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181.
Lasco Rodel D. Pulhin Florencia B. 《Mitigation and Adaptation Strategies for Global Change》2000,5(1):81-97
Tropical forests in countries like thePhilippines are important sources and sinks of carbon(C). The paper analyzes the contribution of Philippineforests in climate change mitigation. Since the 1500s,deforestation of 20.9 M ha (106 ha) of Philippineforests contributed 3.7 Pg (1015 g) of C to theatmosphere of which 2.6 Pg were released this century. At present, forest land uses store 1091 Tg(1012 g) of C and sequester 30.5 Tg C/yr whilereleasing 11.4 Tg C/yr through deforestation andharvesting. In the year 2015, it is expected that thetotal C storage will decline by 8% (1005 Tg) andtotal rate of C sequestration will increase by 17%(35.5 Tg/yr). This trend is due to the decline innatural forest area accompanied by an increase intree plantation area. We have shown that uncertaintyin national C estimates still exists because they arereadily affected by the source of biomass and Cdensity data. Philippine forests can act as C sink by:conserving existing C sinks, expanding C stocks, andsubstituting wood products for fossil fuels. Here weanalyze the possible implications of the provisions ofthe Kyoto Protocol to Philippine forests. Finally, wepresent current research and development efforts ontropical forests and climate change in the Philippinesto improve assessments of their role in the nations Cbudgets. 相似文献
182.
Liquefied natural gas (LNG) is widely used to cost-effectively store and transport natural gas. However, a spill of LNG can create a vapor cloud, which can potentially cause fire and explosion. High expansion (HEX) foam is recommended by the NFPA 11 to mitigate the vapor hazard and control LNG pool fire. In this study, the parameters that affect HEX foam performance were examined using lab-scale testing of foam temperature profile and computational fluid dynamics (CFD) modeling of heat transfer in vapor channels. A heat transfer model using ANSYS Fluent® was developed to estimate the minimum HEX foam height that allows the vapors from LNG spillage to disperse rapidly. We also performed a sensitivity analysis on the effect of the vaporization rate, the diameter of the vapor channel, and the heat transfer coefficient on the required minimum height of the HEX foam. It can be observed that at least 1.2 m of HEX foam in height are needed to achieve risk mitigation in a typical situation. The simulation results can be used not only for understanding the heat transfer mechanisms when applying HEX foam but also for suggesting to the LNG facility operator how much HEX foam they need for effective risk mitigation under different conditions. 相似文献
183.
A critical analysis of earthquakes and urban planning in Turkey 总被引:2,自引:0,他引:2
The land use plans and policies of developed countries that live with the threat of earthquakes are gaining importance in reducing or eliminating the long‐term threat to people and property. In developing countries, however, these plans and policies seem to increase the level of vulnerability. This paper examines the effects of the earthquakes that have occurred in Turkey since 1992, with a particular focus on urbanisation and planning policies. It is based on extensive surveys carried out on location immediately after the earthquakes in Erzincan and Kocaeli‐Gölcük in 1992 and 1999, respectively. The analysis takes into account several factors, including the height of buildings, geological conditions and the construction period. The authors conclude that land use planning can serve as a very useful instrument for mitigating the extent of disaster damage if it is part of an appropriate planning system. In the case of Turkey, the planning system needs to be reorganised for this purpose. 相似文献
184.
中国水稻收获环节的损失有多高?——基于5省6地的实验调查 总被引:6,自引:0,他引:6
受资源禀赋的约束,减少粮食产后损失日益成为增加粮食供给、保障粮食安全的重要措施之一。论文采取实地测量的方法,在全国5省6地开展田间实验和调查访谈,考察了水稻收获环节的损失情况。结果显示:各实验地块水稻收获环节的损失率为1.18%~6.55%。其中,水稻联合收获的损失率显著高于分段收获,先进机型收获的损失率低于普通机型,田地湿度、倒伏程度与水稻收获环节的损失率正相关。结合水稻优势区域的分布推算,全国水稻收获环节的损失率为3.02%。减损的情景模拟表明,当全国水稻收获环节的损失率下降到2.76%(根据农业部《水稻机械化生产技术指导意见》测算),可节约稻谷54万t,可供439万人消费1 a,相当于节约耕地7.84万hm2,化肥2.61万t(折纯)。 相似文献
185.
