquake, while the other also included urban amenities and services. This article proposes an urban morphology analysis framework; in addition, it presents the assessment of the two case studies before and after a disaster, thus evaluating their resilience. By comparing urban morphology resilience pre- and post-disaster, a discussion about the effectiveness of two reconstruction approaches is presented. Finally, conclusions and recommendations to better integrate resilience into urban planning are proposed, with the aim of opening the discussion about how to make cities more resilient to natural disasters.  相似文献   

3.
Feng Deng 《GeoJournal》2017,82(2):231-246
Research on gated community in Chinese cities has been growing very fast, but empirical studies are limited, especially those on the relationship between gated community and residential segregation. A retrospective questionnaire survey was conducted in three gated communities in Chongqing, China. The findings from the survey include that, after moving into the gated communities, many homeowners’ contact with other people decreases. It is also found that homeowners’ participation in local public affairs decreases. These results hold even when we compare with the reference group and control for duration of stay. They support the view that gated community aggravates residential segregation. However, the survey shows that many homeowners feel the income differences among the neighbors increase and the changes of several types of external activities don’t show a consistent pattern. All these empirical findings suggest that a complex relationship between gated community and residential segregation exists in urban China and the removal of work unit from the housing system affects people’s experience in gated community.  相似文献   

4.
In South Africa attempts are being made to address the socio-spatial distortions of the apartheid era through a more equitable distribution of resources, and the re-drawing of municipal geographical boundaries. However, boundaries are not neutral geographic lines. Boundary changes are often associated with a redistribution of political power and resources. The aim of this paper is to analyse the effects of the contemporary territorial and administrative restructuring on urban dynamics in South Africa. More specifically, the focus is on how the process of territorial restructuring impacted on metropolitan areas as well as on secondary cities and their hinterlands. Examining and elucidating the manner in which various social, economic and political forces have manifested themselves in the process of boundary delimitation in a major metropolitan centre as well as adjacent rural areas is a central theme of this paper. There were considerable contestations over the delimitation of new local government boundaries. Affluent metro authorities like that in Durban were opposed to the spatial extension of their boundaries because of the costs of the providing services and infrastructure in the deprived margins. Similarly, there was concern that incorporation of rural areas will result in increased municipal service charges being imposed on these communities. Tensions were heightened between urban and rural regions because traditional leaders believed that their territorial jurisdiction and authority were being undermined. In other parts of the country, the merger of traditionally white and black fragments of secondary cities often resulted in many black locations continuing to be marginalized. There appears to be neither the political will nor the economic capacity to upgrade these zones of marginalized urban communities. While the Municipal Demarcation Board was largely successful in eliminating the political geography of apartheid at a macro- scale, this paper suggests that the greater challenge for government and policy makers is to reduce the socio-spatial and economic inequalities which appears to be still very high and perhaps increasing. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

5.
In recent years, there has been heightened interest in creating more environmentally sustainable forms of urban development in China. Central in these greening initiatives has been increased attention on promoting public participation in community-based environmental activities. Focusing on China’s green community initiatives, we examine the production and effects of participation in a state-led development program. Our analysis considers how incentives for program organizers and participants are structured by broader political and economic imperatives facing Chinese cities. We also consider what influence China’s history of neighborhood-based mobilization campaigns had on the meanings and methods of participation in green communities. To understand how urban development processes and memories of mobilization influence participation at the local level, we present two examples of the community greening process from the city of Guangzhou, comparing policy outcomes between a new and older neighborhood. This article seeks to demonstrate that the participatory processes associated with such an urban environmental initiative cannot be adequately understood without reference to earlier participatory practices and broader policy priorities guiding development in Chinese cities.  相似文献   

