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91.
Blasing T. J. Broniak Christine Marland Gregg 《Mitigation and Adaptation Strategies for Global Change》2005,10(4):659-674
Time series of fossil fuel carbon emissions from 1960–2000 for each of the U.S. states and the District of Columbia are presented
and discussed. Comparison of the nationally summarized results with other national datasets shows generally good agreement,
usually within 2%, and gives insight into the quality of all the data series. Our extension of the state-by-state emissions
estimates back to 1960 reveals patterns of change that are coherent across states and can be related to historic events such
as energy crises and federal legislation. Most notable is the changing pattern of coal usage, as coal-producing states produce
increasingly more energy (mostly for electricity) for other states so that per capita CO2 emissions diverge for states that import as opposed to those that export electricity. The decline in carbon emissions from
petroleum products following the 1970s is also evident. Per capita emissions range over an order of magnitude for the different
states. The data suggest that differences in per capita emissions arise from differences in many technological, physical,
resource, social, and economic factors. The data presented here and the few correlations briefly noted pose a challenge for
trying to use per capita emissions as a measure of equity or to provide mitigation targets. 相似文献
92.
厦门西港表层沉积物中有机氯化合物的污染特征及变化趋势 总被引:13,自引:3,他引:13
利用GC-ECD对厦门西港1998年7月取得的8个站位表层沉积物中的18种有机氯农药(HCHs,DDTs)等和12种多氯联苯(PCBs)进行分析。其中有机氯农药的浓度范围ND(未检测出)-0.58ng/g(其中HCHs和DDTs的含量分别为ND-0.14ng/gND-0.06ng/g),多氯联苯的浓度为ND-0.32ng/g,与1986、1993年的厦门西港的分析结果相比较,污染程度明显降低;说明近年来的厦门的有机污染得到逐步控制,也与有机物随时间推移逐渐详解有关,分析表明多氯联苯和有机氯农药在厦门西港有着相似的分布特征。 相似文献
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96.
“八五”至“十二五”期间,中国取得巨大的经济成果的同时带来了严重的水环境污染问题.文章分析了东中西部三大经济带经济发展及COD和氨氮两种主要水污染排放的差异,及其与经济发展的关系进行了EKC假说的实证研究.研究结果表明,部分污染物的拟合曲线尚处于上升阶段,未能出现典型的倒U型曲线,可能导致水环境质量恶化.环境基础设施建设、人口分布和产业结构等因素与COD和氨氮的排放量密切相关,因此,中国必须采取各种环境管理和技术手段,促使区域水污染物排放量指标与经济发展的拟合曲线出现转折点,改善水环境质量. 相似文献
97.
应用遥感技术,利用长时间序列的SPOT VEGETATION NDVI数据集,结合改进的像元二分模型,对豫西山区1998年、2003年和2008年的植被覆盖度进行计算。结果表明,豫西山区植被覆盖总体上略有上升,局部地区植被覆盖度有所下降。高海拔区域植被覆盖相对稳定,退化概率较低;低海拔区域植被退化和恢复的概率都相对较高;坡度小的区域植被退化和修复的概率都较高;坡度较大的区域植被轻微退化概率增大,坡度越大,植被覆盖修复的概率越低;南坡和北坡植被覆盖度相对较高,东坡和西坡植被覆盖度较低;西南坡向的植被退化相对严重,东南坡向植被退化概率相对较低。 相似文献
98.
Much quantitative research examining the determinants of the ecological footprint has been conducted cross-nationally, where data on cross-boundary flows have been readily available. While local-level studies of the footprint do exist for specific localities, most quantitative research at this scale has examined direct environmental impacts attributed to the internal activities of the locality, for instance, carbon emissions. Our analysis builds on this previous work by exploiting a local-level carbon footprint dataset with coverage for 28,321 zip codes across the United States. Following prior research, we focus on the effect of local affluence, measured in terms of median household income. In spatial regression models, we regress the per capita carbon footprint on local affluence, controlling for a variety of other factors. Consistent with previous work, we find that affluence is positively correlated the carbon footprint and there is no evidence of an environmental Kuznets curve. In the conclusion, we review the results of the study and discuss their implications for policy, specifically in terms of cross-boundary environmental problems. 相似文献
99.
Gasification is the thermochemical conversion of organic feedstocks mainly into combustible syngas (CO and H2) along with other constituents. It has been widely used to convert coal into gaseous energy carriers but only has been recently looked at as a process for producing energy from biomass. This study explores the potential of gasification for energy production and treatment of municipal solid waste (MSW). It relies on adapting the theory governing the chemistry and kinetics of the gasification process to the use of MSW as a feedstock to the process. It also relies on an equilibrium kinetics and thermodynamics solver tool (Gasify®) in the process of modeling gasification of MSW. The effect of process temperature variation on gasifying MSW was explored and the results were compared to incineration as an alternative to gasification of MSW. Also, the assessment was performed comparatively for gasification of MSW in the United Arab Emirates, USA, and Thailand, presenting a spectrum of socioeconomic settings with varying MSW compositions in order to explore the effect of MSW composition variance on the products of gasification. All in all, this study provides an insight into the potential of gasification for the treatment of MSW and as a waste to energy alternative to incineration. 相似文献
100.
陈小亮 《中国ISO14000认证》2014,(3):26-30
总结分析了中美两国二噁英有关标准的特点。我国二噁英相关的标准体系有待完善,主要集中在重点行业的烟气排放标准方面。美国二噁英相关标准体系较为完善,以风险评估为重点,二噁英排放源涉及的行业划分细致。排放标准分级明显,技术导向明显。通过对比分析指出,我国应继续深化重点行业的烟气排放控制的策略。加强二噁英风险评估的基础性研究工作,以减排技术为基础,强化分级管理的思路,并针对不同排放源细化二噁英的标准。 相似文献