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141.
特大型城市客运交通碳排放与减排对策研究   总被引:2,自引:0,他引:2  
本文基于对现有城市交通碳排放测算方法的比较分析,以上海市为例,采用IPCC"自下而上"法对特大型城市客运交通CO2排放进行了测算,结果显示:轨道交通是碳排放效率最高的客运方式,出租车最低;客运交通CO2排放总量增长迅速,且碳源结构发生了较大变化;近年客运交通CO2排放增量主要来自私人载客汽车,同时公务交通在客运交通碳排放中始终占较大比重。由此本文认为,控制客运交通碳排放的关键在于对以私人载客汽车和单位载客汽车为主的个体交通的管理和控制,形成以公共交通为主的交通结构。在此基础上,为了将控制碳排放纳入到城市交通政策目标中去,本文就主要城市交通政策对客运交通碳排放产生的影响进行了深入分析,并得出结论:以往的交通供给、需求管理政策对于抑制客运交通碳排放增长的作用有限;而就目前城市空间发展政策的实施效果而言,也不利于降低居民出行的碳排放水平。文章最后分别从交通供给、需求管理以及城市空间角度给出了控制客运交通碳排放的对策。  相似文献   
142.
土壤-植物系统中磷和砷相互作用关系的研究进展   总被引:2,自引:0,他引:2  
陈静  方萍 《四川环境》2010,29(6):118-121
砷元素导致的环境污染问题日益突出,施磷已成为植物修复砷污染土壤过程中必要强化措施之一。土壤-植物系统中磷和砷的相互作用关系是非常复杂的,研究表明:磷和砷在土壤中往往是共生的,但又存在竞争吸附关系;磷和砷在不同植物中的相互作用关系主要有拮抗效应和协同效应;有必要通过分子生物学手段对磷和砷表达基理进行深入研究,获得对砷具有超积累能力的植株。  相似文献   
143.
Policies such as the US Healthy Forests Restoration Act (HFRA) mandate collaboration in planning to create benefits such as social learning and shared understanding among partners. However, some question the ability of top-down policy to foster successful local collaboration. Through in-depth interviews and document analysis, this paper investigates social learning and transformative learning in three case studies of Community Wildfire Protection Planning (CWPP), a policy-mandated collaboration under HFRA. Not all CWPP groups engaged in social learning. Those that did learned most about organisational priorities and values through communicative learning. Few participants gained new skills or knowledge through instrumental learning. CWPP groups had to commit to learning, but the design of the collaborative-mandate influenced the type of learning that was most likely to occur. This research suggests a potential role for top-down policy in setting the structural context for learning at the local level, but also confirms the importance of collaborative context and process in fostering social learning.  相似文献   
144.
Drawing on Ajzen's Theory of Planned Behaviour, this paper analyses whether there is a relation between management's behavioural intentions toward an environmental problem and the company's specific actions in this area, and also considers the impact of the company size on these actions. For the data, a questionnaire was sent to 184 managers employed in industrial companies located in Spain which belonged to the automobile industry. The empirical analysis produces positive and significant regression coefficients and provides support for the hypotheses proposed. Specifically, the results show that the environmental actions carried out in the company respond at least in part to management's behavioural intentions toward these issues and the size of the firm.  相似文献   
145.
土地政策参与宏观调控是在特定经济背景下提出的.随着时间的推移和经济环境的变化,土地政策在h参与宏观调控的过程中也应做出相应的调整.列举了新经济背景下土地调控手段存在主次错位、刚性不强、缺乏有效配合等一系列问题,针对这些问题提出了在土地政策参与宏观调控的过程中要增加地土经济手段的运用、推动土地政策法律化和增强部门间协调配合等相关对策与建议.  相似文献   
146.
分析了2009年9月26日美国对中国轮胎进口实施的特别保护措施,运用国际贸易和国际经济学的相关理论,对美国轮胎特保法案进行了剖析。在目前中美轮胎贸易情况下,从宏观和微观的角度探讨了轮胎贸易顺差形成的原因,以及长期和短期内对中国经济的影响,并对中国轮胎出口贸易提出了几点政策建议。  相似文献   
147.
