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1.
Recharge to the aquifer through seepage from irrigation canals is often quoted as one of the main causes for waterlogging
in Pakistan. In the design of drainage systems to control this waterlogging, rules-of-thumb are often used to quantify the
seepage from canals. This paper presents the option to use a groundwater model for a more detailed assessment. Groundwater
models may assist in evaluating the effect of recharge reducing measures such as interceptor drains along irrigation canals
and lining. These measures are commonly aimed at reducing the drainage requirement of adjacent agricultural lands.
In this paper an example is given of the application of a numerical groundwater model, aimed at assessing the effect of interceptor
drainage and canal lining in the Fordwah Eastern Sadiqia project, being a typical and well-monitored location in Pakistan.
The paper also presents references to other conditions. The model was used to obtain a better insight in the key hydraulic
parameters, such as the infiltration resistance of the bed and slopes of irrigation canals, the drain entry resistance of interceptor drains and the hydraulic conductivity of soil layers. The model was applied to assess the effectiveness and efficiency of interceptor drains under various conditions.
The results of the study show that the net percentage of intercepted seepage is too low to have a significant effect on the drainage requirement of the adjacent agricultural lands. Besides, the operation
of the system, with pumping required, is often an added headache for the institution responsible for operation of the system.
The marginal effect of interceptor drains and lining on the drainage requirement of adjacent agricultural land does not always
justify the large investments involved. It can be concluded that:
Relevant hydrological concepts and modelling parameters with respect to leakage from irrigation canals and interception by
interceptor drains are presented in a separate paper. 相似文献
| • | Use of rules-of-thumb to estimate components of the water balance of irrigation systems in designing drainage can be very misleading; |
| • | Interceptor drainage may cause induced seepage from irrigation canals, which is often an order of magnitude more than the net intercepted seepage; |
| • | Interceptor drains and canal lining do not significantly reduce the drainage requirements, or in other words, cannot prevent the need for the installation of a drainage system; |
| • | A numerical model can aid to evaluate proposed measures and strategies to alleviate water losses and drainage problems. |
2.
《Agricultural Water Management》2005,75(3):194-225
Agriculture is the main non-point polluter of groundwater in irrigated areas as fertilizers and other agrochemicals are the main contaminants in the water that drains out of the root zone to recharge the aquifer. Nitrates from fertilizers, dissolved in percolation losses from rice fields, are the source of pollution considered. The concentration of nitrates in the percolated water depends on the distributed field water and nitrogen balances over the area. Its concentration in the groundwater depends on the total recharge, pollution loading, groundwater flow and solute transport within the aquifer. The development and application of a GIS based decision support framework that integrates field scale models of these processes for assessment of non-point-source pollution of groundwater in canal irrigation project areas is presented. The GIS is used for representing the spatial variations in input data over the area and map the output of the recharge and nitrogen balance models. The latter are used to provide the spatially distributed recharge and pollutant load inputs to the distributed groundwater flow and transport models, respectively. Alternate strategies for water and fertilizer use can be evaluated using this framework to ensure long-term sustainability of productive agriculture in large irrigation projects. The development and application of the framework is illustrated by taking a case study of a large canal irrigation system in India. 相似文献
3.
The sustainability of the rice-wheat cropping system in an irrigated semi-arid area of Haryana State (India) is under threat due to the continuous rise in the poor quality groundwater table, which is caused by the geo-hydrological condition and poor irrigation water management. About 500,000 ha in the State are waterlogged and unproductive and the size of the waterlogged area is increasing. We analyse the hydrology and estimate seasonal net groundwater recharge in the study area. Rainfall is quite variable, particularly in the monsoon season, and the mean monthly reference evapotranspiration shows a high inter-annual variation, with values between 2.45 and 8.47 mm/day in December and May. Groundwater recharge analysis during the study period (1989-2008) reveals that percolation from irrigated fields is the main recharge component with 57% contribution to the total recharge. An annual groundwater table rise of 0.137 m has been estimated for the study area. As the water table has been rising continuously, suitable water management strategies such as increasing groundwater abstraction by installing more tubewells, using the groundwater conjunctively with good quality canal water, changes in cropping patterns, adoption of salt tolerant crops, changes in water-pricing policy, and matching water supply more closely with demand, are suggested to bring the water table down to a safe limit and to prevent further rising of the water table. 相似文献
4.