6.
Ke Chen  Shuming Bao  Yong Mai  Wen Lv 《GeoJournal》2014,79(2):255-266
In the midst of global economic and financial integration, there are increasing cross-border capital flows between China and the rest of the world. Foreign financial businesses also start to play more important roles in the nation’s market after waves of financial reforms. Within such a background, this study aims to investigate the agglomeration and location choice of overseas financial institutions in Chinese cities. Data from the 2004 China Economic Census show that foreign financial establishments, including banks, insurance companies, and other financial service businesses, were mainly agglomerated in coastal cities. In particular, three major urban areas, Shanghai, Beijing, and Guangzhou, concentrated a majority of overseas financial institutions. Results from regression models show that foreign businesses’ location choice is greatly influenced by a city’s urban economy, involvement in the global market, and telecommunication infrastructure. However, we do not find a significant link between foreign financial institutions’ market entry and the size of domestic financial centers in China.  相似文献   

7.
Lu  Yi  Li  Rui 《Natural Hazards》2020,104(1):853-882
Natural Hazards - There have been many practical programs suggested for building resilient cities and communities, many of which have been driven by governments to focus on disaster prevention...  相似文献   

8.
9.
Mobilities in settler states have become a defining feature of indigenous spatiality. This is mainly due to the structural disadvantage of indigenous communities in relation to urban locations. In Israel, Palestinian citizens are relocating to Jewish cities because of systemic discrimination, primarily in the allocation of land and housing construction permits in Arab locales. Yet, as this paper shows, their movement is neither unidirectional nor an one-time event, but ongoing and circular. Able to enjoy only certain economic and social rights in indigenous spaces and other rights in settler spaces, Palestinian citizens continuously commute between the two. Utilizing a human rights based approach, the paper unpacks Palestinian mobility practices to illuminate a lacuna in the literature, which has overlooked the quest for rights as a driving force of indigenous mobilities. The paper further demonstrates that circular mobilities become a generative act that connects the settler city to neighboring localities in a way that undermines the separation between ‘Jewish’ and ‘Palestinian’ spaces, and collapses the distinction between the ‘urban’ and ‘regional.’ Rather than attempting to integrate within the city, Palestinians incorporate the city within their own ethno-regional topography, thereby asserting their presence and a claim to the city-space itself.  相似文献   

10.
Black smoker chimneys and biological vent communities have been identified at many sites on the deep seafloor, particularly along oceanic spreading centers. We report the largest and oldest known, microbe-rich sub-meter-sized black smoker chimneys and mounds from a 1.43 billion-year old sulfide deposit in a continental graben in northern China. These chimneys are especially well preserved, with characteristic morphology, internal textures and internal cylindrical mineralogical zonation. Four main types of chimneys are distinguished on textural and mineralogical criteria, exhibiting either Zn–Fe-sulfide or Pb–Zn–Fe-sulfide internal cylindrical mineralogical zones. The chimneys mark vent sites in submarine grabens indicating focused flow-venting processes. The fossil chimneys have mineralogical and geological evolutionary features similar to their counterparts on the modern seafloor and other submarine hydrothermal vents. Black smoker vent fluids and seafloor tectonism played important roles for formation of the massive sulfide deposits in the Mesoproterozoic.We also report the first known, remarkably diverse assemblage of fossil microbialites from around and inside Precambrian vent chimneys, demonstrating that Proterozoic life flourished around submarine hot vents and deep within the chimney vent passages. Filamentous, spherical, rod, and coccus-shaped fossil microbes are preserved preferentially on sulfide precipitates. Based on the depth and setting of the fossil biota, the organisms that produced the microbialites were likely sulfate-reducing chemosynthetic and thermophyllic microbes. Textural and mineralogical evidence shows that biomineralization processes enhanced chimney growth and sulfide precipitation.Close association of microorganisms with sulfide chimneys in modern deep-sea hydrothermal vents and younger ophiolites has sparked speculation about whether life may have originated at similar vents. However, little is known about fossil equivalents of vent microfossils and black smoker chimneys from Earth's early evolution. The fossilized microorganisms from the Gaobanhe black smoker chimney sulfide deposits include thread-like filaments with branching and twisted forms and preserved organic carbon, representing fossilized remnants of microbial mats metabolized at high temperatures characteristic of venting fluids. The preservation of fossil microorganisms provides evidence that microbial populations were closely associated with black smoker chimneys in Earth's early history. The microbial population clearly constitutes the site for mediating mineral formation. These ancient microbial fossils lead to a much better understanding of early life on the deep seafloor. The discovery of the Mesoproterozoic microfossils within black-smoker hydrothermal chimneys indicates that hydrothermal activity around sea-floor vents supported dense microbial communities, and supports speculation that vent sites may have hosted the origin of life.  相似文献   

