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961.
The European Union (EU) is an important destination for developing country exports. Has the EU’s commitment to the Kyoto Protocol induced developing countries to reduce their carbon dioxide (CO2) emissions? Our analyses of 136 developing countries from 1981 through 2007 suggests that: developing countries’ export dependence on the EU is associated with CO2 emission reductions post-Kyoto in relation to the pre-Kyoto time period; this also holds for SO2, which, while not covered under Kyoto, is linked with CO2 emission levels; this does not hold for PM10, a pollutant which is not covered under Kyoto and is not directly associated with CO2 emissions related to industrial activities; developing countries’ export dependence on non-EU developed countries and on the rest of the world is not associated with significant reductions in emissions between pre- and post-Kyoto for these pollutants . In sum, even in the absence of binding regulatory mandates, the EU appears to exert market leverage to project its regulatory preferences abroad. 相似文献
962.
963.
Responses of CH(4), CO(2) and N(2)O fluxes to increasing nitrogen deposition in alpine grassland of the Tianshan Mountains 总被引:2,自引:0,他引:2
To assess the effects of nitrogen (N) deposition on greenhouse gas (GHG) fluxes in alpine grassland of the Tianshan Mountains in central Asia, CH4, CO2 and N2O fluxes were measured from June 2010 to May 2011. Nitrogen deposition tended to significantly increase CH4 uptake, CO2 and N2O emissions at sites receiving N addition compared with those at site without N addition during the growing season, but no significant differences were found for all sites outside the growing season. Air temperature, soil temperature and water content were the important factors that influence CO2 and N2O emissions at year-round scale, indicating that increased temperature and precipitation in the future will exert greater impacts on CO2 and N2O emissions in the alpine grassland. In addition, plant coverage in July was also positively correlated with CO2 and N2O emissions under elevated N deposition rates. The present study will deepen our understanding of N deposition impacts on GHG balance in the alpine grassland ecosystem, and help us assess the global N effects, parameterize Earth System models and inform decision makers. 相似文献
964.
965.
966.
低碳经济:中国实现绿色发展的根本途径 总被引:11,自引:0,他引:11
应对全球气候变化,保障能源安全是世界各国共同面对的挑战。中国作为一个新兴的发展中大国,不仅人口众多,经济发展、消除贫困、保障民生的任务极为繁重,人均GDP需要保持持续增长,而且能源消费以煤炭为主,CO2排放量居世界第二,同时煤炭资源禀赋较差,其温室气体排放的强度和控制的难度比较大,再加上我国能源技术相对较为落后,实施技术改造和产业转型升级的难度也比较大,我国减排的压力不容小视。中国要从根本上降低CO2排放量,实现节能减排,促进绿色发展,必须找出实现节能减排,促进绿色发展的关键环节,其途径在于大力发展低碳经济,发展包括低碳经济在内的循环经济和节能经济、清洁生产、生态经济以及绿色消费,促进绿色发展。针对低碳经济的理论基础、发展的国际背景,以及我国发展低碳经济的优势、机遇和挑战等问题,本文进行了深入分析,并提出了我国发展低碳经济的具体措施建议。 相似文献
967.
张小刚 《中国人口.资源与环境》2011,(Z1)
低碳经济包含三个核心要素,即发展目标、减排和成本。发展低碳经济就是要在这三者之间达成一种平衡,也就是在保证发展目标的前提下,实现低排放和低成本。如果单纯为了经济快速转型和兑现减排承诺,而制定和实施强制减排政策,必然引发各种经济冲突和社会矛盾,从而使低碳经济发展陷入困境。从根本上讲,应该把低碳经济纳入国家整体发展规划进行考量,而不仅仅是作为工业减排的附属品。 相似文献
968.
Atmospheric radioactivity is monitored for the verification of the Comprehensive Nuclear-Test-Ban Treaty, with xenon isotopes 131mXe, 133Xe, 133mXe and 135Xe serving as important indicators of nuclear explosions. The treaty-relevant interpretation of atmospheric concentrations of radioxenon is enhanced by quantifying radioxenon emissions released from civilian facilities. This paper presents the first global radioxenon emission inventory for nuclear power plants, based on North American and European emission reports for the years 1995–2005. Estimations were made for all power plant sites for which emission data were unavailable. According to this inventory, a total of 1.3 PBq of radioxenon isotopes are released by nuclear power plants as continuous or pulsed emissions in a generic year. 相似文献
969.
John S. Kinsey Peter H. Kariher Yuanji Dong 《Atmospheric environment (Oxford, England : 1994)》2009,43(32):4959-4967
The fine particle emissions from a U. S. certified non-catalytic wood stove and a zero-clearance fireplace burning Quercus rubra L. (northern red oak) and Pseudotsuga menziesii (Douglas fir) cordwood each at two different moisture levels were determined. Emission testing was performed using both time-integrated and continuous instrumentation for total particle mass, particle number, particle size distribution, and fixed combustion gases using an atmospheric wind tunnel, full-flow laboratory dilution tunnel, and dilution stack sampler with a comparison made between the three dilution systems and two sampling filter types. The total mass emission factors (EFs) for all dilution systems and filter media are extremely variable ranging from <1 to 55 g kg−1 of dry wood depending on the combination of appliance type, wood species and moisture content, filter medium, and dilution system. For Teflon filter sampling of stove emissions in the wind tunnel, the total mass EFs varied from 2 to 8 g kg−1 of dry fuel depending on wood type whereas the equivalent fireplace emissions burning wet oak averaged 11 g kg−1. A substantial number of ultrafine particles in the accumulation size range were also observed during all tests as determined by an Electrical Low Pressure Impactor (ELPI) and Scanning Mobility Particle Sizer. The PM-2.5 (particles ≤2.5 μm in aerodynamic diameter) fractions determined from the ELPI electrometer data ranged from 93 to 98% (mass) depending on appliance type as reported previously by Hays et al. (Aerosol Science, 34, 1061, 2003). 相似文献
970.
P. Saide R. Zah M. Osses M. Osss de Eicker 《Atmospheric environment (Oxford, England : 1994)》2009,43(32):4914-4923
Simple, inexpensive and accurate methods for assessing the spatial distribution of traffic emissions are badly needed for the environmental management in South American cities. In this study, various spatial disaggregation methods of traffic emissions of carbon monoxide are presented and evaluated for a large city (Santiago de Chile). Previous methods have used a simplified road network as a proxy for deriving spatial patterns of emissions. However, these approaches resulted in underestimation of emissions in urban centers, industrial zones and highly loaded roads, as well as overestimation in residential zones. Here we modify these methods by adding data correlated with the emissions (e.g. traffic counts, vehicles mean speed, road capacity) solving partially or completely the indicated problems. After an accuracy-simplicity analysis two methodologies stand out over the others: using traffic count classification and using a land use map, both combined with a simplified road network. Both are top–down approaches that correlate well (0.9) with the reference emissions and capture emission peaks (within 30% relative error). Hence the proposed changes allow an improved balance between accuracy and costs (monetary, availability of data and time to obtain data). 相似文献