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481.
The Earth may be largely covered with water, but over one billion people are estimated to be without safe drinking water and almost 2.5 billion (40% of the world's population) without adequate sanitation at the outset of the new millennium. The provision of safe water and sanitation for all poses several serious institutional and economic challenges at international, national and local levels. Despite the various political commitments made from the late 1970s onwards, these commitments have remained largely unfulfilled. Even though some efforts to expand coverage have been made over the past two decades, much of those efforts have been undermined by socioeconomic problems and growing population, particularly in the urban areas of developing countries. The water supply and sanitation sector is actually in acute need of new investments for expansion and maintenance of facilities. Nonetheless, some positive trends can be discerned, such as, for example, the increasing recognition of integrated water resources management, environmental sanitation, public-private partnerships and women as a key for improvement and expansion of services. 相似文献
482.
充分利用水资源 改善生态环境 总被引:1,自引:0,他引:1
本文结合攀枝花地区实际,论述了水资源利用率高低是影响经济发展和改善生态环境的重要因素,调查分析了攀枝花地区水资源利用率低的原因;提出了提高水资源利用率的对策和措施。为促进经济发展和改善生态环境提供了依据。 相似文献
483.
通过多年的试验、示范证明,杂交稻具有旱能保产、湿能增产的特点,特别是在通气式大田水层栽插、湿润管理的条件下,具有节水、增产、改良土壤的作用。对在灌溉条件较差的丘陵山区和圩区发展水稻生产有积极的作用。 相似文献
484.
The article describes the historical development of water tariff policy in Tanzania from the colonial times to present. After
gaining independence, the country introduced “free” water policy in its rural areas. Criticism against this policy was expressed
already in the 1970s, but it was not until the late 1980s that change became unavoidable. All the while urban water tariffs
continued to decline in real terms. In rural and periurban areas of Tanzania consumers often have to pay substantial amounts
of money for water to resellers and vendors since the public utilities are unable to provide operative service. Besides, only
a part of the water bills are actually collected. Now that the free water supply policy has been officially abandoned, the
development of water tariffs and the institutions in general are a great challenge for the country. 相似文献
485.
Donald E. Evenson Joe C. Moseley 《Journal of the American Water Resources Association》1970,6(5):725-736
A set of simulation and optimization tools capable of analyzing the development and operation of a complex, multi-basin, interconnected water resource are explained. These models provide valuable information regarding the important questions: (1) “When should new projects be build?” (2) “How big should they be?” and (3) “How should the system be operated?” Since these tools were developed by and for practicing engineers, their applicability to real-world problems is mandatory. To assure this, testing was done on an actual proposed project, the Texas Water System. 相似文献
486.
Patrick Mann 《Journal of the American Water Resources Association》1973,9(5):976-984
ABSTRACT: The regulatory process such as that for water rates can be viewed as a bargaining process between regulators, utility management, and consumers. This bargaining process involves both political and economic influences. In an attempt to empirically verify that utility rates are a product of both economic and political factors, a sample of publicly-owned water utilities was subjected to regression analysis. As expected, cost and cost-related factors were positive and significant determinants of residential water rates. Using an admittedly imperfect measure of residential user political influence, there was evidence that increased political activity results in lower water rates. Furthermore, the political influence and water rate linkage is more evident in small water utilities than in larger suppliers. 相似文献
487.
无伤害事故由于没有造成伤害,往往被人们所忽视。事实上,事故的后果是具有随机性的,因此,在安全管理中,应重视对无伤害事故的管理,做好无伤害事故的收集、调查、分析、统计、处理和研究,从中找出事故规律,以采取防范措施,达到预防伤害事故发生的目的。 相似文献
488.
对于一个现有的除尘系统,若其除尘器、通风机的工作能力有足够的富余量,则可以在该系统管网上加接新的支管,来治理新的扬尘点。 相似文献
489.
虚拟现实技术在安全工程中的应用 总被引:23,自引:2,他引:21
论述了虚拟现实技术(VirtualReality)的基本原理、应用范围。结合大空间公用建筑火灾虚拟现实系统,提出了安全工程中应用虚拟现实技术的基本结构及程序设计关键技术,给出了大空间公用建筑火灾虚拟现实系统编制实例 相似文献
490.
ELLISON BA 《Environmental management》1999,23(4):429-439
/ This paper explores the new politics of western water policy through an examination of the Animas-La Plata water project and implementation of the Endangered Species Act. It is suggested that the focus of western water programming has shifted from the source of distributed funds, the United States Congress, to the agencies originally created to deliver federal benefits because funding for new project construction has not been forthcoming. Under this new system, members of Congress continue to excite their constituents with promises of money for new project starts, while the administrative agencies perform the myriad duties needed to keep these projects alive. The result is that political objectives have replaced operational/management objectives in administrative processes. In this case, the author demonstrates how resource managers in the Bureau of Reclamation manipulated hydrological analysis to control administrative process, why their manipulation was unfair, and perhaps illegal, and why biologists from the US Fish and Wildlife Service accepted the analysis. While ostensibly protecting all interests, the result is that none of the objectives of federal water programming are achieved. KEY WORDS: Environmental management; Administrative politics; Water policy; Endangered Species Act; Animas-La Plata, Bureau of Reclamation 相似文献