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1.
本文针对濮清南引黄补源灌区的具体情况,提出了引黄补源提灌与井灌联合运用工程系统、运用方式及运行管理等系列技术措施。  相似文献   

2.
根据作物的用水定额和灌溉面积等计算灌溉需水量,确定了小型提灌站泵的流量、扬程等相关参数,通过管径计算确定了输水管道直径,并根据相关参数设计了小型提灌站,为基层工作人员提供借鉴参考。  相似文献   

3.
黄土高原重力式地下滴灌水分运动模型与分区参数研究   总被引:6,自引:6,他引:0  
建立了重力式地下滴灌条件下的土壤水分运动模型,分析地下滴灌土壤水分入渗规律.对黄土高原不同分区的4种典型土壤、不同灌水技术要素条件下的地下滴灌土壤湿润体形态、滴孔处出流量及土壤土水势进行数值模拟得出:榆林紧砂土土壤导水率较大,向下渗漏过多,不适宜地下滴灌;安塞砂壤土、洛川中壤土、武功重壤土在相同灌水量下,供水压力与滴孔孔径对地下滴灌湿润体形态影响微弱,但对滴孔出流量有较大影响,因此在地下滴灌工程设计时,只需根据田块长度和渗水管损失设计孔径和供水压力,并采用较小供水压力,降低供水水池高度,减小工程量;对武功重壤土,孔径和供水压力较大时地下滴灌滴孔处土壤易饱和板结,宜采用较小的孔径和供水压力.  相似文献   

4.
低压输水管道灌溉技术是一种有效的节水灌溉措施,具有节水、节能、省地、省工、输水便捷、适应性强等特点,目前在我国平原井灌区应用较为普遍。山区自流灌区发展管灌技术,尚有许多问题需要研究解决。结合红旗渠灌区节水灌溉技术研究,我们对山区自流灌区发展管灌技术进行了一些有益的探索,就此项研究中取得的成功经验和存在问题作一介绍,和大家共同探讨。  相似文献   

5.
近年来,黄河水资源日趋紧缺,断流天数不断增加,断流时间不断提前,断流距离不断上延;同时,灌区用水量逐渐增加,水的供需矛盾突出。因此,在引黄灌溉时,借助于微机技术,及时对黄河来水与渠首可引水量进行预测,成为灌区用水管理中亟待解决的问题。好位山灌区在这方面的经济及做法。  相似文献   

6.
Eritrea’s coastal zone has been identified as an area of substantial development potential. About 14,000 ha of this 5 million ha area (i.e. <0.3%) has already been developed under a form of spate irrigation known locally as jeriff. This is a water diversion and spreading technique in which wadis (ephemeral streams), springing from Eritrea’s Central Highlands are diverted to irrigate land in the coastal plains. The system as it is applied in Sheeb, an area north-east of Asmara, characterised by agro-pastoral spate irrigation, is described. Under spate irrigation, crop growth is entirely dependent on the residual soil moisture stored in the soil profile. If the basin fields are flooded adequately, the resulting residual soil moisture is sufficient for two or sometimes three crop harvests. The spate irrigation system builds up land by depositing rich sediment on the fields, but therefore, the elevation of the irrigated lands rises every year. Moreover, the system requires huge numbers of trees annually for constructing diversion structures which are subsequently often washed away by heavy floods. In general, the overall irrigation efficiencies of spate schemes are only about 20% because of the difficulty of controlling floods and because water is lost by percolation, seepage and evaporation. Suggestions are made to improve the system and make it more sustainable: permanent flood diversion and distribution structures should be built to effectively divert the floods and to reduce water loss through percolation and seepage, and the basin fields should be properly levelled to distribute the floodwater uniformly over the entire field.  相似文献   

7.
由于新疆牧业灌区无电供应,水源无法过滤,实现滴灌工程难,目前采用地面灌溉。地形坡度大、灌水量多、大量水土流失。灌区下游排水不畅,洼地沼泽化面积剧增,地下水位上升导致土壤盐碱化,弃田面积逐渐扩大、种植面积萎缩。为了解决上述问题,充分利用地形落差,研制了自压滴灌工程过滤装置。同时渠道进水流量、调水池的调节流量、集水桶流量及系统流量之间建立了平衡关系。用实例说明不同地形落差与自压滴灌工程系统流量及过滤装置尺寸的计算过程。解决了自压滴灌工程水源的过滤、排沙、冲沙及自行冲洗等问题。为无电牧业灌区实现节水灌溉技术提供依据。  相似文献   

