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421.
In recent years, China’s energy demand and Greenhouse gas (GHG) emissions have grown very fast, quite an amount of which was exported as energy embodied in goods in international trade rather than consumed domestically. Starting from the concept of embodied energy, based on input-output energy analysis approach, in this paper the energy embodied in goods in international trade of China during the period from 2001 to 2006 is calculated. The results show that although China has become a net importer of petroleum since 1993, China is a net exporter of embodied energy due to international trade in goods. In 2002, the total amount of energy embodied in exported goods was about 410 million tce (ton of coal equivalent, hereinafter referred to as "tce"). Eliminating the amount of energy embodied in imported goods of about 170 million tce, the net export of embodied energy was about 240 million tce, accounting for 16% of the aggregate primary energy consumption of that very year in China, and the net export of embodied emissions was about 150 million tons of carbon. With the rapid growth of China’s international trade, assuming no structural input-output changes of among sectors, in 2006 the net export of embodied energy went up to about 630 million tce, an increase of 162 % over 2002. In addition, this paper also analyzes the possible sources of error in calculation, and also discusses the policy implications according to the result of the calculation.  相似文献   
422.
Bolton M  Jeffrey A 《Disasters》2008,32(4):586-608
Following international interventions in Bosnia-Herzegovina(1) and Iraq, non-governmental organisations (NGOs) have played a central role in delivering humanitarian relief, encouraging participation in new systems of government, and advocating on behalf of marginalised groups. Although intervening agencies have framed such autonomous organisations as unquestionably virtuous, scholars have increasingly questioned the agency of NGOs, pointing to the constraining effects of funding and regulatory mechanisms. This paper contributes to this body of work by offering a detailed examination of legislation requiring NGOs to register with nascent state institutions. Drawing on case study material from Bosnia and Iraq, it argues that NGO registration should not be dismissed as a technical or legal matter, but that it should be embraced as a significant political practice embedded in relations of power. Registration legislation has increased the transparency of NGO funding origins and institutional practices, yet it has simultaneously acted as a barrier to smaller organisations and led to the transmission of international objectives through civil society entities.  相似文献   
423.
汶川大地震给中国造成了严重的损失,也再一次提醒国内外的决策者和研究人员必须注重发挥科学技术和国际合作在灾害防治和抗灾救助中的巨大作用。从当前国际减灾救援所面临的挑战出发,通过总结中国减灾国际合作的发展过程、发展现状以及在这次汶川大地震中减灾国际合作所发挥的作用,论述了在中国加强国际减灾合作的必要性及下一步的工作重点,以期为灾区的恢复重建和科学总结抗震救灾经验提供参考。  相似文献   
424.
淡水环境磷的生物有效性评估方法的发展动态   总被引:5,自引:0,他引:5  
磷在水体中含量较低,但在淡水生态系统中却是十分活跃的生源要素之一,其生物有效性往往是藻类水华的驱动力.本文对水环境中磷的生物有效性评估方法的发展现状进行了综述.目前发展了很多生物有效磷估算方法,但是没有完全认同的标准方法.从实验操作角度来看,藻类培养分析法最适于水样;化学提取法适于沉积物;而氧化铁材料等磷汇方法在水样及沉积物上均比较方便.事实上,生物有效磷概念含糊,是不可准确定量的.然而,为了更有效地评估磷的生物有效性,估算生物有效磷含量又是很有必要的.  相似文献   
425.
Environmental problems are often transboundary in nature. International cooperation to solve them has resulted in a growing number of environmental agreements. Supreme Audit Institutions, which are the highest national audit institutions in a country and are responsible for auditing the regularity of governmental expenditure and receipts, can contribute to the success of international cooperation by auditing government compliance with international environmental obligations and commitments. This is a new challenge for supreme audit institutions. To encourage and support this work a Workgroup on Environmental Auditing of the International Organisation of Supreme Audit Institutions has developed guidelines, which are presented in this article. The possible practical role of audit institutions is illustrated by the audit on the Convention on the Prevention of Marine Pollution by Ships, in which eight European audit institutions cooperated. This article is published in a personal capacity and does not necessarily reflect the views of the Netherlands Court of Audit.  相似文献   
426.
水环境中微囊藻毒素研究进展   总被引:58,自引:2,他引:58  
随着水体污染和富营养化进程的加剧,淡水水华暴发的频率和强度亦趋严重,笔者综述了有毒水华发生过程中释放的主要次级代谢物——微囊藻毒素的研究现状。该毒素是一类具有多种异构体的环状多肽物质。由于其毒性大、分布广、结构稳定,从而成为水环境中的潜在危害物质。对微囊藻毒素的产生、迁移及转化途径的研究已成为关注热点。微囊藻毒素作为安全性评价的风险因子,其分析方法主要有液相色谱和酶联免疫法等。为改善水源水质,逐步发展了包括物理、化学、生物等手段的控制方法。在总结国内外研究的基础上,根据我国实情,提出了微囊藻毒素在大型富营养化湖泊治理中的研究内容和方向。   相似文献   
427.