SUSTAINABLE DEVELOPMENT AND HAZARDS MITIGATION IN THE UNITED STATES: DISASTERS BY DESIGN REVISITED 总被引:1,自引:0,他引:1
Dennis?S.?MiletiEmail author Julie?L.?Gailus 《Mitigation and Adaptation Strategies for Global Change》2005,10(3):491-504
It has become clear that natural and related technological hazards and disasters are not problems that can be solved in isolation.
The occurrence of disasters is a symptom of broader and more basic social problems. Since 1994, a team of over 100 expert
academics and practitioners – including members of the private sector – have assessed, evaluated, and summarized knowledge
about natural and technological hazards in the United States from the perspectives of the physical, natural, social, behavioral,
and engineering sciences. The major thesis of the findings was losses from hazards and inability to comprehensively reduce
losses of all types are the consequences of narrow and shortsighted development patterns, cultural premises, and attitudes
toward the natural environment, science, and technology. To address these broad and basic problems, the study included proposals
for ways in which people and the institutions of the United States can take responsibility for disaster losses, reduce future
hazard losses, and link hazard mitigation to sustainable development. 相似文献
186.
Active Amplification of the Terrestrial Albedo to Mitigate Climate Change: An Exploratory Study 总被引:1,自引:0,他引:1
Robert M. Hamwey 《Mitigation and Adaptation Strategies for Global Change》2007,12(4):419-439
To date, international efforts to mitigate climate change have focussed on reducing emissions of greenhouse gases in the energy,
transportation and agriculture sectors, and on sequestering atmospheric carbon dioxide in forests. Here, the potential to
complement these efforts by actions to enhance the reflectance of solar insolation by the human settlement and grassland components
of the Earth's terrestrial surface is explored. Preliminary estimates derived using a static two dimensional radiative transfer
model indicate that such efforts could amplify the overall planetary albedo enough to offset the current global annual average
level of radiative forcing caused by anthropogenic greenhouse gases by as much as 30% or 0.76 Wm− 2. Terrestrial albedo amplification may thus extend, by about 25 years, the time available to advance the development and use
of low-emission energy conversion technologies which ultimately remain essential to mitigate long-term climate change. While
a scoping analysis indicates the technical feasibility of sufficiently enhancing human settlement and grassland albedos to
levels needed to achieve reductions in radiative forcing projected here, additional study is required on two fronts. Firstly,
the modelled radiative forcing reductions are static estimates. As they would generate climate feedbacks, more detailed dynamic
climate modelling would be needed to confirm the stationary value of the radiative forcing reduction that would result from
land surface albedo amplification. Secondly, land surface albedo amplification schemes may have important economic and environmental
impacts. Accurate ex ante impact assessments would be required to validate global implementation of related measures as a viable mitigation strategy. 相似文献
187.
Msangi JP 《Environmental monitoring and assessment》2004,99(1-3):75-87
Droughts have been occurring persistently in southern African dryland regions for over a century. The impacts of droughts
on people, their domesticated animals, wildlife, rangelands and cropped lands have been shown to be astronomical. If left
alone the rangelands often recover after the calamity, however human occupation has led to irreversible damage. Even though
some communities have evolved viable and sustainable coping mechanisms, recent times have seen weakened coping strategies
leading to loss of life in most of the 10 countries in southern Africa. While land degradation has many inter-related causes
and effects, drought-related effects have proven most difficult to manage and/or overcome. Drought-related land degradation
or desertification poses a huge threat to sustainable land and resource management in the region. The paper examines appropriate
drought mitigating initiatives, linking them to land tenure and land management practices. Numerous interventions targeted
at reducing poverty and improvement in resource management have failed to achieve desired effects due to rigidity and imposition,
and failure of the external interveners to recognise and incorporate indigenous peoples’ preferences and coping strategies.
