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951.
This paper presents a framework for understanding energy issues in the context of sustainable development. It posits that there are three important ways in which energy is related to sustainable development: (a) energy as a source of environmental stress, (b) energy as a principal motor of macroeconomic growth and (c) energy as a prerequisite for meeting basic human needs. These three dimensions correspond to the three dimensions of the often-used triangle of sustainable development: environmental, economic, and social. Using this framework, the paper traces how successive environmental summits at Stockholm (1972), Rio de Janeiro (1992) and Johannesburg (2002) have dealt with energy issues. It identifies a slow, surprising and important evolution of how energy issues have been treated at these global discussions. Energy has received increasing prominence at these meetings and become more firmly rooted in the framework of sustainable development. Stockholm was primarily concerned with the environmental dimension, Rio de Janeiro focused on both the environmental and economic dimensions, and the major headway made at Johannesburg was the meaningful addition of the social dimension and the linking of energy issues to the UN's Millennium Development Goals.  相似文献   
952.
Conflict caused by wild herbivores damaging crops is an almost universal problem in conservation. We designed and implemented a game-theory-based system for supporting farmers whose crops were being heavily damaged by wild herbivores. In this community-operated system, farmers self-report their production, which is endorsed by neighboring farmers. The average deficit in production is compensated for by a payment that is directly proportional to the average deficit in production of the group and to the individual farmer's productivity. As a result, farmers are compensated for the average damage (support) and rewarded for individual productivity (reward) (i.e., support cum reward [SuR]). The design of the game is such that only honest reporting gives maximum returns. Farmers who underreport receive less payment because the SuR amount is proportionate to their self-reported productivity. The endorsing farmers, in their own self-interest, prevent overreporting. The system involves multiple game situations, the combined result of which is a stable strategy based on honesty and hard work. In 2 villages along the western boundary of Tadoba Andhari Tiger Reserve in central India, we tested the system with 75 farmers over 6 crop seasons. After a few initial attempts to cheat, honesty prevailed throughout the group. Average crop productivity increased 2.5-fold, in spite of damage, owing to increased effort by farmers. Apart from wildlife conflict resolution, the model offers a promising alternative to crop insurance and a potential behavioral green revolution in agriculture.  相似文献   
953.
从高职学院人力资源开发与管理者的角度,通过对湖南工业职业技术学院师资队伍结构、素质和管理现状进行了SWOT分析,针对性地提出了高职学校师资队伍建设的战略思路、战略重点和系统策略.  相似文献   
954.
An understanding of the normal development of the urogenital tract, at both the structural and molecular level, gives an insight into the mechanisms involved in renal pathology. In this review we will outline embryology of normal and abnormal renal development and discuss the function of some of the key regulatory molecules which have been described recently. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
955.
Three collectives of substances - plastics, plant nutrients, biotoxins - are candidates for monitoring programmes that could keep track of the quality of ocean waters for vital life processes. All three are not subject to systematic surveillance at present. They are each characterized by long residence times in the marine environment, by increasing influx, and by growing evidence of their deleterious impacts on living systems.  相似文献   
956.
采用BCR(SM&T)方法对南四湖及主要入湖河流丰水季节表层沉积物中Cr、Cu、Mn、Ni、Pb、Zn 6种重金属元素的酸提取态、可还原态、可氧化态及残渣态进行了连续提取,分析了各水体单元表层沉积物重金属元素的形态组合特征、人为污染状况及潜在生态风险.研究结果表明,泗河、京杭运河、洙赵新河、府河上游、上级湖南部湖区及下级湖区表层沉积物中Cr、Cu、Ni、Zn以残渣态为主,其含量可占到该元素总量的80%~90%,人为污染程度较弱;老运河、府河入湖口、白马河表层沉积物中Cr、Cu、Ni、Zn的残渣态含量明显降低,而可提取态(酸提取态、可还原态、可氧化态)含量可增至80%以上,其中以可氧化态、酸提取态为主,人为污染程度较重;各水体单元表层沉积物中Pb、Mn以残渣态和可氧化态为主,其含量占Pb、Mn含量的95%、70%左右,基本未受人为污染.随着表层沉积物中有机物的矿化分解及环境条件的改变,老运河、府河入湖口、白马河等重金属人为污染较重的沉积物中Cr、Cu、Ni、Zn的可氧化态、酸提取态及可还原态可发生活化,具有较高的潜在生态风险.  相似文献   
957.
