河套灌区井渠结合数值模拟及水资源分析预报

随着黄河水资源逐年紧缺,河套灌区迫切需要提高区内的水资源利用效率。井渠结合采用抽取地下水和引黄水共同灌溉,在不减少灌溉用水的情况下减少了引黄水量,是一种切实有效的节水措施。应用Visual MODFLOW建立了河套灌区的地下水模型,通过对模型的率定与验证,较好地反映了河套灌区实际水文地质条件,可用来预测该地区地下水运动及水资源状况,分析该地区采取井渠结合节水措施后对地下水的影响。模型预测结果表明:河套灌区实施井渠结合节水措施后,可减少黄河引水约4.09亿m3,井渠结合区内生育期平均地下水埋深由2.17 m增至2.68 m,秋浇期由1.91 m增至2.82 m,冻融期由2.28 m增至2.50 m。     

人民胜利渠灌区水资源高效利用调控技术研究

在分析总结近几年灌区水资源高效利用调控理论与技术发展的基础上,提出适用于人民胜利渠灌区水资源的调控技术方案:作物种植结构调整和井渠用水比例调整,并建立引黄灌区地表水-地下水联合优化调度模型,定量分析其引、用、耗水关系及地下水变化规律.结果表明,人民胜利渠灌区通过采用作物种植结构调整和井渠灌水比例调整,从节水、经济、生态等方面均可以达到高效利用水资源的目的.     

基于线性规划和MODFLOW耦合技术的人民胜利渠灌区水资源优化配置研究

【目的】确定人民胜利渠灌区合理的农业水资源优化配置方案,为灌区水资源管理和机井布置提供科学依据。【方法】针对人民胜利渠灌区水资源分配不合理及灌区生态环境恶化问题,按照灌区地形地貌、工程类型和灌溉水源特点将灌区分为Ⅰ、Ⅱ、Ⅲ共3个计算单元,基于线性规划方法和MODFLOW地下水数值模型对灌区各计算单元进行不同水文年水资源优化配置,并模拟优化配置后地下水位动态变化。【结果】确定了不同水文年灌区的水资源优化配置方案:灌区计算单元Ⅰ、Ⅱ、Ⅲ区不同水文年的井渠比例有所不同,平水年井渠比分别为1/3.14、1/3.25、1/2.92,丰水年分别为1/3.47、1/3.66、1/3.24,枯水年分别为1/2.75、1/2.77、1/2.60;平水年计算单元Ⅰ区模拟地下水埋深相比初始埋深下降0.01 m,水资源总量基本处于平衡状态;计算单元Ⅱ、Ⅲ区模拟地下水埋深相对于初始埋深分别上升了0.12、0.15 m;丰水年灌区计算单元Ⅰ、Ⅱ、Ⅲ区模拟地下水埋深相比初始埋深分别上升了0.1、0.23、0.3 m;枯水年灌区计算单元Ⅰ、Ⅱ、Ⅲ区模拟地下水埋深相比初始埋深分别下降了0.17、0.08、0.04 m。【结论】线性规划方法和MODFLOW地下水数值模型相结合能较好地模拟灌区地下水流场和预测地下水动态变化趋势,进而确定合理的水资源优化配置方案。     

人民胜利渠灌区井渠结合灌溉初探

井渠结合灌溉是在不民胜利渠的灌溉实践中产生的，它即是灌区综合治理旱涝碱沙的有效措施之一，也是正确确定渠灌，井灌水量，地表水，地下水联合运用，调控，稳定地下水位和优化配置藻区水资源的前提，渠灌，井灌应油灌区管理单位统一管理，才能全面推广井渠结合灌溉，从而达到灌溉水资源的优化配置。     

基于采补平衡的河套灌区井渠结合模式及节水潜力

确定合理的渠井结合比以保证地下水采补平衡,是发展井渠结合灌溉、保证灌区节水和可持续发展的重点和难点。根据井渠结合区的地下水可开采量与井渠结合井灌区的灌溉用水量之间的平衡关系,建立地下水补给均衡模型。该模型考虑各级渠道输水、田间灌溉和降雨入渗对地下水的补给,地下水开采量则根据井灌区灌溉用水量确定,建立地下水补给与地下水开采量之间的均衡方程,通过求解该均衡方程,得到井渠结合区渠井结合比的合理范围在2.3~3.4之间。同时,通过局部敏感性分析方法,分析了该模型涉及参数中对渠井结合比影响程度较大的5个参数,敏感性从大到小依次为:地下水可开采系数、土地利用系数、渠道输水补给地下水系数、田间灌溉补给地下水系数、降雨补给地下水系数。进一步根据渠井结合比,计算了灌区实施井渠结合灌溉的节水潜力,结果表明,井渠结合全部实施后,灌区的节水潜力在3.4~4.6亿m~3,节水效果显著。     

