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1.
ABSTRACT

This article addresses the problem of identifying annual operation, maintenance, and replacement (OM&;R) expenditures needed to maintain performance of the water delivery system in Egypt. The deliver system, which includes the High Aswan Dam (HAD), large irrigation structures. pump stations, ond thousands of canals and drains, is described. Procedures for estimating these OM&;R costs and assessing system benefits in the various use sectors are presented. The article also explains the development and application of a cost allocation model to estimate the share of the various use sectors from the system cost.  相似文献   

2.
Abstract

Because of political risk, economic feasibility, and cultural concerns, it has been a great challenge for economists to provide palatable remedies to governments to promote water allocation efficiency. Considering the limitation of water pricing to irrigation water, this research addresses questions of which strategic policy alternatives to water pricing might improve irrigation water allocation efficiency. An empirical framework is provided to compare irrigation policies for allocating scarce water to agricultural production in Egypt and Morocco. Partial-equilibrium agricultural sector models specific to Egypt and Morocco were employed for policy tests. Consumer and producer surplus from agricultural based commodities is maximized subject to various resources, technical, and policy constraints. Positive Mathematical Programming (PMP) was used to calibrate the model. Water pricing policy, water complementary input factor tax policy, and output tax policy are tested using these two agricultural sector models. Results suggest that effective policy depends on the social, economic, and environmental contexts of specific regions. For countries like Egypt where most agricultural land is irrigated, taxes on Nitrogen (N) fertilizer and energy and output tax on water-intensive and low profit crop production may be more effective than others. For the Moroccan case, taxation on crop inputs and outputs not only affect water use in the public irrigation sector, but also private irrigation sector and rain-fed as a whole. Water pricing and output tax policies are better suited and effective than water complementary input factor taxation. Findings from Morocco might be generalized to other countries with similar irrigation characteristics and diversity in irrigated (public and private) and rain-fed land. The results for both countries demonstrate that some of the strategic irrigation policies can work towards directing cropping decisions to less water intensive crops and also generating revenues for governments in situations where governments choose not to price water.  相似文献   

3.
灌区多目标供水优化调度模型及其求解   总被引:4,自引:0,他引:4  
黄牧涛  王乘 《水力发电》2003,29(7):16-19
针对灌区水资源供需矛盾十分突出的问题,以云南曲靖灌区为研究对象,应用大系统分解协调原理,建立了两层递阶水资源优化调度模型,并采用模拟技术与优化技术相结合的途径,进行优化模型的求解,给出了优化决策算法的程序框图,合理解决了多水源、多目标、多用户、多保证率的供水调度问题。研究结果可为同类灌区水资源调度运行提供依据。  相似文献   

4.
小浪底水利枢纽灌溉塔是黄河北岸灌区引水的关键。根据枢纽泄水建筑物布置及调度方式和不库设计采用的运用方式,分析了灌溉塔前的水位变化,泥沙淤积、等引水条件,认为不同的泄水建筑物正常开启条件下灌溉塔不会被泥沙淤堵,塔前含沙量一般可满足引水要求,但运用中要注意排污清污。  相似文献   

5.
为克服传统量水方法水头损失大、技术复杂、经济成本高等问题,提出了一种基于水位和符号回归的灌区无干扰量水方法,并依据高邮灌区典型斗渠2012~2013年实测水位流量数据,对方法应用效果进行了评估。结果表明:符号回归优选出来的5组模型均能较好地估算渠道流量,模拟值与实测值均方根误差RMSE和平均绝对误差MAE分别为71.81~73.43,52.15~56.38m~3/h,调整决定系数超过0.8,说明模型能够较好地反映渠道水位流量关系,模拟精度较高。该方法精度可靠、应用简便、经济可行,在灌区量水方面具有较广的应用前景。  相似文献   

