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31.
This paper aims to identify the main driving force for changes of total primary energy consumption in Beijing during the period of 1981-2005. Sectoral energy use was investigated when regional economic structure changed significantly. The changes of total primary energy consumption in Beijing are decomposed into production effects, structural effects and intensity effects using the additive version of the logarithmic mean Divisia index (LMDI) method. Aggregate decomposition analysis showed that the major contributor of total effect was made by the production effect followed by the intensity effect, and the structural effect was relatively insignificant. The total and production effects were all positive. In contrast, the structural effect and intensity effect were all negative. Sectoral decomposition investigation indicated that the most effective way to slow down the growth rate of total primary energy consumption (TPEC) was to reduce the production of the energy-intensive industrial sectors and improving industrial energy intensity. The results show that in this period, Beijing's economy has undergone a transformation from an industrial to a service economy. However, the structures of sectoral energy use have not been changed yet, and energy demand should be increasing until the energy-intensive industrial production to be reduced and energy intensity of the region reaches a peak. As sequence energy consumption data of sub-sectors are not available, only the fundamental three sectors are considered: agriculture, industry and service. However, further decomposition into secondary and tertiary sectors is definitely needed for detailed investigations.  相似文献   
32.
This paper explores the status of sustainable development in small island developing states (SIDS), through the presentation of a case study on the Maldives, which is a typical small island developing state in the Central Indian Ocean. At the outset, a brief history of sustainable development as related to SIDS on the international agenda is outlined, starting from Rio to Barbados to Johannesburg. SIDS are expected to face many challenges and constraints in pursuing sustainable development due to their ecological fragility and economic vulnerability. It is the position of this paper that issues related to environmental vulnerability are of the greatest concern. A healthy environment is the basis of all life-support systems, including that of human well-being and socio-economic development. Priority environmental problems are: climate change and sea-level rise, threats to biodiversity, threats to freshwater resources, degradation of coastal environments, pollution, energy and tourism. Among these, climate change and its associated impacts are expected to pose the greatest threat to the environment and therefore to sustainable development. For small islands dependent on fragile marine ecosystems, in particular on coral reefs, for their livelihoods and living space, adverse effects of climate change such as increased frequency of extreme weather events and sea-level rise will exacerbate the challenges they already face. It is concluded that the paper path from Rio to Barbados to Johannesburg has made significant progress. However, much remains to be done at the practical level, particularly by the developed countries in terms of new and additional efforts at financial and technical assistance, to make sustainable development a reality for SIDS.  相似文献   
33.
This report summarizes the results of two studies of electricity supply for Europe (EU), the Middle East (ME) and North Africa (NA) up to the year 2050. It shows that a transition to competitive, secure and sustainable supply of electricity and water is possible using renewable energy sources, efficiency gains and fossil fuel backup for balancing power. A strong cooperation between the EU and MENA for the market introduction of renewable energy and the interconnection of the electricity grids by high-voltage direct-current transmission are keys to the success and survival of the whole region. However, the necessary measures will take at least two decades to become effective. Therefore, adequate policy and economic frameworks for their realization must be introduced immediately. The importance of sustainable energy for the security of freshwater supplies in MENA is also described.
Hans Müller-SteinhagenEmail:
  相似文献   
34.
China has witnessed rapid economic development since 1978, and during the time, energy production and consumption developed at a tremendous speed as well. Energy efficiency which can be measured by energy consumption per unit of GDP, however, experienced continuous decrease. Theoretically, the change of energy efficiency can be attributed to industry structural change and technological change. In order to explain the transformation of Chinese energy efficiency, we adopt logarithmic mean Divisia index techniques to decompose changes in energy intensity in the period of 1994-2005. We find that technological change is the dominant contributor in the decline of energy intensity, but the contribution has declined since 2001. The change in industry structure has decreased the energy intensity before 1998, but raised the intensity after 1998. Decomposed technological effects for all sectors indicate that technological progresses in high energy consuming industries such as raw chemical materials and chemical products, smelting and pressing of ferrous metals, manufacture of non-metallic mineral products and household contribute are the principal drivers of China's declining energy intensity.  相似文献   
35.
In recent years, scientists have been increasingly interested in the energy embodied in traded goods among countries. In this article, the direct energy intensities in various economic sectors of China were calculated with the data of energy consumption and output value of each sector, and the input-output table was used to estimate the external energy consumption. The total energy intensity of all sectors was then obtained. From the data of international trade, the energy embodied in goods trade of China was estimated for the period of 1994-2001. During this period, the average energy intensity of imported goods was always higher than that of exported ones. As a country with a surplus in international goods trade, China actually imported net embodied energy in the past few years. The net embodied energy imported was at the same magnitude of the imported energy in the form of fossil fuels.  相似文献   
36.
Food production has to be increased in a sustainable way to meet the future global demand. A key position is attributed to developing countries. A deepened understanding of their agricultural regions with specific resource endowments and constraints is therefore crucial. In this study we propose a methodology based on material flux analysis (MFA) to assess the resource potentials and limitations of a Nicaraguan agricultural region. We focus on current regional and farm resource management and explore them under two scenarios. Indicators are nitrogen and the degrees of self-sufficiency (DSS) for energy, and the staples maize and beans. As data is scarce, most information is based on interviews with farmers of four categories and key persons, and on literature. The results show that nitrogen management does not differ considerably among categories. Nitrogen is mined mostly from staple plots. Self-sufficiency for beans is given in an average year. Yet, landless and small farmers neither produce enough maize for autoconsumption, nor are they self-sufficient for firewood. Energy supply is also the core problem of the region, since the DSS is 70%. Soil nitrogen stocks last at most for three more generations. Analyses with the scenario technique show that: (a) Unlimited population growth has serious consequences in the near future e.g. severe shortage of energy and food. (b) Alternative farming systems are possible, but they require reducing the population by a factor 2, and thus the creation of jobs in a Hinterland. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
37.