11.
Kefa M. Otiso 《GeoJournal》2005,62(1):117-128
Kenya has been promoting equitable urban and regional development since the 1970s despite the lack of a clearly formulated national urban policy or an urban and regional development policy. A key element of the country’s equitable urban and regional development effort is the promotion of secondary cities that would relieve population pressure in the countryside, help to better integrate the country’s rural and urban economies, help to reduce congestion and improve the quality of life in the metropolitan cities of Nairobi and Mombasa, and help increase the modernization spin-off which urban centers provide to the surrounding rural areas. Using recent census and economic survey data, this paper examines the current state of Kenya’s secondary cities in the context of its urban and regional development strategies. The paper finds that: (1) the country’s urban and regional development strategies have failed to work as planned largely because of insufficient devolution of power and fiscal responsibility to municipal and other local government units, (2) the country’s secondary cities are faced with immense challenges that undermine their ability to live up to expectations, (3) some of these cities have significantly grown economically over the last four decades despite immense challenges, and (4) Nairobi’s dominance of Kenya’s economy continues because of policies that unwittingly concentrate investments there. The paper concludes with strategies that could enhance the country’s urban and regional development programs and, in the process, aid the development of its secondary cities.  相似文献   

12.
Kenya has been promoting equitable urban and regional development since the 1970s despite the lack of a clearly formulated national urban policy or an urban and regional development policy. A key element of the country’s equitable urban and regional development effort is the promotion of secondary cities that would relieve population pressure in the countryside, help to better integrate the country’s rural and urban economies, help to reduce congestion and improve the quality of life in the metropolitan cities of Nairobi and Mombasa, and help increase the modernization spin-off which urban centers provide to the surrounding rural areas. Using recent census and economic survey data, this paper examines the current state of Kenya’s secondary cities in the context of its urban and regional development strategies. The paper finds that: (1) the country’s urban and regional development strategies have failed to work as planned largely because of insufficient devolution of power and fiscal responsibility to municipal and other local government units, (2) the country’s secondary cities are faced with immense challenges that undermine their ability to live up to expectations, (3) some of these cities have significantly grown economically over the last four decades despite immense challenges, and (4) Nairobi’s dominance of Kenya’s economy continues because of policies that unwittingly concentrate investments there. The paper concludes with strategies that could enhance the country’s urban and regional development programs and, in the process, aid the development of its secondary cities.  相似文献   

13.
Perception about people’s behaviour during emergencies defines, to a large extent, the course of planning and resource allocation for community emergency response as well as development of mitigation measures. During the past decade, there has been a paradigm shift in the approach to disaster management. A recent trend has been to encourage more community participation as opposed to the top-down approach of the past. It is believed that community participation will bring about a comprehensive and accurate appreciation of people’s perception regarding hazards, risk, vulnerability, and resilience, and this research is an attempt to achieve just that. In order to accomplish our goal, we engaged a group of women that would typically fall into the category of “vulnerable group” in a focus group interview setting. The participants were mainly over 40 years old, the majority with little education, unemployed, facing language barriers, of low income, and reliant on public transit. Many participants identified that they lived in the vicinity of rivers, lakes, railways, or power plants, but did not seem to be aware of their exposure to potential threats—indicating a lack of education and awareness. The most common hazards and mitigation measures they were aware of, included floods (including basement flooding), fire, fire alarm, and smoke detectors. Additionally, illness and loneliness were mentioned as factors contributing to their increased vulnerability, hence reduced resiliency. With the help of the focus group members’ participation, we were able to discuss the importance of communities being aware of their surroundings, available resources and help, and permit them to voice their concerns in order to be able to cope during emergencies. We trust and hope that more community participation will lead to stronger and more resilient cities.  相似文献   

