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 265 毫秒
1.
Third World cities have been suffering from many problems notably slums, squatter housing, unemployment and so on. The aim of this study is to discuss the process and means of transforming rural life so as to create better opportunities and enhance the living conditions in the countryside. It is suggested that this approach would retain a substantial part of the rural population in the rural areas, thus avoiding the urban problems and chaotic unplanned development.  相似文献   

2.
Impact of Urban Sprawl on Water Quality in Eastern Massachusetts,USA   总被引:5,自引:0,他引:5  
A study of water quality, land use, and population variations over the past three decades was conducted in eastern Massachusetts to examine the impact of urban sprawl on water quality using geographic information system and statistical analyses. Since 1970, eastern Massachusetts has experienced pronounced urban sprawl, which has a substantial impact on water quality. High spatial correlations are found between water quality indicators (especially specific conductance, dissolved ions, including Ca, Mg, Na, and Cl, and dissolved solid) and urban sprawl indicators. Urbanized watersheds with high population density, high percentage of developed land use, and low per capita developed land use tended to have high concentrations of water pollutants. The impact of urban sprawl also shows clear spatial difference between suburban areas and central cities: The central cities experienced lower increases over time in specific conductance concentration, compared to suburban and rural areas. The impact of urban sprawl on water quality is attributed to the combined effects of population and land-use change. Per capita developed land use is a very important indicator for studying the impact of urban sprawl and improving land use and watershed management, because inclusion of this indicator can better explain the temporal and spatial variations of more water quality parameters than using individual land use or/and population density.  相似文献   

3.
Based on research in peri-urban areas, this paper explores questions of water justice in the context of emerging global cities. With the growth of large cities, authorities focus on meeting their water needs through infrastructure expansion and supply augmentation. The changing water needs and priorities of peri-urban locations, which provide land and water for urban expansion, receive scant attention. This paper looks at changing patterns of water use between rural and urban uses, based on research in peri-urban Gurgaon, an emerging outsourcing and recreation hub of North West India. It describes the diversity of ways in which peri-urban residents lose access to water as the city expands. These processes raise important questions about water justice, about the politics of urban expansion, and the implicit biases about whom these cities are meant for.  相似文献   

4.
Poverty is rampant in the rural areas of Pakistan, where people are in a state of deprivation with regard to incomes, clothing, housing, healthcare, education, sanitary facilities and human rights. Agriculture generates nearly 20.9 percent of the country's GDP and provides employment for 43.4 percent of its workforce. Most importantly, 65.9 percent of the population living in rural areas is directly or indirectly dependent on agriculture for their livelihood. Rising population, shrinking agricultural land, increasing demand for water resources, widespread land degradation and inadequate infrastructure appear to be major concerns of the agriculture sector in Pakistan. An attempt has been made to examine the population growth–agriculture growth–poverty alleviation linkage. It is argued that agriculture will continue to be one of the most important sectors of Pakistan's economy for years to come. To alleviate poverty, it is suggested that Pakistan enhance the productivity of the agriculture sector through the provision of a series of inputs including provision of easy credit to the small farmer, availability of quality fertilizers and pesticides, tractor and harvester services, improvement in the effectiveness of the vast irrigation system and, finally, farmer education. It is concluded that the high rate of population growth needs to be curbed for increased agricultural productivity to have any significant effect on poverty in rural areas of Pakistan.  相似文献   

5.
Summary The grave shortage of land suitable for development has always been a major constraint on urbanisation in Hong Kong. Rather lax or inappropriate planning controls in the past have resulted in haphazard city growth, leaving extensive areas of densely-packed tenement slums. Recent sluggish attempts at urban renewal have brought little relief. The objectives of environmental planning to rejuvenate the old districts are assessed in relation to their limitations and potential. The problems and opportunities of employing comprehensive redevelopment to upgrade environmental quality with reference to building stocks in the pre-war and post-war private residential, public housing and obsolete industrial sectors are evaluated. The prospects of environmental improvement through new institutional framework and legislative measures are discussed.  相似文献   

