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1.
This paper will visually show, through the use of historic and contemporary photographs, that the National Reclamation Act is a cornerstone of growth in the West. The irrigation works constructed under the federal reclamation program provided a stable water supply for crops, transforming the desert to the farmlands, and continued with the development of cities, businesses, and communities. Hydropower, a by-product of water development, initially operated irrigation pumps and lighted homes, and now powers industries. Salt River Project (SRP), as one of the first multi-purpose reclamation projects authorized by the federal government, provided irrigation water to the settlers of the Salt River Valley at the beginning of the twentieth century. Over 100 years later, SRP continues that tradition and is still delivering water to its shareholders and customers, but now in an urban setting.  相似文献   

2.
This paper introduces a combined modelling approach using a simple water budget model (THC-model) and a 3D reservoir sedimentation model (MOHID Water) to adapt reservoir operation and visualise their effects on the sediment deposition. By this, an effective combined sediment-water management can be identified under semi-arid conditions for dry, median and wet years. Results are presented for the reservoirs of the Tuyamuyun Hydro-Complex (THC), which is located in the lower Amu Darya River. The determination of the actual and usable reservoir storage volume shows that siltation will significantly adversely affect the ability of the in-stream Channel Reservoir to regulate seasonal demand for both irrigation and municipal water supply. However, modelling scenarios results confirm the effectiveness of adapted operation rules for the THC reservoirs and show that the operation of large dams could be modified according to a combined sediment-water management. The experience gained during this study emphasizes the fact that the concept of a combined reservoir management of sediments as well as water can be an efficient measure to improve the sustainable long-term use of reservoirs and to contribute towards a safe water supply in water crisis regions.  相似文献   

3.
The Samanalawewa and Udawalawe reservoirs were built to harness the hydro-energy and irrigation potentials of the Walawe river in Sri Lanka. The recently completed Samanalawewa reservoir primarily generates hydropower while the Udawalawe reservoir, which was built in the 1960s, supplies water mainly for irrigation. With the addition of the Samanalawewa reservoir, located upstream of the Udawalawe reservoir, the Government of Sri Lanka is planning to increase the irrigated area of the Udawalawe reservoir. The Samanalawewa reservoir is expected to act as an additional storage for irrigation water supply. A study was carried out to investigate the operational behavior of these two reservoirs. The model used in the study is based on stochastic dynamic programming (SDP) and simulation techniques. Since, the direct application of SDP for two reservoirs is limited by the dimensionality of the problem, a sequential decomposition method is employed in the model. The algorithm employed breaks down the system into single-reservoir subsystems and subsequently, each subsystem’s operation is individually optimized using a SDP based optimization model and then simulated using a reservoir operation simulation model. The results indicate the usefulness of optimization techniques in planning reservoirs and deriving operational policies for them. The inclusion of the Samanalawewa reservoir reduces the irrigation water supply deficits at the Udawalawe reservoir.  相似文献   

4.
Agricultural water is delivered by open irrigation canals in system of reservoirs with a widespread distribution in South Korea. Traditional irrigation management problems include water distribution systems with less capacity than the peak demand, irregular delivery rates, and low irrigation efficiency and uniformity. It is necessary to strategically compare the estimated irrigation demands with the actual water supplies for decision making in order to maintain the water supply according to the demand. Accurate measurement and monitoring of water distribution systems is essential in order to solve the problems of water efficiency and availability. Auto water level gauges installed at the head and tail sections of each irrigation canal in the Dongjin River were used to measure the discharge during irrigation periods. In this study, we introduced an approach to assess the water delivery performance indicators of the open irrigation canals, which is essential for identifying the key issues for water management improvement. The irrigation efficiencies according to the water delivery performance indicators were measured with an automatic water gauge in the irrigation canals and were calculated from the spatial and temporal distribution of the water supply for the lack of planning in water delivery. The calculated performance indicators are useful to understand the irrigator behavior and general irrigation trends. Analysis of the results yielded insights into possible improvement methods in order to develop water management policies that enable irrigation planners to improve the temporal uniformity and equity in the water distribution.  相似文献   