6.
黄河下游灌区农田灌溉制度与供需平衡分析   总被引:10,自引:1,他引:9  
在簸箕李引黄灌区上游和下游选择典型试验区,开展了连续两年的冬小麦一夏玉米连作种植模式下的田间试验观测,用模拟灌溉制度的计算机模型ISAREG对各试验处理进行模拟,验证了模型的模拟精度。依据模拟结果对现行灌溉制度进行了评价。模拟对比了灌区内3个县4个不同干旱程度典型年气候条件下10种主要作物的两种灌溉制度方案,包括充分灌溉和部分非充分灌溉方案,计算了不同方案的田间灌溉需水过程,分析了不同方案下灌区水资源供需平衡状况。研究表明,簸箕李灌区只有采用改进的田间灌水技术和有控制的非充分灌溉制度,才能使灌区供水和需水在平水年基本达到平衡。  相似文献   

7.
Ant Colony Optimization for Multi-Purpose Reservoir Operation   总被引:4,自引:1,他引:3  
In this paper a metaheuristic technique called Ant Colony Optimization (ACO) is proposed to derive operating policies for a multi-purpose reservoir system. Most of the real world problems often involve non-linear optimization in their solution with high dimensionality and large number of equality and inequality constraints. Often the conventional techniques fail to yield global optimal solutions. The recently proposed evolutionary algorithms are also facing problems, while solving large-scale problems. In this study, it is intended to test the usefulness of ACO in solving such type of problems. To formulate the ACO model for reservoir operation, the problem is approached by considering a finite time series of inflows, classifying the reservoir volume into several class intervals, and determining the reservoir release for each period with respect to a predefined optimality criterion. The ACO technique is applied to a case study of Hirakud reservoir, which is a multi-purpose reservoir system located in India. The multiple objectives comprise of minimizing flood risks, minimizing irrigation deficits and maximizing hydropower production in that order of priority. The developed model is applied for monthly operation, and consists of two models viz., for short-time horizon operation and for long-time horizon operation. To evaluate the performance of ACO, the developed models are also solved using real coded Genetic Algorithm (GA). The results of the two models indicate that ACO model performs better, in terms of higher annual power production, while satisfying irrigation demands and flood control restrictions, compared to those obtained by GA. Finally it is found that ACO model outperforms GA model, especially in the case of long-time horizon reservoir operation.  相似文献   

8.
通过膜下渗灌技术在新疆干旱灌区的应用,分析了膜下渗灌技术在新疆干旱灌区特点与优势,发现该技术具有:节约成本、增产、维护工作量小、节水等优势;与“小白龙”常压膜下滴灌、加压滴灌和常规小畦沟灌相比,每公顷增收分别为5373、4222.05、7776元;项目投资回收期为2.1年,经济效益显著,可在干旱灌区进行大面积推广应用。  相似文献   

9.
缺水型灌区水资源优化调度模型研究   总被引:3,自引:0,他引:3  
长江针对缺水型灌区的供水特点,以云南曲靖灌区为例,应用大系统分解协调原理,将整个系统设计为两层递阶控制结构;以运行费用和系统缺水量最小作为目标函数,建立了灌区库群系统水资源优化调度模型;对模型权重系数进行了率定;根据系统目标重要性的优先次序,确定了灌区优化配水矩阵;并采用模拟技术与优化技术相结合的途径,进行优化模型的求解,给出了优化决策算法的程序框图,所建模型符合曲靖灌区的实际情况,研究成果可为同类灌区水资源调度运行提供依据.  相似文献   

10.
Egypt has valuable experience with water user associations in irrigated agriculture. Internationally funded irrigation improvement projects aiming to increase irrigation efficiency have introduced water user associations at the branch-canal level alongside improvements to the infrastructure in the Central Delta of Egypt. In this article we review those water management practices in which these associations are expected to participate. Our main finding is that their role in these areas is minimal and that they are generally weak organizations. Either such organizations should be genuinely strengthened legally and politically, and given real responsibilities and resources, or the entire idea of participation should be abandoned.  相似文献   