6.
本文旨在对中国各城市高铁出行情况与人群环境健康影响进行大数据分析。文中的环境健康影响指将高铁出行过境次数引入经典泊松回归模型,进而直接得到各城市人群环境健康受到高铁出行的影响。另外,为了更好地分析高铁出行下的人群环境影响,笔者在计算环境影响指数时将受影响人群分为高铁沿线城市本地人群(PED)和过境人群(TPED)。最后总结分析了全国范围内环境健康受过境次数影响的程度大小。通过计算结果可得,华北、华中、四川盆地等地区的大城市,人口多、过境车次多、空气质量相对较差,PED和TPED值较高。华中、华南、西南边境地区城市的空气质量较好,PED和TPED值较低。另外,就特定高铁线路的环境健康影响而言,京津、郑西高铁沿线的PED和TPED值较高;广深、合福、沪昆高铁沿线的PED和TPED值较低。  相似文献   

7.
Urban green/blue spaces are put under pressure as urban areas grow, develop and evolve. It is increasingly recognized, however, that green/blue spaces provide important ecosystem services, stimulate higher real estate prices and prevent flooding problems. This paper aims to assess and compare the socio-economic impacts of potential green/blue space, urban residential and road infrastructure development scenarios in the Lyon Confluence project area (France), using the Sustainable Urbanizing Landscape Development (SULD) hedonic pricing simulation model. Results show four major tendencies regarding the value-added of green/blue spaces in urban landscapes: (1) cities become more compact; (2) population densities increase; (3) real estate values rise; and (4) demographic distribution patterns change. The magnitude of these impacts depends, however, on the quality and size of the intervention, the social classes attracted to the intervention area and on the location of the intervention relative to existing residential areas, urban centres, road infrastructure and environmental amenities.  相似文献   

8.
ABSTRACT: Typically, infrastructure agencies build massive water projects to serve expanding populations in emerging country cities, but collect and treat only a fraction of the resulting wastewater. This effluent often overwhelms existing sewerage systems and fouls waterways. Cleaning urban waterways requires large investments over long terms and the political will to make and sustain them. This challenge - difficult in advanced countries - becomes daunting with the scarce resources and weak institutions typical of emerging countries. This paper presents a framework to structure such a strategy, and applies it to Madras, India. It consists of three parts: (1) setting a vision through a participatory process; (2) macro investments mainly in wastewater treatment that use least-cost methods; and (3) micro investments in small projects that involve local people and galvanize public support. The macro investment, $350 million for Madras, appears very large, but averages out to $66 per capita, far below the $1,000-$2,000 typical of advanced country cities. Micro projects to be undertaken by Non-Governmental Organizations (NGOs) included an independent wastewater monitoring program, sanitary upgrading of slums along waterways banks, a cattle waste demonstration project, and an industrial pollution survey. Together, a macro/micro strategy promises the funding and political will to achieve a balanced vision of waterways quality.  相似文献   

9.
The total protected area designated by different countries varies enormously as does the balance within that area between natural and cultural landscapes. It is argued that population density and degree of urbanisation affect the area meriting protection and also the demand for protection, and that these, in turn, affect the area that is protected. Twenty-two European countries are classified into 4 groups (low population density rural; low population density urban; intermediate population density; and high population density). The areas protected by countries in each group and the extent to which they protect the natural as opposed to the cultural are substantially as predicted.  相似文献   

10.
Sustainable urban water infrastructure planning is vital for all cities in developing countries, where rapid urbanization has exacerbated the increasingly burdened environment. Water sustainability is a prerequisite for economic growth, social equity, and living quality in urban areas. This paper documents the current challenges and summarizes the solutions adopted in water infrastructure planning and management. Then, case studies of how multilateral financial institutions have promoted sustainable water infrastructure planning through economic appraisal and the novel approaches adopted for sustainable water infrastructure planning and asset management, are presented for the three cities of Jiaozhou, Cixi, and Fangchenggang. Conclusions are made based on the comparison and analysis of the experiences drawn from the case studies of how economic analysis could help promote sustainable water infrastructure planning and management. It is illustrated that economic analysis that considers ecosystem services supply should be employed more in water infrastructure planning, operation, and management in China.  相似文献   