5.
Salt River Project (SRP) was established in 1903 to deliver water to farms on about 250,000 ac (100,000 ha) located in South-Central Arizona. While SRP continues to deliver water to the entire area, today only about 10% of that land is still in agriculture. The remainder has been urbanized. Urbanization of the vast majority of water service area has caused SRP to rethink and adjust every aspect of its business, from daily operation and maintenance to the overarching issues of liability and public involvement. Some of the issues being addressed and lessons learned are addressed in this paper.  相似文献   

6.
水库作为重要的蓄水和供水工程,对城乡供水安全起着极其关键的作用。干旱时期,水库可能由于前期蓄水不足满足不了后期的用水需求,这就需要及早作出预警,以便采取应对措施。本文以永康市的杨溪水库为研究对象,界定了黄色、橙色、红色供水预警等级,采用长系列(1965-2009)逆时序逐日调节计算得出历年逐日水库所需蓄水量成果,并对45年成果进行统计分析,确定了杨溪水库黄色、橙色、红色三条预警线及各预警线的浮动上限。本研究成果能够指导干旱期水库供水运行管理工作,使区域的经济社会不因缺水产生过度影响,确保区域平稳有序度过不同程度的干旱期。  相似文献   

7.
为解决复杂流域水资源配置和水库群生态调度问题,以闸坝众多的沙颍河流域为研究对象,以流域关键断面的生态基流为基础,建立以“保证河道生态用水,优先生活用水”为目标的水资源配置模型。以近年用户的实际用水为基准年的需水水平,在丰、平、枯、特枯来水条件下,应用改进大规模线性规划方法求解,得到水库生态调度控制线和运行规则,以及地表水资源分配方案,并以枯水年85%来水条件进行验证。结果表明,与原常规调度相比,水库生态调度可充分利用可调水量的时空分布以及水库群的调控能力,更有效地提高沙颍河流域关键断面生态用水的保证率。研究为沙颍河流域水资源综合管理提供了技术支撑和决策支持。  相似文献   

8.
在湖南省已建水库资源总量、分布、水质以及相关城市供水现状与需水预测等大量资料的基础上,分析了水库水资源重新配置和城市供水紧缺的关键要素。在此基础上应用模糊数学多级多因子综合评价原理与方法,对湖南省目前29座城市的江湖水资源与已建67座靠近城市的大中型水库资源,给出了科学的定量评价。同时建立了“水库富水评价”、“城市水资源短缺评价”、“水库向城市供水方式评价”3个通用模式。  相似文献   

9.
在对汕尾市水文水资源情况调查分析基础上,基于MIKE BASIN数字平台构建了汕尾市水资源优化配置模拟模型。采用四级流域套县为计算单元,以河流、水库和山塘为供水水源,对基准年与规划水平年(2020年)在不同保证率下、不同需水推荐方案和供水推荐方案情况下,分别进行水资源供需平衡分析,从而使得城镇生活用水、农村生活用水、工业用水和农业灌溉用水及生态用水获得优化配置,以满足汕尾市规划水平年各类需水要求。  相似文献   

10.
Irrigated agriculture experienced a water supply shock during a drought in southern India in 2002-2003. In this paper, hotspots of agricultural change were mapped and put in the context of hydrology and water management. Time series of MODIS imagery taken every eight days before (2001-2002) and during (2002-2003) the supply shock were combined with agricultural census data to document changes in cropping patterns in four large irrigation projects in the downstream sections of the Krishna and Godavari River basins (total command area 18,287 km2). The area cropped in rice in the four irrigated command areas decreased by 32% during the drought year, and rice production in the two districts that experienced the largest flow reductions fell below production levels of 1980. The irrigation project that showed the largest change in double cropped area (−90%) was upstream of the Krishna Delta. In the Krishna Delta, large areas changed from rice-rice to rice-gram double cropping. Historical water management contributed to the vulnerability of rice production to drought: the main reservoir in the system was drained to dead storage levels by the end of each growing season over 1968-2000, with little carryover storage. The land cover change maps suggested that the lower Krishna Basin has experienced a “hard landing” during basin closure, and revised management strategies that account for the new flow regime will be required to maintain agricultural production during droughts.  相似文献   

