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981.
ABSTRACTWater shortages may present different and diverse implications for gender subgroups particularly in low-income settings. Yet, little research has documented the gendered livelihood implications of water shortages in Ghana. Based on a cross-sectional mixed method research involving a survey of 250 household heads and complemented with a qualitative study of 86 participants, the paper examines the differential effects of sporadic water supply in Tatale-Sanguli District of Northern Ghana. Our findings suggest that the livelihood effects of sporadic water supply in Tatale-Sanguli area are gendered, with females being disproportionately affected as compared to males. These differential effects are often framed by both gender role differentiation and inequities in access to vital productive resources and critical assets such as bicycles, tricycles and motor bikes. These findings highlight not only the need for local government and non-governmental organisations to step up efforts in water provision, but also to recognise the gendered effects of water shortages in Tatale-Sanguli District. Key to policy is also to ensure that programmatic interventions during water shortages take account of the likely gendered effects and differentiated burdens. 相似文献
982.
杨立静 《中国环境管理干部学院学报》2002,12(3):27-29
我国是世界上13个贫水国之一,水资源紧缺的问题在一些地区已制约经济和社会的发展。中水主要是指城市污水或生活污水经处理后达到一定的水质标准,可在一定的范围内重复使用的非饮用杂用水。中水的水质介于上水和下水之间,是水资源有效利用的一种形式。开展中水回收工作,已经显现出开源和减轻水污染的双重功能。 相似文献
983.
沱江内江段饮用水源的污染防治 总被引:6,自引:1,他引:5
通过加强对沱江内江段的水源污染进行防治,以及加快自来水厂制水工艺的改进,使集中式供水水质得到了明显改善,已取得较好的社会效益和环境效益 相似文献
984.
Ching-Pin Tung Douglas A. Haith 《Journal of the American Water Resources Association》1998,34(5):1071-1085
ABSTRACT: A set of simulation models consisting of a weather generator, and irrigation supply, soil moisture and crop growth components was used to evaluate the impacts of climate change on irrigated corn in locations near Albany, New York, Indianapolis, Indiana, and Oklahoma City, Oklahoma. The models evaluated the combined effects of modified water demand, supply and crop management (planting date, cultivar selection, irrigation). Simulations were duplicated for 100-year weather sequences based on current (1961–1988) weather statistics, and statistics modified by outputs from the GFDL GCM runs showing the effects from doubling of atmospheric CO2. Climate impacts differed greatly with location and management. Effects were most adverse in New York and least damaging in Indiana. At all sites, the beneficial effects of longer growing season and increased water supply were generally overcome by the detrimental impacts of increased evapotranspiration and reduced solar radiation during plant maturing stages. Adverse impacts of climate change can be substantially reduced by irrigation and appropriate selection of planting dates and cultivars. 相似文献
985.
B. J. C. Perera Gary P Codner 《Journal of the American Water Resources Association》1998,34(2):267-278
ABSTRACT: This paper describes two methods that are introduced to improve the computational effort of stochastic dynamic programming (SDP) as applicable to the operation of multiple urban water supply reservoir systems. The stochastic nature of streamflow is incorporated explicitly by considering it in the form of a multivariate probability distribution. The computationally efficient Gaussian Legendre quadrature method is employed to compute the conditional probabilities of streamflow, which accounts for the serial correlation of streamflow into each storage and the cross correlation between the streamflow into various storages. A realistic assumption of cross correlation of streamflow is introduced to eliminate the need to consider the streamflow combinations which are unlikely to occur in the SDP formulation. A “corridor” approach is devised to eliminate the need to consider the infeasible and/or inferior storage volume combinations in the preceding stage in computing the objective function in the recursive relation. These methods are verified in terms of computational efficiency and accuracy by using a hypothetical example of three interconnected urban water supply reservoirs. Therefore, it can be concluded that these methods allow SDP to be more attractive for deriving optimal operating rules for multiple urban water supply reservoir systems. 相似文献
986.
论河口海底淡水资源的形成 总被引:1,自引:0,他引:1
在分析沿海河口区域地质构造和层序地层学特征的基础上,提出了潜在的新的淡水资源---海底淡水资源,并研究了沿海河口区域海底淡水的形成、赋存、运移等特性。 相似文献
987.
论国家资源安全及其保障战略 总被引:30,自引:5,他引:30
论文系统探索了资源安全的基本内涵,并初步划分了不同类型国家资源安全。作者认为资源安全是资源供给与需求相互均衡的产物,它是一个内涵丰富的复合范畴。资源安全可以划分为全球性安全、区域性安全和地方性安全。按时间序列和资源生产与消费等,还可以将资源安全划分为短期资源安全、中期资源安全和长期资源安全,以及资源净出口国的资源安全和资源净进口国的资源安全。资源安全因其短缺或稀缺而来,并且首先表现为对石油安全的担忧。文章进一步分析了国家资源安全的涵义、基本特征、影响因素和发展趋势,分析了不同类型国家资源安全战略。最后,从系统分析的角度,提出了保障国家资源安全的七大基本策略,即资源保护战略、资源流通战略、资源消费战略、资源利用战略、资源回收战略、资源创新战略、资源管理战略,形成完整的国家资源安全复合保障体系。 相似文献
988.
989.
990.
One predicted impact of the construction of the hydroelectric plant of Brégnier-Cordon (Upper Rhône River, France) was the rise of the water table in the part of the plain situated upstream from the power plant. This impact made it possible to test the hypothesis that the slowing, indeed the halting, of ecological successions occurs in the former channels upstream from the power plant because of the increase of seepage supply through coarse alluvium. The vegetation of two braided former channels, one situated upstream (impacted site) and one downstream (reference site) of the power plant was studied over a period of nine years, before (1981) and after (1985, 1986, 1987, and 1989) the construction of the hydroelectric power-plant. The two sites had similar vegetation and successional stages at the beginning of the study. The seepage supply increases in the impacted site resulted in the establishment ofChara globularis andRiccia fluitans, indicating groundwater influence, but, after halting in 1985–1986, the ecological succession proceeded slowly again in 1987 and 1989, depicted by continuing eutrophication (expressed particularly by the increasing abundance ofCeratophyllum demersum). As expected, ecological succession was not halted in the reference site. Terrestrialization processes were apparent and changes were more rapid at its upstream part. 相似文献