基于地下水均衡模型,分析了陕西泾惠渠灌区不同频率典型年的地下水均衡状况,结果表明降水入渗补给、渠系渗漏及田间灌溉入渗补给、井灌回归补给是灌区地下水的主要补给源,占总补给量的85.99%~82.89%;而人工开采是灌区地下水的主要排泄途径,农灌地下水开采量、人畜和工业用水开采量占总排泄量的69.7%~72.86%.以2010年为现状基准年,2020年为规划水平年,结合灌区发展规划,设置了4种不同的灌区发展情景模式,运用所建立的地下水均衡模型计算了不同情景模式下的地下水位埋深,其变化范围为0~0.07 m;以地下水位变幅最小为准则,得出了不同频率典型年合理的渠井用水比例范围为1.49~1.53,从而为灌区地下水资源的高效持续利用提供了依据. 相似文献
5.
美国德克萨斯州高地平原区地下水灌溉管理方法研究 总被引：2，自引：2，他引：0
《灌溉排水学报》2019,(1)
德克萨斯州高地平原区是美国灌溉和旱地作物的生产基地,其灌溉水源主要来源于奥加拉拉(Ogallala)地下水含水层。然而,自从1950年灌溉农业发展以来,由于对奥加拉拉含水层地下水的过度开采,使得区域地下水位严重下降,有些地区地下水位下降超过50 m。为了保护地下水资源和实现地下水可持续利用,2000年以来美国德克萨斯州高平原地区在节水压采方面开展了一系列工作,取得了较好的成效。采取的主要措施包括:用德克萨斯州高地平原蒸腾蒸发网络(The Texas High Plains Evapotranspiration Network, TXHPET)进行灌溉及地下水管理,改变作物品种,改进灌溉技术,改变种植结构,保护性耕作方法,加强降雨管理,将小部分灌溉农田转为旱作农田等。该区域1958年的灌溉面积为183万hm~2,1974年灌溉面积达到峰值,为242万hm~2;1989年灌溉面积降为159万hm~2,由于喷灌技术的推广应用,2000年灌溉面积恢复到187万hm~2。1958年大多数灌区为地面灌溉,仅有11%的灌溉面积为喷灌。1974年之后,灌溉总面积在减少,主要灌溉方式转为喷灌,中心支轴式喷灌面积稳步增长。自1989年之后,喷灌在该区域快速发展,2000年喷灌面积已占该区域灌溉面积的72%。早期的喷灌系统在较高压力下运行,自20世纪80年代,低压喷灌系统已全面使用。我国华北地区长期超量开采地下水与美国德克萨斯州高原区地下水超采情况及问题相似。兹系统介绍了美国德克萨斯州高地平原区在地下水超采情况下采取的综合措施拟为我国地下水超采地区的地下水管理工作提供技术与经验参考。 相似文献
6.
Jerome M. Schaack 《Irrigation and Drainage Systems》1986,1(1):93-99
The US Bureau of Reclamation has been constructing irrigation water distribution systems since the early 1900s in the 17 Western United States. The advent of this construction soon necessitated a means for preventing excessive seepage from some canals or portions thereof. Numerous types of linings have been installed including concrete, asphalt, masonry, buried plastic membrane, exposed membrane, compacted earth, etc., with varying degrees of success. The three most commonly used at the present are concrete, buried plastic membrane, and compacted earth. Although not a type of lining, buried pipelines are also used extensively and among other advantages they reduce seepage losses very significantly. 相似文献
7.