14.
全球气候变化和快速城市化导致的城市水循环过程变化是当前城市水文学研究的热点问题。为综合理解城市水循环演变过程,结合城市水文学的发展历程,剖析水循环过程对快速城市化进程的响应机制。总结了国内外城市化水文效应的主要成果,包括城市化对水循环过程、洪涝灾害、水生态系统以及水资源的影响。系统归纳了城市化水文效应的评估方法和技术手段。针对现有研究中的不足,指出变化环境下城市化水文效应研究面临的主要挑战及关键技术难题,提出未来研究的重点方向,如城市化降水效应的机理、不透水面的分布及有效性评估、城市化与水生态系统的响应关系与综合城市水资源管理及需水预测等。  相似文献   

15.
Suburbanization has been a prominent urban process in the United States since the World War II. It has transformed American cities in profound ways in every single aspect of urban development; from population and wealth distributions, through political organization and affiliations, to the built environment. This paper investigates the link between gated communities and the process of suburbanization in the context of socio-economic inequality. It has been shown time and again in the scholarly literature on suburbanization, that suburban neighborhoods in American cities have been traditionally more affluent and less diverse than central cities. The research on gated communities in the US also shows that they are, on average, more affluent compared to other communities in terms of family income and housing values. Are gated communities then simply a new form of suburban communities? Is the gated community in fact a suburban community with the added element of security features? The paper investigates these questions based on segregation and spatial analyses. The research contributes to the long line of studies on suburbanization, gating and the larger issues of urban inequality.  相似文献   

16.
刘恋  杨帅斌  乔彦松  周鑫  詹涛 《地质学报》2017,91(3):658-667
黑碳是由生物质和化石燃料等燃烧产生的一系列含碳物质,长期广泛分布于土壤、大气等多种载体中,且表现出不同的环境效应。土壤作为一种不可再生的自然资源,是人类生存与发展不可缺少的物质基础,也是支撑城市发展的空间和生态基础。土壤中的黑碳构成土壤有机碳库的重要组分,且影响着土壤肥力、结构、有机污染物等多方面。目前,对黑碳的研究集中在其对环境的影响,我国在这方面的研究开始较晚,特别是对土壤中黑碳的研究还处于起步阶段。本文详细分析了土壤黑碳的可能来源(自然火灾、人类农业活动、化石燃料燃烧以及汽车尾气排放等),概括了常见的土壤黑碳来源辨析方法(黑碳形态特征分析、黑碳/有机碳比值分析、黑碳碳同位素分析),总结了国内外对不同自然环境、不同城市功能区的土壤黑碳研究现状。最后,提出了全球黑碳研究亟待关注和解决的关键问题,以期为将来合理制定控制黑碳排放的相关政策,减缓黑碳对环境质量和人体健康的影响,提供重要的理论依据。  相似文献   