从2010年6月初至12月末,对厦门周边九龙江江东水库、厦门大学芙蓉湖和情人湖三个淡水湖库进行两周一次的连续采样,开展水体总碱性磷酸酶活性(APA)的研究。从营养盐和叶绿素a水平看,三个湖库属不同的富营养化程度:芙蓉湖>情人湖>江东水库。群落水平的总碱性磷酸酶活性和溶解性磷酸盐(SRP)浓度的结果表明,三处水体均呈现群落水平上的磷胁迫状态;不同水体的浮游植物群落结构存在显著差异,同时不同浮游植物的磷胁迫亦不同,蓝藻是芙蓉湖的绝对优势类群且标记率较低,绿藻是情人湖和江东水库的优势类群,且标记率较高。群落组成在一定程度上可以反映浮游植物群落的磷胁迫状态。  相似文献   
428.
基于知识图谱法的国际生态旅游研究分析   总被引:2,自引:0,他引:2  
论文采用“web of science TM核心合集”2005—2015年的面板数据,运用知识图谱法(CiteSpace)对国际生态旅游的研究文献进行实证分析,研究结果表明:1)国际生态旅游的研究规模逐渐扩大,且多集中在经济发达和生态资源丰富的地区。2)旅游、保护和管理是生态旅游研究的核心:“旅游”研究内容包括旅游资源、旅游活动影响和游客环境教育,“保护”研究内容包括生态资源保护和保护区研究,“管理”研究内容包括社区管理、管理指导原则和评价方法。3)学科发展经历了资源导向、社区经济和发展旅游三个阶段:资源导向阶段(2008—2010年),自然和文化资源是生态旅游目的地选址的重要条件;社区经济阶段(2010—2012年),广泛开始对社区生态旅游经济效益的分析;发展旅游阶段(2013—2014年),生态旅游市场研究、生态旅游者行为分析成为学科研究的又一重要方向。4)生态旅游活动的普及与地域性研究的深化、生态旅游市场化的研究和跨学科方法的运用将是未来生态旅游发展的三大趋势。  相似文献   
429.
甲萘威的淡水水生生物水质基准研究   总被引:2,自引:0,他引:2       下载免费PDF全文
为保护我国淡水水生生物,收集、筛选出5门23科44个物种的急性毒性数据和1门1科2个物种的慢性毒性数据,分别采用毒性百分数排序法和物种敏感度分布法,对我国甲萘威的淡水水生生物水质基准进行推导. 结果表明:我国淡水水生生物物种的急性毒性平均值范围为2.25~27 609 μg/L,甲壳纲急性毒性平均值范围为2.25~1 000 μg/L,鱼纲急性毒性平均值范围为700~27 609 μg/L,最敏感的物种为棘爪网纹溞,最不敏感的物种为胡鲶. 毒性百分数排序法推导出的基准最大浓度和基准连续浓度均为2.6 μg/L,物种敏感度分布法推导出的短期危险浓度和长期危险浓度分别为3.3和1.6 μg/L. 中美甲萘威的水质基准值差异归因于两国生物区系的不同. 甲壳纲对甲萘威的敏感度大于鱼纲. 初步统计表明,在22个天然水体样品中,有50%样品的甲萘威浓度高于淡水水质基准,存在环境风险.   相似文献   
430.
The rapid growth and intensification of freshwater fishery can cause imbalances between phosphorus (P) input in feed and its output in produce. This aquaculture can result in enriching exogenous P in fishponds and, consequently, accelerates the process of eutrophication. To assess relations among input, accumulation, release of P and as a consequence degrading water quality in terms of chlorophyll-a (Chl-a) in freshwater fishponds, fourteen fishponds with feed supply, nine fishponds without feed supply, and five nonfish ponds in Shaoxing Plain, southeast China were selected for comparing P accumulation in their waters and surface sediments. Surface sediment samples were collected from each pond to evaluate their total P, water soluble P, Olsen P, algal available P, and P fractions. Water samples were also collected from the ponds to measure concentrations of dissolved P and Chl-a. Total P in the sediments ranged from 0.88 to 1.73 g/kg in the fishponds with feed supply, that in the non-fish ponds ranged from 0.47 to 0.86 g/kg. Organic P, accounted for 23% to 60% of total P in the sediments, was an important P fraction and increased linearly with increasing organic matter. Long-term application of feeds resulted in increased P availability in the bottom sediments and degradation of water quality in the freshwater fishponds. Compared with non-fish ponds, sediments from the feed-supplied fishponds contained considerably higher Olsen P, algal available P, and water soluble P. Higher proportions of the labile P (NH4Cl-P) and potentially labile P (NaOH-IP) were also found in the sediments from the fishponds. High solubility of P in the sediments resulted in elevation of P and chlorophyll-a concentration in the pond water. The dissolved P concentration in the pond water increased in the order of non-fish ponds (12μg/L) 〈 fishponds without feed supply (24 μg/L) 〈 fishponds with feed supply (66 μg/L). Linear correlations between concentrations of total P, Olsen-P, algal available P, water-soluble P and P concentration in saturation extracts in the sediments and dissolved P in the pond water indicated that there was a buffering action of the sediment constituents on the dissolved P.  相似文献   
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