8.
Summary An array of irrigation systems are available which can be broadly classified as being gravity flow or pressurized. Pressurized irrigation systems provide better control on the amount of applied water and, in most cases, better irrigation uniformity than gravity flow systems. They also have a higher initial capital cost than gravity flow systems and an analysis is required to determine whether the improved performance of pressurized systems justifies the additional costs. An economic analysis was done on several irrigation systems which included consideration of farm management costs associated with a given irrigation system, shifts in crop yield and drainage volumes associated with the optimal management of each irrigation system, and costs associated with disposal of drainage waters. Cotton was selected as the crop for analysis. Irrigation uniformity is a significant determinant to the results. Although irrigation uniformities can be highly variable based on design, maintenance and management, a typical uniformity for each irrigation system was selected. For the conditions of the analysis, gravity flow systems were calculated to be more profitable than pressurized systems if there was no constraint on the amount of drainage water generated or cost for its disposal. Imposition of costs for drainage water disposal induced a shift whereby pressurized systems became more profitable than gravity flow systems.  相似文献   

9.
平原河网区改善水环境引水配水方案设计   总被引:1,自引:0,他引:1  
引水配水已成为当前改善平原河网区水环境状况的重要技术手段,而科学合理的引水配水方案无疑是提高水环境改善效果的重要依托。其设计原则、引水方式、配水方式以及相应流量的确定是整个引水配水方案设计的关键,而根据不同边界条件与不同流量状况确立的"间断引水"与"连续引水"、"同时配水"与"轮流配水"则较好地解决了引水配水方案设计与调度管理中的技术问题,其出发点在于最大限度地改善河网的水力条件,并以水力条件的改善促进河网水环境状况的日渐好转。  相似文献   

10.
基于多目标模糊规划的灌区多水源优化配置   总被引:2,自引:0,他引:2  
付强  肖圆圆  崔嵩  刘东  李天霄 《农业机械学报》2017,48(7):222-227,221
以黑龙江省和平灌区为例,构建基于多目标模糊规划的灌区多水源优化配置模型,该模型能够在提高农业灌溉用水净效益的同时有效减少农业灌溉水量,促进和平灌区多水源高效配置。采用具有非线性隶属度函数的模糊多目标规划求解模型,得到不同流量不同水源下的最优配水方案。结果表明:不同流量水平下水稻不同生育阶段均存在缺水现象,低流量下需从柳河水库引入外调水才能保证水稻的最小需水量。为保证灌区整体效益,按照引水工程、提水工程、井灌工程的先后顺序进行配水,并得到多目标配水模型在不同情景下的运行稳定情况。该模型可以高效地进行灌区多水源在作物各生育阶段的优化配置。  相似文献   

11.
It is well-known that major irrigation projects have a strong scale economy, handicapping irrigation development in sub-Saharan Africa (SSA) because of the difficulty in formulating large-scale projects. Using project-level investment cost and performance data of major and minor irrigation projects, this paper examines the causes of the economy of scale phenomenon. We find that strong scale economy exists not only for major but also for minor projects, i.e., small- and micro-scale, projects. This is largely because of the existence of indivisible overhead costs such as high-opportunity-cost human resources for planning, designing and engineering management and supervision. We also find that large differences between major and minor projects in the absolute level of overhead as well as construction costs creates a strong scale diseconomy and results in better performance of minor projects. The advantage of minor projects holds even when their higher risk associated with the water source is taken into consideration. We argue that there is an urgent need to promote irrigation development in SSA through developing minor projects, and to reduce the heavy burden of overhead costs by developing the capacity of human resources at the national, local and farmer levels in the fields of irrigation engineering, irrigation agronomy, institutional development, and micro water management technologies.  相似文献   

12.
以北京市大兴区和通州区境内的再生水灌区为研究对象,在分析灌区水文、气象、水资源开发利用与水量平衡状况、水利工程现状以及作物需水、灌溉水源等资料的基础上,采用系统工程的方法,通过构建多水源联合调度模型,统筹调度再生水、地表水、地下水等灌区内可利用水资源,使再生水灌区供水保证率得到显著提高,基本实现了地下水的采补平衡。提出了再生水灌区规划重点应围绕地表调蓄工程、田间配套工程、水网扩建工程以及灌区水资源管理信息化工程等4项内容。研究成果提升了再生水灌区规划的科学化水平,促进再生水资源高效合理利用。  相似文献   

13.
通过对山东省特别是鲁北地区引黄发展过程的研究,定量分析了鲁北地区大规模引黄灌溉前后地表径流系数的变化。结果表明,降雨量基本相同时,区域地表径流系数随引黄量的增大而增大。同时,大规模引黄灌溉后,增加了对浅层地下水的补给量,并且成为浅层地下水的主要补给来源。可利用黄河水替代深层地下水,控制和停止开采深层地下水或回灌深层承压含水层,能缓解淡水地下水漏斗扩大的问题。  相似文献   

