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271.
Philip M. Fearnside 《Mitigation and Adaptation Strategies for Global Change》2009,14(6):557-567
Amazonian forest reserves have significant carbon benefits, but the methodology used for accounting for these benefits will
be critical in determining whether the powerful economic force represented by mitigation efforts to slow global warming will
be applied to creating these reserves. Opportunities for reserve creation are quickly being lost as new areas are opened to
deforestation though highway construction and other developments. Leakage, or the effects that a reserve or other mitigation
project provokes outside of the project boundaries, is critical to a proper accounting of net carbon benefits. Protected areas
in the Amazon have particularly great potential mitigation benefits over an extended time horizon. Over a 100-year time frame,
virtually no unprotected forest is likely to remain, meaning that potential leakages (both leakage to the vicinity of the
reserves and that displaced by removing protected areas from the land-grabbing market) should not matter much because any
short-term leakage would be “recovered” eventually. The effect of the value attributed to time greatly influences the impact
of leakage on benefits credited to reserves. Simple assumptions regarding leakage scenarios illustrate the benefits of reserves
and the critical areas where agreement is necessary to make this option a practical component of mitigation efforts. The stakes
are too high to allow further delays in reaching agreement on these issues. 相似文献
272.
On the value of temporary carbon: a comment on Kirschbaum 总被引:1,自引:1,他引:0
Philip M. Fearnside 《Mitigation and Adaptation Strategies for Global Change》2008,13(3):207-210
A recent paper by Miko Kirschbaum (Mitigat Adapt Strategies Glob Change 11(5–6):1151–1164, 2006) argues that temporary carbon (C) storage has “virtually no climate-change mitigation value.” However, temporary carbon has
value in delaying global warming that needs to be recognized in carbon accounting methodologies. The conclusions reached are
very sensitive to any value that is attached to time. Basing analysis exclusively on the maximum temperature reached within
a 100-year time frame ignores other important impacts of global warming that also need to be included when mitigation strategies
are assessed. The relative weightings for long-term versus short-term impacts represent policy choices that result in a greater
or a lesser value being attributed to temporary carbon, but that value should not be zero. Global warming is too formidable
an enemy to allow us the luxury of discarding part of our arsenal in fighting against it. Both reducing fossil-fuel combustion
and increasing biosphere carbon stocks are needed. 相似文献
273.
首届"东北亚中亚区域可持续发展国际论坛"在北京召开。与会专家围绕着"全球气候变化背景下东北亚和中亚区域可持续发展"主题展开充分讨论,并形成重要研究结论。来自中国、俄罗斯、蒙古国、乌兹别克斯坦和以色列等国20多个研究机构的7位科学院院士、9位研究所所长和200多位专家学者讨论认为,面对积极应对全球变化的国际态势,加强东北亚中亚可持续发展国际合作研究具有重大战略意义,并向东北亚和中亚地区各国政府和专家学者发出共同倡议。此次国际论坛对加强东北亚和中亚地区在全球变化背景下资源生态环境与可持续发展科学问题与规律的国际合作研究具有重要推动作用。 相似文献
274.
275.
CO2 is the main greenhouse gas which causes global climatic changes on larger scale. Many techniques have been utilised to capture CO2. Membrane gas separation is a fast growing CO2 capture technique, particularly gas separation by composite membranes. The separation of CO2 by a membrane is not just a process to physically sieve out of CO2 through the controlled membrane pore size. It mainly depends upon diffusion and solubility of gases, particularly for composite dense membranes. The blended components in composite membranes have a high capability to adsorb CO2. The adsorption kinetics of the gases may directly affect diffusion and solubility. In this study, we have investigated the adsorption behaviour of CO2 in pure and composite membranes to explore the complete understanding of diffusion and solubility of CO2 through membranes. Pure cellulose acetate (CA) and cellulose acetate-titania nanoparticle (CA-TiO2) composite membranes were fabricated and characterised using SEM and FTIR analysis. The results indicated that the blended CA-TiO2 membrane adsorbed more quantity of CO2 gas as compared to pure CA membrane. The high CO2 adsorption capacity may enhance the diffusion and solubility of CO2 in the CA-TiO2 composite membrane, which results in a better CO2 separation. The experimental data was modelled by Pseudo first-order, pseudo second order and intra particle diffusion models. According to correlation factor R2, the Pseudo second order model was fitted well with experimental data. The intra particle diffusion model revealed that adsorption in dense membranes was not solely consisting of intra particle diffusion. 相似文献
276.
黄河流域生态系统脆弱、内部发展差异悬殊,探明黄河流域生态效率时空分异规律及其影响因素可为流域高质量发展提供重要保障。本研究基于黄河流域9省份2000—2018年经济、资源、环境相关的64个指标数据探索黄河流域生态效率,采用熵权法、全局SBM为基础的Global-Malmquist-Luenberger指数模型和变系数模型对生态效率时空变化趋势和影响动因开展实证研究。结果表明:① 2001—2018年,黄河流域整体生态效率虽有一定提升,但沿黄9省份平均水平均低于全国水平,且两极分化严重。随时间渐近,生态效率高值区(1.0以上)在流域下游聚集,生态效率低值区(0.2 ~ 0.6)向流域中部收缩。②时序影响分析发现,经济发展对生态效率正向驱动效果明显,科技创新的影响由正转负,环境治理和对外开放暂未发挥积极作用。③空间影响分析发现,上、中、下游存在显著的影响因素异质性。基于此,针对性地提出分区实施产业协同发展、优化环境治理投资、改善对外贸易结构、从全过程挖掘污染减排潜力等政策建议,为推动黄河流域经济发展与生态保护的均衡发展提供支撑。 相似文献