小开河灌区地表水沙及地下水联合优化配置模型

水资源供需矛盾、地下水环境保护以及泥沙长距离输送是小开河灌区面临的3个重要问题。针对灌区水资源开发利用现状和长距离输沙的特点,以水资源配置的总体经济效益为目标建立了水量分配效益模型,以地下水合理埋深为目标建立了地下水位控制模型,并将当前水沙优化调度的具体措施模型化建立了输沙效果模型;利用分层序列法按水量模型、水量-水沙模型、水量-水沙-地下水模型的求解次序逐步将三个不同目标的模型耦合在一起,得出了50%及75%水平年时引黄水和灌区地表、地下水联合优化配置方案。该优化模型综合考虑了水资源利用的经济与环境问题,对促进小开河灌区以及黄河下游其他引黄灌区的可持续发展有参考价值。     

三江平原引水灌区优化模型及应用

三江平原地区现行的灌溉模式主要是以井渠灌溉为主,但仍存在地下水过度开采问题,而过境地表水却没有得到充分利用。针对三江平原现行灌溉模式存在的问题,提出运用引水灌溉来提高地表水利用率,并提出水资源优化配置模型。以期为三江平原灌区的水资源优化调配和生产实践提供参考。     

井渠结合类型灌区的可持续发展对策

分析了我国井渠结合类型灌区的发展与现状，指出了目前井渠结合类型灌区存在的主要问题；认为井渠结合类型灌区可以实现灌区内的水资源在空间和时间上的调节，要实现灌区的可持续发展，就必须研究和加强灌区内水资源统一管理和宏观调控的运行机制，充分发挥地下水库的调节作用。     

基于GIS的河套灌区井渠结合分布区的确定方法

实施井渠结合,合理开发利用地下水是河套灌区节水和控制土壤盐碱化的重要途径。运用ArcGIS分析了地下水矿化度和土壤岩性特征,采用空间分层的处理方法构建了地下水矿化度分区图,并结合灌区土地利用状况和农业灌溉用水要求确定了井渠结合区分布以及面积。结果表明,将矿化度数据分3个空间层处理是可行的,建立的矿化度分区图呈一定的空间变化特征。井渠结合区主要分布在乌兰布和灌域非沙漠带、解放闸灌域和永济灌域南部、义长灌域北部及其与乌拉特灌域、乌梁素海交界附近区域、乌拉特灌域尾部、灌区北部沿狼山山脉部分区域。井渠结合区约占整个灌区控制面积的45%。     

井渠结合灌区节水农业综合技术体系与示范

井渠结合是一种普遍的灌溉形式,目前,北方的这类灌区普遍存在着地表水与地下水不能合理调配、地下水过量超采所导致的水环境问题和灌溉效益不高的问题。而灌溉效益低下又进一步扩大了水资源的供需矛盾,使地下水的超采问题进一步加剧,严重制约着灌区经济的可持续发展和水资源的可持续利用。灌区应建立一种什么样的农业发展模式,走一条什么样的节水路线始终是一个研究的重点和难点。在山西晋中榆次区进行了试验与示范(项目区6667 hm2,其中示范区667 hm2,辐射区6000 hm2),就此介绍业已建立的井渠结合灌区(榆次区)节水农业综合技术体系,以及建设的示范区和节水效果。     

Analysis on groundwater table drawdown by land use and the quest for sustainable water use in the Hebei Plain in China