11.
参与式灌溉管理模式科层化问题分析   总被引:4,自引:0,他引:4  
从管理模式的权限结构和交易成本视角出发,分析参与式灌溉管理模式科层化的内涵、成因及类别,探讨解决科层化问题的途径与方法。结果表明,理论上参与式灌溉管理模式在权限结构、决策方式和管理机制等方面表现为混合关系、共同决定和多种管理机制相融合的特点,但实践中却往往体现出等级制、层级决策、单一行政管理机制的科层化特征。基于节约交易成本的组织行为激励,政府凭借其权限控制权进行的选择性干预和农民用水户协会等组织的适应性反应是导致科层化问题的主要成因。将政府职责限定在公共服务范围内、完善法律体系支持成立非政府灌溉管理经营组织以及提高农民用水户协会等相关组织的自我管理能力是参与式灌溉管理模式得以可持续发展的关键所在。  相似文献   

12.
现代灌溉水肥调控原理与技术研究进展   总被引:2,自引:0,他引:2  
我国一般年份农业缺水约300亿m~3,农业水肥利用率主要指标相当于国际先进水平的60%~70%,农业缺水和面源污染问题日益突出,严重影响国家粮食安全和生态安全。本文综述了创新团队在现代灌溉水肥调控原理、技术与模式等方面所开展的研究工作进展。通过多年的研究,发展了现代灌溉施肥变量调控理论方法,提出了精量滴灌水肥高效调控技术、变量喷灌水肥高效调控技术、精细地面灌溉水肥高效调控技术等关键技术,构建了东北粮食主产区覆膜滴灌水肥精量调控技术模式、华北地下水超采区灌溉水肥高效调控技术模式和西北干旱区滴灌水肥盐协同调控技术模式,节水、增产和节肥效益十分显著。  相似文献   

13.
The Egyptian Ministry of Water Resources and Irrigation (MWRI) has expressed concern about the current high cost of the Irrigation Improvement Project (IIP) implemented in the “old lands” of the lower reaches of the Nile River. Because the IIP is financed through fees paid by the direct beneficiaries of the project, i.e., irrigation water users, these same Egyptian agricultural producers are especially sensitive to the higher than expected costs that the project has incurred to date. The objective of the current study is to evaluate whether this cost reduction is associated with any deficiency in irrigation performance. This Monitoring and Evaluation (M&;E) study aims to answer questions such as: Does reducing pump capacity and increased pump operation affect the farmers negatively? And, does the use of electricity instead of diesel fuel affect the farmers positively? Six indicators were used to compare new design criteria in the W10 and the IIP1 irrigation system designs, water savings, irrigation cost, irrigation time, night irrigation, and land savings. The W10 project design achieved the minimum actual operating cost per unit of area and per unit of water compared to the IIP1 project design on both Meet Yazied and El-Mesk Canals. The total cost per unit of area in the W10 project design is lower than IIP1 by 19.33% and 24.92% on the Meet Yazied and El-Mesk Canals, respectively. The total cost per unit of water in the W10 design is also lower than IIP1 on the Meet Yazied and El-Mesk Canals. Average irrigation time for rice and cotton crops cultivated in the W10 area are higher than average irrigation time for these crops cultivated in the IIP1 area for all locations on the Mesqa (head, middle and tail), because of increased pump operation in the W10 area (16 to 20 h d???1). The number of irrigation events at the head of the Sefsafa Canal in the W10 area is higher than on the Meet Yazied and El-Mesk Canals in the IIP1 areas because of the increased pump operation in the W10 area.  相似文献   

14.
在对灌区来水和需水随机性分析的基础上,建立了一种确定灌区灌溉用水保证率的计算模型。利用该模型不仅可以进行灌区评价,而且可用于灌溉用水设计,为灌区的规划和管理提供了较为科学的决策依据。文章最后以示例说明了模型的可行性。  相似文献   