14.
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   

15.
在华北引黄灌区内,大田作物的主要灌溉方式依然是畦灌。由于畦田规格过长过宽,导致灌溉水浪费严重,灌水效率低下。在平原县张庄管道灌溉示范区进行畦田灌溉试验,研究了黄河下游引黄灌区不同灌水技术参数组合对灌水质量的影响。利用地面灌溉水流运动的计算机模拟软件WinSRFR4.1,对不同规格畦田的灌水过程进行模拟,得出畦田灌溉的田间灌水效率和灌水均匀度,研究不同灌水技术参数组合对灌水质量的影响。综合考虑管道灌溉出水口规格与当地耕作农具尺寸等因素,模拟了多种畦长、畦宽、坡度和单宽流量下灌溉方案的灌水效果,结果表明,畦宽1.5m,畦长50~60m,坡度为0.3%畦田灌溉技术改进方案的灌水效率和灌水均匀度均提高到80%以上,灌水性能较优,建议在黄河下游引黄灌区内推广使用。  相似文献   

16.
Scheme irrigation management information system (SIMIS) is a decision support system for managing irrigation schemes. It can be used either as a management tool or as a training tool. The data needed for the technical and administrative management of the scheme can be stored, edited and displayed in various forms. They can then be used for helping in water management, calculating irrigation requirements, developing irrigation layouts, scheduling water deliveries, and keeping records of water consumption. The SIMIS approach is based on simple water balance models with capacity constraints. The user can simulate management alternatives, assess the results and try out new alternatives, until a satisfactory solution is found. SIMIS also helps in the administrative aspects of managing irrigation schemes (accounting, calculating water charges, controlling maintenance activities) and in assessing their performance.  相似文献   

17.
为揭示干旱区引黄灌区沟道退水滞后性规律,根据景电灌区沟道退水监测资料,采用交叉相关系数法和数据平移法确定灌区退水滞后时间,分析退水时空变化规律及其影响因素.研究表明,各退水口的年退水量差异不大,多年平均退水量约为4 622.3万m3,占灌溉引水量的31%.不同退水口之间的退水量差异较大,其中响水村占总退水的67%,五佛乡占总退水的30.6%,二期总一泵占总退水的2%.景电灌区不同退水口月退水量的主要影响因素为退水口控制面积和退水滞后时间,影响退水滞后时间的因素包括引水、降水、退水路径长度和人工开挖排水渠等.不同退水口的退水滞后时间在1~5个月之间,响水村退水滞后性较五佛乡和二期总一泵强,由灌溉和引水引起的退水滞后性有所差异.本研究所揭示的景电灌区退水滞后效应及其影响因素,可为灌区水资源合理配置与精准调控提供理论支撑.  相似文献   

18.
The cost constructing for irrigation is often given in $/ha. In deciding whether a project is worth undertaking, it is important to weigh the anticipated benefits against the expected costs. In this study, unit area construction costs based on the way of project water supply (gravity, pump) and scheme type (classic canal, flume, pipe) were calculated for the 211 irrigation projects operated and constructed by DSI (State Hydraulic Works) in Turkey. In a case study of the 27 irrigation schemes constructed by DSI in the Büyük Menderes and West Mediterranean basins, construction costs per unit area, irrigation ratio, and amount of unproductive costs were determined. As a result, though the area of 76383 ha was constructed for irrigation schemes, this area wasn??t under irrigation services with several various reasons; therefore, 641 million $US according to water supply way, and 574 million $US to the scheme type were unproductive investment for irrigation projects researched in the basins.  相似文献   

19.
随着经济社会的发展以及城镇化进程的推进,我国农村土地结构、人口结构、种植结构以及农村资本发生了巨大的变化,引发了农村土地的大幅度流转,催生了多种形式的农业经营主体。南方地区受自然条件、传统观念等方面的影响,农户配合度与参与度不高,南方灌区用水组织的内生动力、凝聚力较弱,终端用水管理体制也比较薄弱。新型经营主体对用水组织的供水质量提出了更高的要求,南方自流灌区的终端用水管理迎来了机遇与挑战。本文通过总结新型经营主体的经营特点,分析了新型经营主体在在农村水利设施的建设、管护与用水管理等方面对南方自流灌区终端用水管理的影响,从新型经营主体的参与、基层水管队伍的建设、水费计收机制的完善等角度提出科学有效的管理意见。  相似文献   

20.
Summary Effects of furrow irrigation designs, water management practices (irrigation scheduling, etc.), soil types and pesticide parameters on pesticide leaching were simulated. A hydraulic kinematic-wave irrigation model was used to estimate water infiltration for alternative furrow lengths and inflow rates. A one-dimensional simulation model then simulated the movement of pesticides through soils following furrow irrigation. Potential ground-water contamination by pesticides can be reduced by an integrated use of the best management practices (BMPs) such as careful selection and use of pesticides, efficient furrow irrigation designs and improved water management techniques (irrigation scheduling, etc.). Procedures for designing an appropriate furrow irrigation system for a particular site and pesticide, and selecting pesticides for a particular site, crop and furrow irrigation system are illustrated. These procedures are being used to develop decision support computer models for developing different BMPs for pesticide-agricultural management decisions.  相似文献   

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