11.
Rapid urbanisation, lack of proactive planning and improper allocation of resources may result in socio-economic disparity among and within cities, causing social unrest and environmental injustice in the neighbourhoods. This study aims to examine whether the planning standards for housing schemes in Pakistan are able to maintain equitable access to green spaces within the cities. Ten residential sites in Sheikhupura city with different housing unit sizes and densities were selected for the study. The supply of urban green infrastructure in housing scheme has been assessed: (i) by comparing the percentage of green spaces, including community parks and open spaces and street landscape; and (ii) by calculating per dwelling unit and per capita share of green spaces. These indicators have been studied against the housing density and population density of the schemes by applying correlation and linear regression models. The results show that all the housing schemes plans provide for similar amounts of green space as a percentage of total area. The per capita share of green spaces is very low in high-density areas, but interestingly, the street landscape has a higher potential to contribute to the overall landscape in high-density neighbourhoods, compensating for low per capita green space. Housing unit density and population density must be incorporated in planning standards so planners can effectively devise a mix of community parks, street landscape and private green spaces to help maintain per capita green spaces, and hence environmental resource equality in different parts of the city.  相似文献   

12.
Whether a city develops into a more compact one with a higher density or a more sprawling one may affect multiple aspects of the urban environment, including ecosystem health, greenhouse gas emissions, and quality of life. Using panel data gathered from China's cities from 2000 to 2010, we take advantage of the significant variation in the temporal change of density across cities to estimate the relationship between gross urban population density and multiple indicators of urban greenness. Fixed‐effects estimates support the widely held belief that density improves air quality and reduces the per capita carbon footprint. Results also suggest that higher density reduces the growth of road infrastructure and vehicle ownership and promotes walking. While density often translates into proximity and accessibility, higher density does reduce a city's per capita urban park and green space. This study strengthens the urban policy and planning literature with much needed longitudinal evidence. Our overall findings support higher density as opposed to lower density urban development in China.  相似文献   

13.
Loss of the green belts in the cities as an antecedent outcome of haphazard and irregular urbanization as one of the principle factors has a negative bearing on the socio ecological services that nature entails. Our paper represents the conditions under which the contemporary statist conservationist efforts to preserve the urban protected areas (PAs) in India induces a marginal existence and livelihood vulnerability upon the survival of the population residing within these PAs. A recent survey to Sanjay Gandhi National Park in Mumbai reflects the ways in which a politics of conservation operates not only in the rural regions but also in cities, in highly inequitable and fabricated ways. This has consequently affected the impoverished, disempowered and impecunious inhabitants who comprise a considerable segment of population in cosmopolitan Mumbai, residing within the PAs. The present article assesses the ways in which in metropolises, PAs by definition determine jurisdictions and exercise rights to exclude the social groups who are marginal and less powerful. This is to preserve a pristine people free aesthetic environment in cities, for which there is an increasing demand from the local elite. The results of the study indicate the socio ecological aspects of the conservation politics in the city of Mumbai. The emergent consequences are in terms of the questions of universal rights to the PAs or reflecting an elitist provision of environmental integrity to the privileged visitors in the city.  相似文献   

