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811.
Abstract

This paper addresses the relevance of the demand side for the achievement of sustainable transport in urban areas. The underlying thesis is that a better understanding of user habits, perceptions and attitudes with its specific dynamics is essential for a successful design of targeted transport policies. In line with this, the paper at hand is based on research that aims at improving the knowledge of urban-transport-related habits and attitudes of young adults. The results of three interview meetings that were held in Karlsruhe, Budapest, and Copenhagen with participants aged between 20 and 30 are presented. Background of the interviews is a range of studies that indicate that young people in urban areas seem to be less interested in cars than the generation before. And indeed, the interview meetings reveal that participants had a rather pragmatic attitude towards transport modes. They wished a transport system that is flexible, convenient and cheap. Despite many differences, most participants showed rather positive attitudes towards policies supporting alternatives to car-based transport. However, it will be crucial for policy shaping to what extent the observed behaviour patterns and attitudes will persist over time.  相似文献   
812.
生物质能是当前能源和生态环境领域研究的热点。分析和研究,指出了生物质能在国内外的发展现状和趋势。全、实现可持续发展意义重大。本文对生物质能的资源分类和利用方式进行了明确了开发利用生物质能源,对保障国家能源安  相似文献   
813.
对CDM市场的项目类型进行了归纳与分析,总结了CDM项目类型与项目注册过程中的问题,对CDM项目交易市场的现状及制度进行了探讨,并提出了相关建议。  相似文献   
814.
While it is true that tourism is one of the main driving forces behind economic growth in several world regions, it is also true that tourism can have serious negative environmental impacts, especially with regard to water resources. The tourist water demand can generate big problems of sustainability, mainly in those regions where water is scarce, as occurs in most coastal and small island destinations where a large part of world tourism is concentrated. Given the shortage of literature on the subject, further research into the tourist water demand is required, with particular attention to the hotel sector, since hotels are the most popular option for tourists, displaying higher levels of water consumption. The main purpose of this study is to develop a model to analyse hotel water consumption at a mature sun and sand destination with a strong seasonal pattern and scarcity of water; characteristics shared by some of the world's main tourist destinations. Our model includes a set of different hotel variables associated with physical, seasonal and management-related factors and it improves on the capacity to explain water consumption at such destinations. Following a hierarchical regression methodology, the model is empirically tested through a survey distributed to managers of a representative sample of hotels on the island of Mallorca. From the obtained results, interesting recommendations can be made for both hotel managers and policy makers. Among these, it should be highlighted that the strategic move contemplated by many mature destinations towards a higher quality, low-season model could have significant negative effects in terms of the sustainability of water resources. Our results also conclude that managerial decisions, like the system of accommodation that is offered (i.e. the proliferation of the "all-inclusive" formula, both at mature and new destinations), could give rise to the same negative effect. Development of water saving initiatives (usually introduced in response to demand-based factors), also reveals significant effects over water consumption. Finally, other key factor in explaining hotel water consumption is the management system under which the hotel is run.  相似文献   
815.
Light pollution is one of the most rapidly increasing types of environmental degradation. Its levels have been growing exponentially over the natural nocturnal lighting levels provided by starlight and moonlight. To limit this pollution several effective practices have been defined: the use of shielding on lighting fixture to prevent direct upward light, particularly at low angles above the horizon; no over lighting, i.e. avoid using higher lighting levels than strictly needed for the task, constraining illumination to the area where it is needed and the time it will be used. Nevertheless, even after the best control of the light distribution is reached and when the proper quantity of light is used, some upward light emission remains, due to reflections from the lit surfaces and atmospheric scatter. The environmental impact of this "residual light pollution", cannot be neglected and should be limited too. Here we propose a new way to limit the effects of this residual light pollution on wildlife, human health and stellar visibility. We performed analysis of the spectra of common types of lamps for external use, including the new LEDs. We evaluated their emissions relative to the spectral response functions of human eye photoreceptors, in the photopic, scotopic and the 'meltopic' melatonin suppressing bands. We found that the amount of pollution is strongly dependent on the spectral characteristics of the lamps, with the more environmentally friendly lamps being low pressure sodium, followed by high pressure sodium. Most polluting are the lamps with a strong blue emission, like Metal Halide and white LEDs. Migration from the now widely used sodium lamps to white lamps (MH and LEDs) would produce an increase of pollution in the scotopic and melatonin suppression bands of more than five times the present levels, supposing the same photopic installed flux. This increase will exacerbate known and possible unknown effects of light pollution on human health, environment and on visual perception of the Universe by humans. We present quantitative criteria to evaluate the lamps based on their spectral emissions and we suggest regulatory limits for future lighting.  相似文献   
816.