Increased water use in the Hebei Plain during the last decades has caused serious groundwater level decline and many geological problems which have become the biggest threat to social–economic sustainability. Thus, to determine the factors resulting in the groundwater decline and to develop a practical plan for long-term groundwater use appear to be necessary in this region. In this paper, a water balance model is used in conjunction with regression techniques to estimate the groundwater recharge coefficient and the specific yield (defined as the ratio of the volume of water that a saturated rock or soil will release by gravity drainage to the volume of rock or soil) and the groundwater withdrawn by different water use sectors and the corresponding drop in the water-table are analyzed. The decline in water-table by different crops and water economic benefit of crops are discussed in detail in order to suggest sustainable use of groundwater resources in the Hebei Plain. Finally, sample policy scenarios are developed to show how groundwater in the Hebei Plain could be used in a sustainable manner. In our study, it is found that agriculture is the major consumer of groundwater, with about 85% of the total groundwater withdrawals, and groundwater depletion is mainly caused by agricultural water use. Production of winter wheat exerts a great negative influence on the groundwater system. Winter wheat is the most water consuming crop and result in significant decline of groundwater table. Water economic benefit of winter wheat is lower than that of other crops and withdrawing winter wheat sown area is rational option to make sustainable use of groundwater. With far-sighted and regional planning, the limited water resource can be used sustainably to generate maximum social benefits. This paper will provide information necessary for land-use planning in a severe water shortage region where farmland is mainly irrigated by groundwater.     

An economic perspective on the potential gains from improvements in irrigation water management

In recent years, several researchers have introduced new terms describing irrigation efficiency to enhance the information available when evaluating water policy alternatives. Some of the definitions expand the physical boundary considered when evaluating water use, while others account for the changes in water quality that occur as drainage water is reused in an irrigated area. While the concepts of basin, global, and effective efficiency have enhanced our understanding of water use in agriculture, public officials may derive incorrect policy implications when reviewing empirical estimates of those measures, particularly if information describing the economic impacts of water use and allocation decisions is not available. For example, some authors suggest that when estimates of basin-wide efficiency approach 100%, there is little opportunity to save water by improving water management and achieving higher levels of classical, farm-level efficiencies in upstream portions of an irrigated region. However, there may be significant opportunities to increase the net values generated with limited water resources by improving the distribution of water among farmers and reducing the negative, off-farm effects of irrigation and drainage activities. Economic analysis is helpful in identifying those opportunities and in designing policies that encourage farmers and water agency personnel to improve water management practices in ways that enhance social net benefits.     

Integration of economic and hydrologic models: Exploring conjunctive irrigation water use strategies in the Volta Basin

We describe the development, calibration and preliminary application of a dynamically coupled economic–hydrologic simulation–optimization model ensemble for evaluating the conjunctive use of surface and groundwater in small reservoir-based irrigation systems characteristic of the Volta Basin, Africa. We focus on a representative small reservoir-irrigation system located in the Antakwidi catchment in Ghana. The model ensemble consists of the physical hydrology model WaSiM-ETH and an economic optimization model written in GAMS. Results include optimal water storage and allocation regimes for irrigated production, given conjunctive surface water and groundwater systems. The goal of our research, conducted within the GLOWA Volta project, is to develop a decision support system for improving the management of land and water resources in the face of potential environmental change in the Volta Basin.     

我国北方灌区地下水资源演变与农田生态环境问题

通过对北方灌区地下水形成机理及其演变态势的分析,认为气候变化和人类活动的负面效应是导致灌区与地下水有关的生态环境问题的主要原因,尤其是地下水资源量的衰减已经影响到了灌溉农业的可持续发展。针对以上问题,从水循环的角度提出充分利用灌区地下含水层的调蓄作用,通过地表水与地下水的联合利用控制水盐平衡、涵养地下水源是实现地下水资源永续利用、农田生态环境良性循环的有效途径。     

宁夏银北灌区井渠结合灌溉三维数值模拟与分析

为实现银北灌区水资源联合调度 ,减少引黄水量 ,充分利用地下水的目标 ,对选定典型区的地表水、地下水联合调度进行模拟 ,对井渠结合灌溉模式和运作方式进行了计算。通过三维的数值模拟计算发现 ,在规划渠系利用条件下 ,可以根据当地实际情况 ,在来水保证率低的春灌或冬灌期实施井灌 ,以控制地下水位 ,减少土壤返盐 ,也可以对部分农田采用集中井灌的方式 ,以提高用水效率。     