14.
Much of Sub‐Saharan Africa is burdened with water scarcity and poverty. Continentally, less than four percent of Africa's renewable water resources are withdrawn for agriculture and other uses. Investments in agricultural water management can contribute in several ways to achieving the Millennium Development Goals of eradicating extreme poverty and hunger and ensuring environmental sustainability. Increased yield and cropping area and shifts to higher valued crops could help boost the income of rural households, generate more employment, and lower consumer food prices. These investments can also stabilize output, income and employment, and have favourable impacts on education, nutrition and health, and social equity. Investments in agricultural water management can cut poverty by uplifting the entitlements and transforming the opportunity structure for the poor. The overall role of investments in agricultural water management in eradicating hunger and poverty is analyzed. This paper contributes to the present debate and efforts to identify strategies and interventions that can effectively contribute to poverty reduction in Africa. It provides an overview of population growth, malnutrition, income distribution and poverty for countries in three case study river basins — Limpopo, Nile, and Volta. With discussions on the contribution of agriculture to national income and employment generation, the paper explores the linkages among water resources investments, agricultural growth, employment, and poverty alleviation. It examines the potential for expansion in irrigation for vertical and horizontal growth in agricultural productivity, via gains in yield and cropping area to boost the agricultural output. Factors constraining such potential, in terms of scarcity and degradation of land and water resources, and poor governance and weak institutions, are also outlined. The paper argues that increased investments in land and water resources and related rural infrastructure are a key pathway to enhance agricultural productivity and to catalyze agricultural and economic growth for effective poverty alleviation.  相似文献   

15.
This paper compares the public attitudes of three southern Chinese cities/towns, namely Guangzhou, Dongguan, and Yuanzhou on waste recycling and avoidance, and the New Environmental Paradigm (NEP). The latter describes the concept of treating the resources and the ecosystems on Earth as things having their own rights rather than being subordinate and subservient to humans. These three places are chosen to represent areas in different stages of urbanization in the Guangdong province. As Hong Kong is also a southern Chinese city, where data of similar nature are available, comparison with Hong Kong is also made. It was found that the support for source separation of household waste in the rural and urban areas in mainland China was greater than that found in Hong Kong. Concerning actual practices on waste separation, about 85% of the respondents in the cities and almost all of the rural household surveyed have the habit of saving up and selling the recyclables. It is estimated that about 11-13% of the household waste was diverted in such a way. This is higher than the estimated 8% household waste recovery rate of Hong Kong. The majority of the respondents in the three surveyed cities have recovered household recyclables in the past but with higher family incomes, it was now less common. On the contrary, the lower income group tended to recover greater portion of their waste for selling to the waste depots. These findings have implications on the future waste management policy formulation in China. Regarding the acceptance of the New Environmental Paradigm, it was found that the rural population scored better than the urban population and they tended to agree more frequently with the NEP. However, the rural population perceives a greater potential for industrial and urban development without dampening environmental quality. It was also found that the NEP scores of the mainland Chinese are higher, in general, than their Hong Kong counterparts as measured in early 1990s. Insufficient public support has often been a concern for source separation programmes in all countries despite the obvious waste management benefits of recycling. This study shows that there is overwhelming support for source separation of waste in Mainland China, whether it is in rural or urban communities, and that most people are already undertaking source separation due to the redemption value of the recyclables. Therefore, for policy-makers, the concern should not be on whether the public knows how to separate the waste but rather on how to motivate them to separate waste for the good of society, and how to maintain an effective market for recyclables.  相似文献   

16.
Urbanisation produces numerous changes in the natural environments it replaces. The impacts include habitat fragmentation and changes to both the quality and quantity of the stormwater runoff, and result in changes to hydrological systems. This review integrates research in relatively diverse areas to examine how the impacts of urban imperviousness on hydrological systems can be quantified and modelled. It examines the nature of reported impacts of urbanisation on hydrological systems over four decades, including the effects of changes in imperviousness within catchments, and some inconsistencies in studies of the impacts of urbanisation. The distribution of imperviousness within urban areas is important in understanding the impacts of urbanisation and quantification requires detailed characterisation of urban areas. As a result most mapping of urban areas uses remote sensing techniques and this review examines a range of techniques using medium and high resolution imagery, including spectral unmixing. The third section examines the ways in which scientists and hydrological and environmental engineers model and quantify water flows in urban areas, the nature of hydrological models and methods for their calibration. The final section examines additional factors which influence the impact of impervious surfaces and some uncertainties that exist in current knowledge.  相似文献   