绿色文化探析   总被引:9,自引:0,他引:9  
绿色文化以生态学理论为指导,以可持续发展为根本目标,是人类思想领域的又一次深刻劳动保险。从绿色思想,绿色科技到人们日常生活密切相关的绿色工业产品,绿色食品,绿色消费,绿色包装,绿色文学 ,绿色文化已渗透到人类社会生活的各个领域。  相似文献   
817.
Historical changes in the environment of the Chinese Loess Plateau   总被引:2,自引:0,他引:2  
Historical records from the past 2000 years indicate that the vegetative cover of the Loess Plateau has declined significantly with time. The decline in vegetative cover seems closely related to increased rates of soil erosion as well as the increased frequency of natural disasters such as floods, droughts and dust storms. The condition of the environment and its relationship with development is a serious problem as the Chinese government searches for ways to improve the living standard of people in the region. The purpose of this study is to outline historical changes in the vegetation and environmental conditions of the Loess Plateau. Although we believe that current population pressure of the Loess Plateau is becoming unsustainable, our objective is not to be overly pessimistic in regards to the future development of the region. Instead, our purpose is to increase the awareness of environmental conditions in the region and to encourage the implementation of policies that will promote sustainable development of the Loess Plateau.  相似文献   
818.
AB法的发展及其在三峡库区的应用前景   总被引:1,自引:0,他引:1  
结合三峡库区水质,经济状况,在综合分析AB法特点的基础上,指出AB法在三峡库区有较广阔应用前景。  相似文献   
819.
This article presents an assessment of the effectiveness of national and international energy policies directed toward the objectives of sustainable development contained in Agenda 21. Following a brief overview of energy and transport sector trends over the past ten years, the article discusses whether and to what extent energy policies for sustainable development have impacted on poverty reduction, energy security, equitable access to energy, and transition to a more efficient and environmentally sound energy system.
The impact of policies is assessed considering that such a transition involves appropriate combinations of energy efficient technologies and usage patterns, wider use of renewable energy, and gradual induction of advanced energy technologies. The article then examines the extent to which such policies have been based on integrated assessments of the needs and priorities in economic growth, social development and environmental protection and identifies some of the main constraints and barriers hampering the implementation of energy for sustainable development. The article also examines whether decision-making processes ensure multi-stakeholder participation in policy development and support a fair sharing of commitments, responsibilities and benefits among the participating stakeholders in policy implementation. Selected case studies of policies that have made a tangible difference in promoting energy for sustainable development are outlined.
Finally the article discusses the challenges facing energy for sustainable development and discusses various options to accelerate the implementation of its goals.  相似文献   
820.
This paper presents a framework for understanding energy issues in the context of sustainable development. It posits that there are three important ways in which energy is related to sustainable development: (a) energy as a source of environmental stress, (b) energy as a principal motor of macroeconomic growth and (c) energy as a prerequisite for meeting basic human needs. These three dimensions correspond to the three dimensions of the often-used triangle of sustainable development: environmental, economic, and social. Using this framework, the paper traces how successive environmental summits at Stockholm (1972), Rio de Janeiro (1992) and Johannesburg (2002) have dealt with energy issues. It identifies a slow, surprising and important evolution of how energy issues have been treated at these global discussions. Energy has received increasing prominence at these meetings and become more firmly rooted in the framework of sustainable development. Stockholm was primarily concerned with the environmental dimension, Rio de Janeiro focused on both the environmental and economic dimensions, and the major headway made at Johannesburg was the meaningful addition of the social dimension and the linking of energy issues to the UN's Millennium Development Goals.  相似文献   
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