Non-governmental organisations and authorities’ willingness to institute drought and desertification combating measures are
reviewed, highlighting the role that community action plays in reducing adverse effects in the region. Linkages to trade patterns
that perpetuate poverty and unwise use of resources are discussed. Adopting ‘people centred’ mitigating measures is emphasised.
Success rests with both the people in the ‘south’ and those in the ‘north’. What is required is an informed global action. 相似文献
188.
工业园区由于资源能源消耗和污染排放总量大,能量梯级利用水平普遍较低,在我国推进生态文明建设的过程中受到了重点关注.本研究以河南省一个典型的高能耗工业园区(永城经济技术开发区)为研究对象,对能量梯级利用措施带来的节能效果和大气污染物减排效益进行了定量的研究,并且结合CALPUFF模型分析园区能量梯级利用措施对周边城市大气环境质量的影响.结果表明:①通过应用能量梯级利用措施,有效地提高了能源的使用效率,并减少了SO2、NOx以及颗粒物等主要大气污染物的排放量.园区12条能量梯级利用链条的节能总量为10000 TJ, SO2和NOx排放量分别减少为611 t和1407 t, PM10 和PM2.5分别减少为82 t和45 t.②CALPUFF模拟结果显示园区采用能量梯级利用措施在一定程度上改善了城市大气环境的空气质量.永城市2017年4种污染物的最大1 h平均浓度在有能量梯级利用措施情景(S2)下和无能量梯级利用情景(S1)相比均有所降低,其中NOx降幅最为明显,在春秋两季为70 μg·m-3左右. 相似文献
189.
Mandeep Sekhon 《International Journal of Green Energy》2019,16(2):167-184
A novel design of twin-chamber community solar (TCCS) cooker is presented as a replacement of biomass-based cooking. The novelty of separating a single rectangular cooking chamber into separate twin chambers (of 1-m2 aperture area each) improves the cooking performance as opening of one chamber for unloading of food cooked in lesser time (rice) does not disturb the stagnation temperature of the other chamber (pulses and meat) needing more time to cook besides resulting in reduction in side heat loss coefficient due to common wall. Aperture area and cooking volume of TCCS cooker are 9.54 and 35.33 times more as compared to single-chamber domestic solar (SCDS) cooker which makes it a community-scale large-capacity solar cooker. The developed solar radiation capture model and overall heat loss coefficient (Ul) computed for TCCS cooker have been used in a thermal model developed between various interactive components. First (F1) and second figures of merit (F2) values are 0.13 and 0.42, respectively, for TCCS cooker at par with ‘A’ grade category SCDS cooker. Techno-economic analysis shows that the net present value of TCCS cooker is Rs. 83,253 with break-even point occurring after cooking 43,461 meals with payback period of only 25, 50, and 72 months if used as a replacement for LPG, cow dung cakes, and wood-based cooking, respectively. Environmental impact analysis shows that the use of the proposed cooker can mitigate 2, 5.9, and 4.1 tonnes of CO2 emissions every year by not burning LPG, cow dung cakes, and wood respectively. 相似文献
190.
为了探究易燃易爆场所静电事故形成过程及防护机理,基于事故链式理论,以及静电点燃源形成过程和爆炸性环境形成过程这2条并行支链,绘制了易燃易爆场所静电事故链路;通过事故案例说明了静电事故链路的实用性;研究了静电荷、易燃/可燃物质在外界扰动作用下的特征形态。研究结果表明:静电事故断链减灾模式包括静电点燃源断链减灾模式、爆炸性环境断链减灾模式以及降低事故影响的事故后果断链减灾模式;针对静电事故的各类断链减灾模式,提出了相应的防护措施,可为易燃易爆场所静电事故防护提供系统性的指导方案。 相似文献