17.
ABSTRACT

Most institutions and industrial actors believe that district heating infrastructure can play a key role in accelerating the transition to low-carbon energy systems. In this article we test this belief in Italy, starting from a census of all existing plants, subdivided by sources of supply and business organization models. We isolate two types of district heating (urban and rural) and find that they are different with respect to their approaches to energy transition. In rural areas, networks constitute systems that can empower the local techno-institutional complex to achieve a technological leap. Set in a pre-existing social network, district heating reinforces a sense of community and facilitates the involvement of various local players in a collective project. In the case of biomass, we are faced with local systems that have almost completed the transition with regard to the production of thermal and sometimes electric energy. In urban areas, on the other hand, networks represent functional devices for the stabilization of the techno-institutional complex. They allow cities to work on the circularity of some economies, generating added value from the same factors of production. The discrepancy between urban and rural contexts thus highlights the need to consider the ambivalence of district heating technology.  相似文献   

18.
Urbanisation is truly a global phenomenon. Starting at 39% in 1980, the urbanisation level rose to 52% in 2011. Ongoing rapid urbanisation has led to increase in urban greenhouse gas (GHG) emissions. Urban climate change risks have also increased with increase in climate-induced extreme weather events and more low-income urban dwellers living in climate sensitive locations. Despite increased emissions, including GHGs and heightened climate change vulnerability, climate mitigation and adaptation actions are rare in the cities of developing countries. Cities are overwhelmed with worsening congestion, air pollution, crime, waste management, and unemployment problems. Lack of resources and capacity constraints are other factors that discourage cities from embarking on climate change mitigation and adaptation pathways. Given the multitude of problems faced, there is simply no appetite for stand-alone urban climate change mitigation and adaptation policies and programmes. Urban mitigation and adaptation goals will have to be achieved as co-benefits of interventions targeted at solving pressing urban problems and challenges. The paper identifies administratively simple urban interventions that can help cities solve some of their pressing service delivery and urban environmental problems, while simultaneously mitigating rising urban GHG emissions and vulnerability to climate change.  相似文献   

19.
South Asia is one of the most densely populated regions of the world, where despite a slow growth, agriculture remains the backbone of rural economy as it employs one half to over 90 percent of the labor force. Both extensive and intensive policy measures for agriculture development to feed the massive population of the region have resulted in land degradation and desertification, water scarcity, pollution from agrochemicals, and loss of agricultural biodiversity. The social and ethical aspects portray even a grimmer picture of the region with growing poverty mainly, amongst small farmers, food scarcity, and overall poor quality of life. This article reviews the historical perspective of agriculture development in the region and gives a panoramic view of the policy initiatives and their environmental as well as social and ethical spin-offs. The aim is to explore the environmental and ethical dimensions of the agricultural development in South Asia and recommend a holistic approach in formulating plans and programs to combat environmental degradation, hunger, and poverty resulting from unsustainable agricultural practices.  相似文献   

20.
ABSTRACT

Smart and eco-cities have become important notions for thinking about urban futures. This article contributes to these ongoing debates about smart and eco-urbanism by focussing on recent urbanisation initiatives in Asia. Our study of India’s Smart Cities Mission launched under the administration of Narendra Modi and China’s All-In-One eco-cities project initiated by Xi Jinpin unfolds in two corresponding narratives. Roy and Ong’s [2011. Worlding Cities: Asian Experiments and the Art of Being Global. Oxford: Wiley-Blackwell] “worlding cities” serves as the theoretical backdrop of our analysis. Based on a careful review of a diverse set of academic literature, policy and other sources we identify five process-dimensions for analysing the respective urban approaches. We show how the specific features of China’s and India’s urban focus, organisation, implementation, governance and embedding manifest both nations’ approaches to smart and eco-urbanism. We argue that India’s Smart City Mission and China’s All-in-One project are firmly anchored in broader agendas of change that are set out to transform the nation and extend into time. The Indian Smart City Mission is part of a broader ambition to transform the nation enabling her “smart incarnation” in modernity. Smart technologies are seen as the key drivers of change. In China the framework of ecological civilisation continues a 5000-year historical tradition of civilisation excellence. By explicitly linking eco-urbanism to the framework, eco-cities become a means to enact ecological civilisation on the (urban) ground.  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