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961.
上海市能源CO_2排放及节能减排的减碳效果分析   总被引:2,自引:2,他引:0  
以 2005 年为基准,采用 IPCC 清单指南推荐的方法测算了上海市能源活动产生的 CO2 排放清单。并采用情景分析方法,预测了高碳情景和低碳情景下上海市能源需求及相应的二氧化碳排放趋势,探讨了节能减排等低碳政策所产生的碳削减的潜力。研究表明,2005 年上海市能源活动所排放的 CO2 总量为 1.72 亿 t,其中,能源加工转换产生的 CO2 排放量为 7740 万 t,占排放总量的 44%;工业次之,占 30%;交通运输的排放比例为 16%。煤炭和石油的消费是导致 CO2 排放的主要原因,2005 年煤炭所带来的 CO2 排放量为1.10 亿 t,油品所产生的 CO2 排放量为 0.58 亿 t,分别占到能源活动 CO2 排放总量的 64.0%和 33.7%。 2005 年上海市人均 CO2 排放量为9.68 t/人,是世界平均水平的 2.4 倍,是中国平均水平的 3.8 倍。研究表明,在低碳政策下,上海能源需求将有所控制,到 2020 年全市能源需求总量为 1.6 亿 t 标煤, 比高碳情景节约 1.4 亿 t 标煤。节能减排政策还将使得全市能源活动 CO2 排放比高碳情景显著下降,到2020 年全市 CO2 排放量为 3.26 亿 t,比高碳情景减少 3.1 亿 t,低碳政策所产生的碳减排效益十分明显。  相似文献   
962.
In the last 40 years, a large area of savanna vegetation in Central Brazil (Cerrado) has been converted to agriculture, with intensive use of fertilizers, irrigation and management practices. Currently, the Cerrado is the main region for beef and grain production in Brazil. However, the consequences of these agricultural practices on NO, N2O and CO2 emissions from soil to atmosphere are still poorly investigated. The objectives of this study were to quantify soil emissions of NO-N, N2O-N and CO2-C in different no-till cultivation systems in comparison with native savanna vegetation. The agricultural areas included: (a) the maize and Brachiaria ruzizienses intercropping system followed by irrigated bean in rotation; (b) soybean followed by natural fallow; and (c) cotton planting over B. ruzizienses straw. The study was performed from August 2003 to October 2005 and fluxes were measured before and after planting, after fertilizations, during the growing season, before and after harvesting. NO-N fluxes in the soybean field were similar to those measured in the native vegetation. In the cornfield, higher NO-N fluxes were measured before planting than after planting and pulses were observed after broadcast fertilizations. During Brachiaria cultivation NO-N fluxes were lower than in native vegetation. In the irrigated area (bean cultivation), NO-N fluxes were also significantly higher after broadcast fertilizations. Most of the soil N2O-N fluxes measured under cultivated and native vegetation were very low (<0.6 ng N2O-N cm−2 h−1) except during bean cultivation when N2O-N fluxes increased after the first and second broadcast fertilization with irrigation and during nodule senescence in the soybean field. Soil respiration values from the soybean field were similar to those in native vegetation. The CO2-C fluxes during cultivation of maize and irrigated bean were twice as high as in the native vegetation. During bean cultivation with irrigation, an increase in CO2-C fluxes was observed after broadcast fertilization followed by a decrease after the harvest. Significantly lower soil C stocks (0-30 cm depth) were determined under no-tillage agricultural systems in comparison with the stocks under savanna vegetation. Fertilizer-induced emission factors of N oxides calculated from the data were lower than those indicated by the IPCC as default.  相似文献   
963.
半城市化地区已成为城市化研究的热点,但其生活垃圾管理问题常被忽视.以典型半城市化地区——厦门市集美区为例,通过问卷调查与实地采样两种方法,分析不同住区家庭生活垃圾产生的特征,并通过生命周期分析法,对比混合填埋、混合堆肥、混合焚烧以及分类处理4种垃圾处理方案的温室气体排放,提出相应的垃圾管理对策.结果表明:半城市化地区可...  相似文献   
964.
不同城市机动车尾气排放比较及数据可分享性评价   总被引:3,自引:2,他引:1  
宋宁  张凯山  李媛  陈琳 《环境科学学报》2011,31(12):2774-2784
针对我国绝大多数城市缺乏机动车相关基础数据的实际国情,探讨一种基础数据共享的可能性,用于城市机动车尾气排放清单的计算.以北京、上海、天津及成都4个城市为例,通过综合这些城市现有的机动车相关的基础数据(如机动车保有量,车龄分布,基于驾驶特征的发动机比功率(VSP),外界环境等),运用模型预测他们的机动车尾气排放并和相应城...  相似文献   
965.
加工制造业机械设备折旧过程CO2排放计量探讨   总被引:1,自引:0,他引:1  
利用折旧法中的楼梯法,再结合设备的主要组成物质的排放因子,初步分析了机械设备在折旧过程中排放的CO2量。研究表明,机械设备在折旧过程中排放的CO2量是碳排放计量工作中不可缺少的一部分。  相似文献   
966.