Zeolite synthesized from fly ash (ZFA) without modification is not efficient for the purification of NH4+ and phosphate at low concentrations that occur in real effluents, despite the high potential removal capacity. To develop an effective technique to enhance the removal efficiency of ammonium and phosphate at low concentrations, ZFA was modified with acid treatment and the simultaneous removal of ammonium and phosphate in a wide range of concentration was investigated. It was seen that when compared with untreated ZFA, only the treatment by 0.01 mol/L of H2SO4 significantly improved the removal efficiency of ammonium at low initial concentrations. The behavior was well explained by the pH effect. Treatment by more concentrated H2SO4 led to the deterioration of the ZFA structure and a decrease in the cation exchange capacity. Treatment by 0.01 mol/L H2SO4 improved the removal efficiency of phosphate by ZFA at all initial P concentrations, while the treatment by concentrated H2SO4 (≥0.9 mol/L) resulted in a limited maximum phosphate immobilization capacity (PIC). It was concluded that through a previous mild acid treatment (e.g. 0.01 mol/L of H2SO4), ZFA can be used in the simultaneous removal of NH4+ and P at low concentrations simulating real effluent.  相似文献   
958.
扎龙湿地南山湖沉积岩芯重金属污染特征及来源判别   总被引:4,自引:1,他引:3  
苏丹  臧淑英  叶华香  孙丽  贾晓丹  李苗 《环境科学》2012,33(6):1816-1822
选取扎龙湿地南部围湖造田、湖水养殖典型湖泊——南山湖为研究区,分析NSH2沉积岩芯中Hg、Cd、Pb、Cr、As、Mn、Ag、Cu、Co、Fe和Zn这11种重金属元素总量的垂向分布特征,结合颗粒组成指标,采用主成分分析的方法,并辅以210Pbex测年数据,研究了自1829年以来该湖区沉积物重金属元素污染特征、来源及污染历史.结果表明:①近两百年以来沉积物沉积速率经历了由慢到快再到慢的过程,沉积历史与南山湖流域人类的生产活动和水土保持政策相吻合;②1957年以前各元素含量变化趋势平稳,1957~1985年间存在小幅波动,1985年以后变化明显,其中Hg、Cd和Ag含量明显偏高;③NSH2沉积岩芯重金属污染来源以生活污水、化肥农药的流失以及煤与汽油等燃料的燃烧为主,其次是有机质降解、岩石风化和侵蚀,还存在工业排污源,贡献率分别为50.14%、19.90%和10.32%.南山湖重金属污染具有一定的潜在风险,在当地湖泊湿地污染治理中应予以足够的重视,此研究可为扎龙湿地湖区生态环境的整治与改善提供基础性的数据资料.  相似文献   
959.
基于人体健康风险的水污染事件污染物安全阈值研究   总被引:3,自引:1,他引:2  
水污染事件急性人体健康风险评估是环境科学的一个新兴研究领域.在简要介绍污染物急性风险评估方法的基础上,建立了水污染事件特征污染物安全阈值的计算模型.根据水污染事件特征污染物安全阈值计算方法,对我国2000~2010年间发生的主要水污染事件特征污染物的急性暴露安全阈值进行研究.结果表明不同水污染事件特征污染物的急性暴露安全阈值:氰化钠、镉、甲醛、氨氮、甲苯、硝基苯、微囊藻毒素-LR分别为0.1、0.6、8、20、6、0.07、0.004 mg.L-1.比较了急慢性安全阈值计算方法,其差异性在于污染物毒理学范围不同、饮用水暴露比例不同、暴露敏感人群不同.  相似文献   
960.
阐述了新形势对杭州市环保系统人才队伍建设提出的更高要求,系统分析了人才发展现状,从环保人才分类体系出发,提出了各类环保人才队伍建设的对策建议。  相似文献   
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