11.
长江是中国最重要内陆水运通道之一。近年来,人类活动(梯级水库建设和人工采砂)严重影响了长江上游河道河床演变规律。通过分析长江上游2005至2017年的水沙实测资料,对比长江上游梯级水库联合运行前后(2012年前后)发现,梯级水库群下游年内水文过程与泥沙输运量受水库群运行的影响较大。梯级水库拦沙作用使长江上游河段年均推移质和悬移质较水库群建成前分别减少了87%和98.5%,水库群下游泥沙补给大幅减小引发河床冲刷、粗化,河床表层床沙中值粒径较水库群建成前明显增大。人工大面积采砂破坏长江上游河道河床粗化表层,形成局部挖沙坑,造成河床形态异常演变。总体来看,梯级水库清水下泄与采砂监管将使水库群下游河道表层粗化层更加稳定,河床演变逐渐趋近稳定。  相似文献   

12.
东营市拥有丰富的土地资源,现有灌溉面积14.2万hm^2,随着工农业生产的发展,需求量越来越大;黄河水资源日益紧张,黄河断流的影响影响也越来越大,因此,针对东营引黄的实际,提出了如下引黄供水的对策;进行灌区老化工程技术改造;修建平原水库;充分利用灌溉间隙,引黄蓄灌源;加强经济调控,合理调整水价;节约用水;严格控制退水,充分利用退水。  相似文献   

13.
This paper describes a two-part methodology for managing the risk posed by water supply variability to irrigated agriculture. First, an econometric model is used to explain the variation in the production value of irrigated agriculture. The explanatory variables include an index of irrigation water availability (surface storage levels), a price index representative of the crops grown in each geographical unit, and a time variable. The model corrects for autocorrelation and it is applied to 16 representative Spanish provinces in terms of irrigated agriculture. In the second part, the fitted models are used for the economic evaluation of drought risk. Inflow variability in the hydrological system servicing each province is used to perform ex-ante evaluations of economic output for the upcoming irrigation season. The model's error and the probability distribution functions (PDFs) of the reservoirs’ storage variations are used to generate Monte Carlo (Latin Hypercube) simulations of agricultural output 7 and 3 months prior to the irrigation season. The results of these simulations illustrate the different risk profiles of each management unit, which depend on farm productivity and on the probability distribution function of water inflow to reservoirs. The potential for ex-ante drought impact assessments is demonstrated. By complementing hydrological models, this method can assist water managers and decision makers in managing reservoirs.  相似文献   

14.
系统动力学以反馈控制理论为基础,处理高阶次、非线性、多重反馈、复杂时变的系统问题,广泛应用于水资源、城市水环境规划中。科学合理的需水预测是规划社会经济建设规模和发展速度的重要依据。针对济宁市水资源和社会经济现状与发展要求,以实现水资源供需平衡为目标,建立需水量预测系统动力学模型,通过变量调控、方案设计及节水效果评估,为节水管理提供决策信息。研究表明,建立的模型是有效的,可以全面客观地使济宁市社会经济发展获得良好的可持续性。  相似文献   

15.
以拉萨河下游河谷地区为研究对象,依据1989-2010年拉萨、墨竹工卡气象站气象资料和Landsat卫星遥感影像提取的主要作物(青稞、冬小麦及油菜)种植面积,计算不同典型年份研究区总灌溉需水量;结合拉萨水文站1989-2010年径流序列资料,分析区域灌溉用水的供需平衡.结果表明:拉萨河谷地区的种植模式以粮食作物为主,河谷区种植面积在1990-2010年间增长约8%,作物种植结构没有发生显著性的变化.农作物种植面积的增加引致灌溉需水量大幅度增加,2010年的灌溉需水量达到16亿m3,比1990年增长约35%,青稞为灌溉需求最大的作物.河流径流量及灌溉用水需求的季节性变化存在差异,每年4-6月灌溉供需关系较为紧张,灌溉量占径流量近10%~20%,每年12月至次年4月正值河流枯水季,尽管该期间灌溉需水量较低,但对水资源造成的压力也是不容忽视的.拉萨河谷地区水资源供需关系较为紧张.  相似文献   