15.
基于回归分析法构建标准化的自来水厂工程造价模型,包括单元构筑物建筑工程费用模型和自来水厂设备购置费用模型。同时结合自来水厂取水头部、其他类型建筑物及总平面布置费用造价分析,工程建设其他费用及预备费估算水厂造价。根据实际工程,对获得的模型进行校验。单元构筑物各自的建筑工程费用估算误差均控制在30%以内,符合项目建议书阶段的精度控制要求;自来水厂工程部分,实际设备购置费用估算误差为-11.30%;自来水厂造价整体造价估算误差率为4.03%。基于回归分析构建的自来水厂造价模型,能够应用于自来水厂的快速造价估算,并保证较好的估算精度。  相似文献   

16.
根据相关研究结论和田间试验结果,构建了精量灌溉中基于作物冠层红外温度和土壤水分等模糊决策模型,并进行了冬小麦田间试验的实际运行和结果考核.结果表明,冠层红外温度是一个较好的反映作物水分状况的灌溉决策指标;冬小麦日内冠气温差的变化规律是在10点和14点出现双峰现象,最佳灌溉决策时机应该考虑到这两点的观测数据.充分考虑作物的水分信息状况和土壤水分情况(田持的60%时),将可以使作物的灌溉决策和管理达到“适时“和“适量“.所开发的基于作物红外冠层温度的精量灌溉决策模型,可以在进一步的试验观测基础上进行改进和完善,有较强的通用性和实用性.  相似文献   

17.
地面灌溉的研究现状与发展趋势   总被引:1,自引:0,他引:1  
本文简要介绍了地面灌溉田面水流运动、灌水质量评价指标及灌水新技术和设备方面国内外研究现状,分析了目前存在的问题、并探讨了地面灌溉未来的发展趋势;指出今后应把简捷易用的地面灌溉水流运动模拟软件开发,不同地区和土壤条件下田间入渗参数的取值及其地面灌溉合理灌水技术指标,不同地区阶式水平畦灌、膜孔膜侧灌、长畦分段灌等低成本地面灌溉技术的标准化灌水技术指标,适合国情的地面灌溉的实时反馈控制技术和设备、激光平地设备、波涌灌溉控制阀、闸管等的开发作为研究重点。  相似文献   

18.
本文以我国十大区域灌溉需求指数为切入点,灌溉水经济价值为主要研究内容,在系统整编2000~2005年四种主要农产品成本收益资料的基础上,采用扣除非水成本法计算得出了十大区域四种主要作物灌溉水经济价值,揭示了作物适应性种植的地域性特征和规律性,提出粮棉作物种植的优势地区、种植布局以及政策扶持和倾斜的品种,为粮棉种植决策和维护国家粮食安全提供水资源方面的科学依据。  相似文献   

19.
周新国  温季 《水利学报》2001,32(3):0073-0077
本文对已有的浅井工程进行抽水试验、灌溉试验,经过理论分析,推导出了单井低压管道输水灌溉系统的最21-优出水量、最佳降深、最佳扬程、经济管径及田间多孔软管配水计算方法,确定了浅井灌溉费用最小、效益最大的浅井低压灌溉优化配套技术。  相似文献   

20.
奕永庆 《中国水利》2005,(15):41-43
余姚市推广水稻薄露灌溉技术,累计面积38万hm2,节水4亿m3,获"可持续发展在中国案例大赛"优秀案例称号.通过实践,"经济型喷滴灌"新思路采用PE塑管代替钢管、河网代替主管道、缩小灌区单元、水泵机组移动等措施,降低造价50%以上;科学利用不同水源,促进了绿色食品生产,增加了农民收入.通过"机埠转制"、人员奖励、政府投入、企业投入等多种措施,使放水员、水利技术员、农技员及广大农户提高了节水灌溉的积极性.  相似文献   

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