山东省引黄灌区农业节水技术应用研究

针对山东省引黄灌区的农业用水状况 ,提出引黄灌区需遵循引黄补源、以井保丰 ,井渠结合的基本农业生产用水思路 ,在区域范围内合理规划调控地表水、地下水 ,以保证灌区有限水资源发挥最大效益。并通过工程及节水配套的应用与集成 ,总结出黄河下游灌区农业节水发展模式     

基于2型模糊集的多目标农业-生态水土资源优化配置

针对西北干旱区灌区生态环境脆弱、水资源短缺、复杂不确定性等问题,以石羊河流域红崖山灌区为例,耦合2型模糊集、模糊可信度约束规划和多目标规划等理论方法,构建了基于2型模糊集的多目标农业-生态水土资源优化配置模型。模型以灌溉水损失最小、生态植被灌溉水满意度最大、生态植被灌溉水费用最小和主要粮食作物经济效益最大为目标,对红崖山灌区10个决策单元的地表水、地下水和粮食作物种植面积进行优化配置。求解模型得到不同可信度水平和不确定性程度下的水土资源优化配置方案。结果表明：耦合2型模糊集的模型能够提供丰富的配置方案,水量对可信度水平的敏感性高于不确定性程度,作物种植结构对可信度水平不敏感。以不确定性程度参数为0.5、可信度水平为0.7时为例,生态植被均通过地表水灌溉,作物通过地表水、地下水联合灌溉,玉米的产量和经济效益均大于小麦。相比前人研究,本研究考虑生态植被灌溉需求,优化结果更加真实合理。本研究可为决策者提供较为符合灌区实际的配置方案,为西北干旱区灌区现代化建设提供科学指导。     

An integrated hydro-economic modelling framework to evaluate water allocation strategies I: Model development

In this paper an integrated modelling framework for water resources planning and management that can be used to carry out an analysis of alternative policy scenarios for water allocation and use is described. The modelling approach is based on integrating a network allocation model (REALM) and a social Cost Benefit economic model, to evaluate the physical and economic outcomes from alternative water allocation policies in a river basin or sub-basin. From a hydrological perspective, surface and groundwater models were first applied to assess surface and groundwater resource availability. Then an allocation model was applied to reconcile the calculated surface and groundwater resources. From an economic perspective initially the value of water allocated to different uses in each demand centre within the system was estimated. These values were then placed in a social Cost Benefit Analysis to assess the economic consequences of different allocation scenarios over time and space. This approach is useful as it allows policymakers to consider not only the physical dimensions of distributing water, but also the economic consequences associated with it. This model is considered superior to other models as water is increasingly being seen as an economic good that should be allocated according to its value. The framework outlined in this paper was applied to the Musi sub-basin located in the Krishna Basin, India. In applying this framework it was concluded that competition for Musi water is very high, the transfer of water from agriculture to urban users is likely to grow in future and the value of water used in different agricultural zones is very low.     

山东省节水灌溉动态变化研究

节水灌溉是解决我国农业干旱缺水的根本性措施,它可以带来显著的经济、社会效益.山东省属水资源缺乏地区,农业用水量约占总用水量的74%,发展节水灌溉势在必行.鉴于此,对1996--2005年山东省有效灌溉面积、节水灌溉面积及二者比例的动态变化进行了分析.结果表明:1996-2005年山东省有效灌溉面积总体有所增加,增幅不大;节水灌溉面积有较大增长,平均每年增加9.314 1万hm2;后者占前者的比例逐年上升,平均每年增长1.903%.而各市有效灌溉面积、节水灌溉面积及二者比例的变化差异性比较明显.山东省整体的节水灌溉效果良好,但发展不够平衡,有些地区仍需加大推广力度.     

基于Pareto蚁群算法和3S技术的灌区水资源空间优化配置

为了解决灌区水资源配置中的信息采集方法落后和多目标模型求解易陷入局部最优等问题,通过伪随机并行搜索和最近邻域选择等策略对Pareto蚁群算法进行改进,然后将Pareto蚁群算法与3S技术耦合,以宁夏银北灌区为仿真对象,利用改进的Pareto蚁群算法计算灌区多目标、多约束的水资源空间优化配置模型,获得最优的井灌水量、渠灌水量、排水量以及最优的经济效益和灌排费用。基于Pareto蚁群算法和３S技术的灌区水资源空间优化配置,能加快算法的收敛速度,获得全局最优解,使优化结果更接近实际,对灌区的水资源宏观调度具有一定的参考价值。