17.
In poor health: Supermarket redlining and urban nutrition   总被引:1,自引:0,他引:1  
Over the past 100 years, ethnic minorities and the poor have become increasingly concentrated and isolated in low-income urban neighborhoods. While the demographic changes in cities are well documented, the parallel history of urban retailing is less well known. Little research has been done on changes in urban food retailing, particularly as they concern the urban poor. As the residential character of urban neighborhoods changed during the 20th century, so did the amenities available in those neighborhoods. The low point for urban retailing was in the 1980s, when cities experienced a net loss of supermarkets even as, nationally, store openings exceeded closings. The trend toward fewer, bigger stores located outside cities has continued to the present. Some critics have referred to this disinclination of large chains to locate in cities as `supermarket redlining'. Changes in food availability are a key element in the changing social conditions of the urban poor and, as good nutrition is critical for good health, a contributing factor in the decline of urban health. This paper will examine changes in urban retail food availability, the impact these changes have had on the health status of the urban poor, strategies utilized by the urban poor to address inadequate access to quality food sources, and the role of supermarkets in distressed communities.  相似文献   

18.
Flood disasters and its consequent damages are on the rise globally. Pakistan has been experiencing an increase in flood frequency and severity along with resultant damages in the past. In addition to the regular practices of loss and damage estimation, current focus is on risk assessment of hazard-prone communities. Risk measurement is complex as scholars engaged in disaster science and management use different quantitative models with diverse interpretations. This study tries to provide clarity in conceptualizing disaster risk and proposes a risk assessment methodology with constituent components such as hazard, vulnerability (exposure and sensitivity) and coping/adaptive capacity. Three communities from different urban centers in Pakistan have been selected based on high flood frequency and intensity. A primary survey was conducted in selected urban communities to capture data on a number of variables relating to flood hazard, vulnerability and capacity to compute flood risk index. Households were categorized into different risk levels, such as can manage risk, can survive and cope, and cannot cope. It was found that risk levels varied significantly across the households of the three communities. Metropolitan city was found to be highly vulnerable as compared to smaller cities due to weak capacity. Households living in medium town had devised coping mechanisms to manage risk. The proposed methodology is tested and found operational for risk assessment of flood-prone areas and communities irrespective of locations and countries.  相似文献   

19.
This article sets out an agenda for research that (re)connects research on children’s geographies and childhood studies with studies of spatial literacy. Research on children’s environmental cognition and, latterly, spatial literacy, has been artificially and problematically separated from the majority of research in childhood studies. Our fundamental aim in this article is to argue for – and to evidence – greater attention to how spatial literacy and children’s everyday lives are embedded in one another. To support our broader call for a synthetic research agenda, we draw on some more focussed, qualitative empirical material taken from a large-scale project about children’s mobilities and everyday lives in newly-built urban communities. Our analysis focuses upon children’s interpretations of Global Positioning Systems (GPS) tracks of their mobilities, set against a background of Google Earth imagery. In doing so, we showcase one suite of ways in which research on environmental cognition and children’s geographies might proceed together. We demonstrate that children not only displayed analytical skills (for instance, in relation to scaling effects and pattern recognition) but that many also exercised higher-level, critical analysis, especially in relation to errors on Google Earth outputs. Simultaneously, we interrogate the recursive articulation of a range of qualitative indicators of spatial literacy, with children’s everyday mobilities, routines, emotions and memories. The paper analyses how new conceptual languages and technologies being propounded by spatial literacy scholars could afford a more enriched understanding of key contemporary concerns for children’s geographers, and, recursively, what spatial literacy scholars might gain from engaging with (especially qualitative) research prompted by those concerns.  相似文献   

20.
Bus fare subsidy, the difference between an economic fare charged by a bus operator and the amount paid by Black passengers, has played a vital role in the formation of the apartheid city in South Africa. Until 1986 employers paid transport levies on a weekly or monthly basis whilst the Government budgeted the contribution through Department of Transport vote. Transport subsidies reveals that subsidies were used to foster and facilitate the spatial organisation of urban areas. Subsidies were strongly associated with the geographical dislocation of Black communities from the centre of urban areas to the urban periphery. Subsidies first affected Black male workers in Johannesburg and a few geographical areas but were later extended to include African women, Coloureds and Indians. The theme that emerges from this paper is that the state used subsidies as one of the myriad strategies excluding Blacks politically, controlling them socially and making them dependent economically.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号