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1.
法国巴黎地区曾面临有关水的三大挑战:塞纳河河水变化的控制、巴黎市民饮用水的供给和污水的排泄。这三大挑战目前已很好地得到了解决,巴黎地区的给排水系统已经修复好了,并制订和实施了一系列的水环境保护措施。本文总结巴黎地区给排水工程经验和水环境保护措施,并加以讨论。  相似文献   

2.
剖析了Taylor模式的要点或理论基础,认为否定环境对沉积物REE型式的影响,发现太古宙沉积物与元古宙沉积物REE型式的差异,提出太古宙末有全球性钾质花岗岩事件等,是Taylor模式的三个关键或紧密相连的三个主要环节。论证了Taylor模式的三大关键实属三大错误。然后探讨了Taylor模式的若干其它不足或所面临的问题。最后将错误和不足的原因归为Taylor错误地否定了环境对沉积物化学成分的影响,从而重新提出环境是影响沉积物微量元素配分的重要因素.不可忽视。  相似文献   

3.
《环境》2006,(2):55-55
我国未来能源供应面临三大挑战 党的十六大提出了全面建设小康社会和到2020年GDP产值比2000年翻两番的战略目标。按照这个目标进行我国未来的能源需求预测,结果表明到2010年一次能源需求总量将达到20.4亿吨标准煤,2020达到30.4亿吨标准煤。这样的预测结果要求在2001-2010年期间年均节能率必须达到2.2%,2010-2020年期间必须达到3%。  相似文献   

4.
环保信息     
中国生物多样性面临三大挑战21世纪中国生物多样性保护面临的挑战将来自3个方面,即生物技术与生物多样性保护,恢复生态学与生物多样性保护以及生物多样性与可持续发展.用生物方法治理巢湖向巢湖中大量投放能够摄食并消化蓝藻的滤食性鱼种黄鲢、白鲢,形成湖内鱼种优势互补,当年便有效地遏制了蓝藻的暴发.在净化巢湖水质的同时,渔民还可增产鲜鱼及增加收入. 摘自《中国环境报》环保信息  相似文献   

5.
建立中国绿色GDP核算体系:机遇、挑战与对策   总被引:5,自引:0,他引:5  
自1990年代提出“绿色GDP”概念到当前“绿色GDP”成为中国政府部门和研究机构关注热点,表明中国社会经济发展即将进入一个绿色GDP的时代。本文从国民经济核算的历史发展,分别论述建立中国绿色GDP核算面临的四大机遇,阐明了建立中国绿色GDP核算面临的观念、制度和技术三大挑战。针对这些机遇与挑战,提出了构建适合于中国国情的绿色GDP核算体系的五大对策。  相似文献   

6.
《中国资源报告》和《中国农业资源状况报告》编写工作简况人口、资源、环境已经成为全球性的三大问题,也是我国持续发展中面临的严峻挑战。人口问题的症结是资源的承载能力,环境问题的凸现是过度消耗资源并释放污染物。所以在缓解人类面临的三大问题的过程中,资源问题...  相似文献   

7.
有机食品是目前国际上对无污染天然食品比较统一的提法,通常来自于有机农业生产体系。在现代农业面临的生态平衡失调、资源能源危机、环境污染和食品品质下降等一系列挑战面前,有机农业及有机食品应运而生,并且发展迅速。欧盟、美国及日本三大市场1998年有机食品销售收入为130亿美元,2000年达到220亿美元,年平均增长率为25%~30%。预期本世纪初,有机食品的销售量将可达全世界食品销售总量的10%左右。欧盟已出台农业政策鼓励转换或保持有机种植,并给予农场主以相应的补贴。比如德国政府已确定了将有机农业种植…  相似文献   

8.
《环境》2009,(1):32-34
当世界上所有环保人士为巴拉克·奥巴马的胜利欢欣鼓舞时,人们似乎暂时忘了美国经济、环境和国家安全所面临的空前挑战。人们需要工作,也需要清洁的能源,同时还需要阻止全球变暖,而奥巴马,美国新当选的总统,向所有美国公民及世界承诺:“这是我上任后的头号目标。”然而,奥巴马的胜利能给地球“降温”吗?  相似文献   

9.
1.中国农业发展面临的严峻困难与挑战 1.1中国农业在自然资源、劳动、资本和科技教育上面临的困难挑战(见总第45期) 1.1.1中国基本国情决定农业在国民经济中具有特殊重要的地位(见总第45期) 1.1.2农业面临的严峻困难和增长粮食的艰难性(见总第45期) 1.2“成本高,效益低”是21世纪中国增产粮食的主要困难(见总第45期) 1.3中国目前粮食批发价格已高于国际市场价格(见总第46期) 1.4 21世纪上半期中国可能出现粮食产量缓慢增长的局面(见总第47期) 1.5莱斯特·布朗先生敲起的警钟:“谁…  相似文献   