采用OECD专家组推荐的计算方法,在对比IPCC和国家气候变化协调小组(NCCG)第三工作组给出的碳排放系数后,在昆明市对外公布的2008年工业能耗统计数据基础上,对昆明市的工业碳排放进行了估算。还对昆明市的工业行业碳排放强度、昆明市工业碳排放的行业分布情况进行了初步分析。  相似文献   
967.
排污权交易制度是一种通过市场机制实现对环境容量资源的基础性配置,以达到控制污染、保护环境的方法。我国借鉴发达国家的成功经验,于1988年开始尝试引入排污权交易制度进行环境治理工作,并取得了一定的成效。但综合看来,我国排污权交易制度体系的构建仍处于起步阶段,在总量控制的科学确定、排污权初始的公平分配、培育交易市场等问题上仍有待于进一步探索和研究。  相似文献   
968.
根据联合国政府气候变化专门委员会(IPCC)2006年版碳排放指南中的计算公式和碳排放系数缺省值,计算了安徽省2000年-2009年能源消费和碳排放情况。结果表明:安徽省能源消费由2000年的4878.82万t标准煤增长到2009年的8895.90万t标准煤,平均年增长率为6.9%,其中第二产业部门能源消费量均占能源消费总量的79%以上;能源消费产生的二氧化碳由2000年的4107.48万t增长到2009年的8536.12万t,其中在各种能源消费碳排放量中原煤的碳排放量最大,占总碳排放量的77%82%;碳排放强度总体上呈现下降的趋势,低于全国平均碳排放强度,但高于全球和美国;碳排放的因素分析得出碳排放量与人口、人均GDP、能源强度呈现高度相关性。  相似文献   
969.
Executives are increasingly paying attention to the importance of supply chain management [Lambert DM, Cooper MC. Issues in supply chain management. Industrial Marketing Management 2000;29(1):65–83; Hagelaar GJLF, van der Vorst JGAJ. Environmental supply chain management: using life cycle assessment to structure supply chains. International Food and Agribusiness Management Review 2002;4:399–412]. The management of the supply chain can be a central aspect of a company's competitive advantage [Preuss L. Rhetoric and reality of corporate greening: a view from the supply chain management function. Business Strategy and the Environment 2005;14:123–139]. SCM also offers considerable opportunities to reduce a company's environmental impact. The supply chains of three small and medium enterprises (SMEs) operating in the Burnside Industrial Park in Nova Scotia, Canada were investigated to explore the opportunities to improve environmental performance of SMEs linked in supply chains. This study confirmed that time and, to a lesser degree, financial resources to address solid waste and energy issues are the greatest limiting factors. Small suppliers, and even to a certain degree medium-sized enterprises, have difficulties in allocating resources to initiatives that are not viewed as directly related to their core function, namely manufacturing the product or providing the service. This study clearly demonstrated that opportunities exist to reduce greenhouse gas emissions and solid waste. Although, the benefits that would be gained from the implementation of any of the individual actions in the supply chains explored in this study are individually small, the cumulative benefits that could be achieved among supply chains and within industrial parks are substantial, given the number of small- and medium-sized enterprises.  相似文献   
970.
In view of the increasing interest in the development and dissemination of technologies for harnessing new and renewable sources of energy in India, there have also been some efforts towards their use in the domestic lighting sector. However, the cumulative number of Solar Photovoltaic (SPV) lighting systems such as SPV lanterns and solar home lighting systems in India is far below their theoretical potential despite government subsidy programmes. One of the major barriers is the high capital investment in these systems. The Clean Development Mechanism (CDM) provides industrialized countries with an incentive to invest in emission reduction projects in developing countries to achieve a reduction in CO2 emissions at lowest cost that also promotes sustainable development in the host country. SPV lanterns and solar home lighting systems could be of interest under the CDM because they directly displace greenhouse gas emissions while contributing to sustainable rural development. However, only two SPV projects have been submitted under the CDM so far. This study assesses the maximum theoretical as well as the realistically achievable CDM potential of SPV lanterns and solar home lighting systems in India. The SPV lantern project is financially viable at a certified emissions reductions (CER) price of 34 € whereas the solar home lighting project is financially viable at a CER price of 46 €. While the maximum mitigation volume is about 35 million tonne CO2 on an annual basis, an estimate of achievable CER levels is done using the past diffusion trends of SPV systems. We find that annual CER volumes could reach 0.8 to 2.4 million by 2012 and 5.6 to 13.6 million by 2020. This would require that the government sets the subsidy level for SPV lighting systems at a level that allows them to become viable with the CER revenue. From a macro-economic point of view this makes sense if the sustainability benefits are deemed sufficiently high to warrant promotion of this type of project.
Axel MichaelowaEmail:
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