能源在社会经济发展中具有重要作用。随着能源消耗量剧增,能源供需矛盾、环境问题日益突出,研究区域能源强度变化具有重要的现实意义。采用Laspeyres因素分解法,定量分析江苏省和安徽省的产业结构和产业效率对能源强度的影响。研究发现:(1)安徽省的能源强度高于江苏省的能源强度,不过差距在逐渐变小,利用重标极差法预测未来两省的能源强度会逐渐趋同;(2)江苏省的产业结构发展有减小能源强度的趋势,不过作用过程有波动;产业效率有利于降低能源强度;(3)安徽省的产业结构有助于增加能源强度,作用趋势还在增大,产业效率有利于降低能源强度,降低作用大于江苏省。因此本文提出目前同样的投入应该偏向欠发达地区或能源强度较高地区,这有利于快速取得降低能源强度的成效.  相似文献   
38.
我国城市间客运交通能源消耗趋势的分解   总被引:2,自引:0,他引:2  
随着我国城镇化水平不断提高,城市作为重要的交通网络节点,其衔接交通运输线路、产生和承担客货流转换的功能日益显著。定量地探讨城市间客运交通能源消费变化的影响因素对于我国未来城市间客运交通能源需求的研究及温室气体减排具有重要意义。本文采用终端能源需求MAED模型,对我国城市间客运交通能耗的历史基期数据进行处理,同时对未来能耗进行预测,在形成ASIF结构的数据基础上,利用对数平均迪氏指数法(Logarithmic Mean Index,LMDI)对城市间客运交通能耗的活动效应、结构效应和强度效应进行分解分析。结果表明,从历史数据来看,我国"十五"期间城市间客运交通能耗的快速增加同时取决于客运周转量的增加、客运交通模式和能耗强度的转变,若延续这一发展趋势,我国中长期城市间客运交通模式将快速增长。未来城市间轨道交通网络的发展和高效利用及交通节能减排政策的落实将是促进能源消耗增速降低的可能选择。  相似文献   
39.
This paper aims to estimate the effects of changing life style and consumption demands driven by income growth and urbanization on increase of energy requirements in China, and es-timate the impacts of improvement in household consumption on mitigating energy requirements towards 2020, based on input-out-put analysis and scenarios simulation approach. The result shows that energy requirement per capita has increased by 159% for urban residents and 147% for rural residents from 1995 to 2004. Growth in household consumption driven by income growth and urbanization may induce a successive increase in energy require-ments in future. Per capita energy requirements of urban residents will increase by 240% during 2002-2015 and 330% during 2002-2020. Urbanization might lead to 0.75 billion ton of increment of energy requirements in 2020. About 45%-48% of total energy requirements in China might be a consequence of residents’ life styles and the economic activities to support consumption demands in 2020. Under low-carbon life style scenario, per capita energy requirements of urban residents may decline to 97% in 2015 and 92% in 2020 in contrast with baseline scenario. That implies that China needs to pay a great attention to developing green low-carbon life style in order to realize mitigation target towards 2020.  相似文献   
40.
“地球工程”作为减缓气候变化手段的几个关键问题   总被引:1,自引:0,他引:1  
减缓气候变化可以在大的地理尺度上以工程技术手段来实施。地球工程包括所有能源生产和消费以外的、不涉及工业生产过程管理的,在较大的地球尺度或规模上,去除大气中的CO2或直接控制太阳辐射而降温的各种人为的工程技术手段,主要包括三大类:绿色生物技术手段、碳捕获与埋存技术和太阳光辐射额度控制管理技术。这一类地球工程手段有着一系列经济、技术、环境、伦理、安全和不确定性含义。本文就近年来国际上关于地球工程作为减缓气候变化可能技术选择的几个关键问题开展了分析和讨论,涉及概念界定、技术特点、可能影响、治理构架等。作者认为,对于直接作用于碳的地球工程手段,如绿色生物技术手段和碳捕获与埋存技术,风险小、可操控;太阳光辐管理技术,通过人为排放到大气的SO2和气溶胶等的降温效应,来控制地球气温的上升,尽管使用的经济成本可能不高,具有实际操作可能,但其巨大的不确定性和可能的安全含义,需要引起足够的重视。从伦理上看,当代人是否有权来开展太阳光辐管理技术这类具有巨大科学不确定性的地球工程存在争议,在科学不确定的情况下采取任何行动,就失去了伦理学基础。从法律上看,人工干预太阳辐射,即使是科学实验或研究,由于其影响超出了国界,超出了当代人,也超出了人类社会,如果有人采取行动,也存在法律依据上的质疑。人工干预太阳辐射的研究和实施,需要一个国际治理构架。为了防止其他国家单独行动,需要"相互约束"的治理构架——"自我约束"以换取他国同意"自我约束"。鉴于气候变化和光辐管理在科学上的不确定性,目前不宜实施,短期内也不会提上议事日程。太阳光辐管理技术影响的复杂性和气候变化风险的迫切性,需要我们加大科学研究力度,为科学决策提供依据。中国作为一个新兴经济体,世界第一大CO2排放国,地域空间气候条件存在巨大差异性。从减排成本的角度,从气候影响的空间差异性,开展地球工程的科学研究,有着科学、政策和国际气候外交的积极意义。但是,相关的科学研究需要国际制度构架。由于气候变化框架公约及其谈判尚未涉及,需要开展系统科学、技术、经济、法律和国家安全等方面的相关研究,提高科学认知度,为国际谈判和政策选择提供决策依据。  相似文献   
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