16.
随着人口的增长和经济的发展,生活和生产需水日渐增多,水资源供需矛盾日益突出,而用水效率低、用水浪费现象也没有得到有效的控制,我国水资源当前所面临的严峻形势要求我们必须对水资源进行公平而合理的分配,提高水资源的利用效率,缓解供需矛盾。章水是赣江的一级支流,做好支流的水量分配工作是做好整个赣江流域水量分配工作的前提。本文首先构建了多层次半结构性多目标模糊优选模型,并以章水为例,用该模型对其水资源在各用水区域之间进行了分配,旨在对这种水量分配方法进行探讨的实践,以期为赣江流域水量分配工作提供一种可行的参考方法。  相似文献   

17.
本研究考虑海河流域经济社会发展格局及水资源时空分布特点,以全国主体功能区规划和生态功能定位为依据,根据不同区域的资源环境特点及河湖生态系统特征,以水资源保护问题及需求为导向,结合规划近远期目标和控制指标要求,统筹谋划并构建了海河流域水资源保护"两廊、四区、六带"的宏观战略格局.作为海河流域水资源保护规划与管理的顶层设计内容,也将为构建海河流域河湖健康保障体系提供支撑.  相似文献   

18.
Highly productive, irrigated agriculturecan be found in California's Central Valleymade up of the Sacramento, San Joaquin, andTulare Lake basins. High water tablesthroughout much of the San Joaquin andTulare Lake portions of the Valley threatenthis highly productive region. Due totopographic and environmental constraintsmuch of the region is currently withoutdrainage. In 1990 State and Federalgovernment agencies combined to produce areport that outlined possible steps to dealwith the drainage issue. These stepsincluded: 1) Source control (practices toreduce the amount of drainage water); 2)Drainage reuse; 3) Evaporation systems; 4)Land retirement (cease irrigation); 5)Groundwater management; and 6) Discharge tothe San Joaquin River. General backgroundinformation to the history and hydrology ofthe Valley as well as a discussion of thefeasibility and constraints of providingdrainage by discharging drain water to theSan Joaquin River are presented. Inaddition a general discussion of thetechnical and political limitations ofproviding drainage in the River arediscussed.  相似文献   

19.
【目的】预测城市的生活、工业、农业用水的需水,对城市的规划、经济发展以及供水系统的管理及扩建提供可靠依据。【方法】使用水平衡分析法及线性回归分析和大量的数据运算,通过线性回归分析现状年及2013—2017年用水量分析了海伦市用水现状并预测了2020年需水量。【结果】2020年海伦市城镇居民生活用水为774.66万m~3,农村居民生活用水量为1 622.32万m~3,2020年海伦市工业需水量为0.061亿m~3,2020年海伦市农业需水总量为3.64亿m~3。【结论】预测年2020年供水量大于需水量。  相似文献   

20.
利用地下水库调蓄水资源的若干措   总被引:6,自引:0,他引:6  
文章分析了国内外利用地下水库的现状,认为目前我国应从利用地下水库调蓄洪水、城市雨水、南水北调中线工程调水着手。当前我国利用地下水库调蓄水资源还存在一些技术和管理上的问题,对拟建区的可行性论证,现场试验研究,地下水库的维护与运行管理应该受到重视。建议进行两项示范工程,即利用地下水库调蓄南水北调中线工程引水,利用含水层调蓄城市雨水,取得利用地下水库调蓄水资源的系统经验和理论,在我国广泛推广。  相似文献   

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