10.
1.中国农业发展面临的严峻困难与挑战 1.1中国农业在自然资源、劳动、资本和科技教育上面临的困难与挑战(见总第45期) 1.1.1中国基本国增决定农业在国民经济中具有特殊重要的地位(见总第45期) 1.1.2农业面临的严峻困难和增长粮食的艰难性(见总第45期) 1.2“成本高,效益低”是21世纪中国增产粮食的主要困难(见总第45期) 1.3中国目前粮食批发价格已高于国际市场价格(见总第46期) 1.4 21世纪上半期中国可能出现粮食产量缓慢增长的局面(见总第47期) 1.5莱斯特·布朗先生激起的警钟:“…  相似文献   

11.
<正>"我们处在世界正在发生重大变革的时代,中国也正在实现着民族伟大复兴的关键时刻。青年人要承担什么责任?""我们应该团结更多的青年人,向全社会积极宣传环保理念,保护我们共同生存的家园。"一名青年使者刚刚回答完贾峰主任的问题,全场响起的是掌声——雷鸣般的掌声!8月17日,2015年"千名青年环境友好使者夏令营"在成都市温江区正式开营。环境保护部宣传教育中心主任贾峰亲临现场,并为青年学子们讲授了热情  相似文献   

12.
Types of asbestos are distinguished not only by structure, chemical compositon, shape of aggregates, and length and quality of fibers, but also by its formation. Though consisting of quite common elements, deposits are formed only under very special conditions. Its unique combination of properties has created over 3000 fields of application (about 70% in asbestos cement). Great efforts have been made to substitute all types of asbestos by harmless, similarly cheap and versatile synthetic fibers, owing to the unquestioned carcinogenic properties of all asbestos dusts. However, development of such fibers has not made any remarkable progress until recently. Consequently risk to workers in mining and manufactoring, consumers, outsiders, and the environment should be kept as low as possible by intensifying precautions and diminishing emissions.  相似文献   

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14.
This work was conducted to evaluate whether Ca-bearing additives used during coal combustion can also help with the retention of some other elements. This work was focused on the evaluation of bottom ashes collected during four full-scale combustion tests at an operating thermal fluidized-bed power station. Bottom ashes were preferred to fly ashes for the study to avoid interference from condensation processes usually occurring in the post-combustion zone. This work focused on the behaviors of S, Cl, Br, As, Mn, V, Cr, Ni, Cu,Zn, W, and Pb. Strong positive correlations with CaO content in bottom ashes were observed(for all four combustion tests) for S, As, Cl and Br(R = 0.917-0.999). Strong inverse proportionality was calculated between the contents of Pb, Zn, Ni, Cr and Mn and CaO, so these elements showed association to materials other than Ca-bearing compounds(e.g., to aluminosilicates, organic matter, etc.). Somewhat unclear behaviors were observed for W, Cu, and V. Their correlation coefficients were evaluated as statistically "not significant", i.e., these elements were not thought to be significantly associated with CaO. It was also discovered that major enrichment of CaO in the finest bottom ash fractions could be advantageously used for simple separation of elements strongly associated with these fractions, mainly S and As, but also Cl or Br. Removal of5% of the finest ash particles brings about a decrease in As concentration down to 77%-80% of its original bulk ash content, which can be conveniently used e.g., when high As content complicates further ash utilization.  相似文献   

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我们曾对从意大利收集的金枪鱼、箭鱼、普通鸬鹚以及家燕体内的p,p'-DDE、多氯联苯同类物(PCBs)、多氯二苯-p-二恶英(PCDDs)、多氯二苯并呋喃(PCDFs)以及多氯萘(PCNs)浓度进行过测量.  相似文献   

17.
In this paper, we present an overview of guidelinesdeveloped for the monitoring, evaluation, reporting,verification, and certification (MERVC) ofenergy-efficiency projects for climate changemitigation. The monitoring and evaluation ofenergy-efficiency projects is needed to determine moreaccurately their impact on greenhouse gas (GHG)emissions and other attributes, and to ensure that theglobal climate is protected and that countryobligations are met. Reporting, verification andcertification will be needed for addressing therequirements of the Kyoto Protocol. While the cost ofmonitoring and evaluation of energy-efficiencyprojects is expected to be about 5–10% of a project'sbudget, the actual cost of monitoring and evaluationwill vary depending on many factors, including thelevel of precision required for measuring energy andGHG reductions, type of project, and amount of fundingavailable.  相似文献   

18.
In order to say something substantial about the fundamental limits of machines (especially of computers) and of human calculations, we must explicate the concept of algorithm. Such an explication is provided by the Turing machine. Thus, problems have been discovered which cannot be solved algorithmically. For other problems there are problem-solving procedures, but no elegant algorithms. That men are fundamentally superior to machines has not been shown as yet.  相似文献   

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