The Fallacies of Concurrent Climate Policy Efforts   总被引:1,自引:0,他引:1  
Marian Radetzki 《Ambio》2010,39(3):211-222
Climate policy has assumed an extreme degree of urgency in the international debate in recent years. This article begins by taking a critical look at the scientific underpinnings of the efforts to stabilize the climate. It points to several serious question marks on the purported relationship between greenhouse gas emissions and global warming, and expresses distrust about claims of impending catastrophes related to rising sea levels, hurricanes, and spread of infectious disease. It then reviews the concurrent climate policy efforts and concludes that they are incoherent, misguided and unduly costly, and that they have so far had no perceptible impact on anthropogenic greenhouse gas emissions. The exceedingly ambitious policy plans currently under preparation suffer from similar fallacies. For these reasons, but also because of the remaining scientific doubts and the exorbitant costs that have to be incurred, skepticism is expressed about the preparedness to implement the climate policy plans currently on the table.  相似文献   
148.
Carbon dioxide emissions have accelerated since the signing of the Kyoto Protocol. This discouraging development may partly be blamed on accelerating world growth and on lags in policy instruments. However, it also raises serious question concerning whether policies to reduce CO2 emissions are as effective as generally assumed. In recent years, a considerable number of studies have identified various feedback mechanisms of climate policies that often erode, and occasionally reinforce, their effectiveness. These studies generally focus on a few feedback mechanisms at a time, without capturing the entire effect. Partial accounting of policy feedbacks is common in many climate scenarios. The IPCC, for example, only accounts for direct leakage and rebound effects. This article attempts to map the aggregate effects of different types of climate policy feedback mechanisms in a cohesive framework. Controlling feedback effects is essential if the policy measures are to make any difference on a global level. A general conclusion is that aggregate policy feedback mechanisms tend to make current climate policies much less effective than is generally assumed. In fact, various policy measures involve a definite risk of ‘backfiring’ and actually increasing CO2 emissions. This risk is particularly pronounced once effects of climate policies on the pace of innovation in climate technology are considered. To stand any chance of controlling carbon emissions, it is imperative that feedback mechanisms are integrated into emission scenarios, targets for emission reduction and implementation of climate policy. In many cases, this will reduce the scope for subsidies to renewable energy sources, but increase the scope for other measures such as schemes to return carbon dioxide to the ground and to mitigate emissions of greenhouse gases from wetlands and oceans. A framework that incorporates policy feedback effects necessitates rethinking the design of the national and regional emission targets. This leads us to a new way of formulating emission targets that include feedback effects, the global impact target. Once the full climate policy feedback mechanisms are accounted for, there are probably only three main routes in climate policy that stand a chance of mitigating global warming: (a) returning carbon to the ground, (b) technological leaps in zero-emission energy technology that make it profitable to leave much carbon in the ground even in Annex II countries and (c) international agreements that make it more profitable to leave carbon in the ground or in forests.  相似文献   
149.
我国脱硝市场任务艰巨,政策扶持将催生爆发性机遇。脱硝产业目前存在缺乏具有自主知识产权的核心技术、绝大多数单位依靠引进技术、市场竞争处于无序状态等问题;提出了发展脱硝市场的应对措施,建议建立市场准入制度和经济补贴政策,加强排放标准制订工作。  相似文献   
150.
低碳生活是一种自然地节约各种资源的习惯,是一种生活习惯。气候变化是本世纪最严重的全球问题之一,不断推进低碳生活是减少人类生活对气候影响的重要途径。低碳生活推广后,消费者对建筑的规划、环境影响以及节能等关注将增加,进而影响建筑行业的发展。在分析低碳生活对建筑影响的基础上,提出了包括人才培养、政策支持和扩大宣传的多级支持发展建议。  相似文献   
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