Assessing the groundwater dynamics and impacts of water saving in the Hetao Irrigation District, Yellow River basin 总被引：2，自引：0，他引：2
Water resources allocated to the agricultural sector in the Yellow River basin are being reduced due to severe water scarcity and increased demand by the non-agricultural sectors. In large-scale irrigation districts, the application of water-saving practices, e.g., improving the canal system, using water-saving irrigation technology and adjusting cropping patterns, is required for the sustainable agricultural development and the river basin environmental equilibrium. Adopting water-saving practices leads to lowering the groundwater table and to controlling salinity impacts related to excessive irrigation. However, assessing the effects of water-saving practices on the groundwater system requires further investigation. The Jiefangzha Irrigation Scheme of the Hetao Irrigation District is used as a case study for analyzing the temporal and spatial dynamics of the groundwater table. A lumped parameter groundwater balance model has been developed with this purpose and to assess impacts of various water-saving practices. The model was calibrated with monthly datasets relative to the non-frozen periods of 1997-1999 and validated with datasets from 2000 to 2002. Results indicate that canal seepage and deep percolation account for respectively 48% and 44% of the annual groundwater recharge. Groundwater discharge by direct evaporation and plant roots uptake represents 82% of the total annual groundwater discharge. After validation, the model was applied to assess the impacts of various canal and farm irrigation water-saving practices. It was observed that improvements in the canal system (e.g., canal lining, upgrading the hydraulic regulation and control structures, improving delivery schedules) might lower the groundwater table by 0.28-0.48 m, depending upon the level of implementation of these measures. Higher declines of the groundwater table are predicted when water-saving technologies are applied at both the canal and the farm systems. That decline of the water table favours salinity control and reduces capillary rise, thus reducing the groundwater evaporation and uptake by plant roots; that reduction may attain 128 mm. However, predictions may change depending on the way how water-saving measures are applied, which may be different of assumptions made; therefore, there is the need to perform a follow-up of the interventions in order to update predictions. Results indicate the need for appropriate research leading to improved irrigation management when the decline of the groundwater level will reduce groundwater contribution to vegetation growth. 相似文献
8.
我国北方灌区地下水资源演变与农田生态环境问题 总被引：4，自引：0，他引：4
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。 相似文献
9.
Combining hydrological modeling and GIS approaches to determine the spatial distribution of groundwater recharge in an arid irrigation scheme 总被引：2，自引：2，他引：0
Accurate quantification of the rate of groundwater (GW) recharge, a pre-requisite for the sustainable management of GW resources, needs to capture complex processes, such as the upward flow of water under shallow GW conditions, which are often disregarded when estimating recharge at a larger scale. This paper provides (1) a method to determine GW recharge at the field level, (2) a consequent procedure for up-scaling these findings from field to irrigation scheme level and (3) an assessment of the impacts of improved irrigation efficiency on the rate of GW recharge. The study is based on field data from the 2007 growing season in a Water Users Association (WUA Shomakhulum) in Khorezm district of Uzbekistan, Central Asia, an arid region that is characterized by a predominance of cotton, wheat and rice under irrigation. Previous qualitative studies in the region reported irrigation water supplies far above the crop water requirements, which cause GW recharge. A field water balance model was adapted to the local irrigation scheme; recharge was considered to be a fraction of the irrigation water losses, determined as the difference between net and gross irrigation requirements. Capillary rise contribution from shallow GW levels was determined with the HYDRUS-1D model. Six hydrological response units (HRUs) were created based on GW levels and soil texture using GIS and remote sensing techniques. Recharge calculated at the field level was up-scaled first to these HRUs and then to the whole WUA. To quantify the impact of improved irrigation efficiency on recharge rates, four improved irrigation efficiency scenarios were developed. The area under cotton had the second highest recharge (895 mm) in the peak irrigation period, after rice with 2,514 mm. But with a low area share of rice in the WUA of <1 %, rice impacted the total recharge only marginally. Due to the higher recharge rates of cotton, which is grown on about 40 % of the cropped area, HRUs with a higher share of cotton showed higher recharge (9.6 mm day?1 during August) than those with a lower share of cotton (4.4 mm day?1). The high recharge rates in the cotton fields were caused by its water requirements and the special treatment given to this crop by water management planners due to its strategic importance in the country. The scenario simulations showed that seasonal recharge under improved irrigation efficiency could potentially be reduced from 4 mm day?1 (business-as-usual scenario) to 1.4 mm day?1 (scenario with maximum achievable efficiency). The combination of field-level modeling/monitoring and GIS approaches improved recharge estimates because spatial variability was accounted for, which can assist water managers to assess the impact of improved irrigation efficiencies on groundwater recharge. This impact assessment enables managers to identify options for a recharge policy, which is an important component of integrated management of surface and groundwater resources. 相似文献
10.
T. K. Alexandridis A. Panagopoulos G. Galanis I. Alexiou I. Cherif Y. Chemin E. Stavrinos G. Bilas G. C. Zalidis 《Irrigation Science》2014,32(2):127-140
Despite being necessary for effective water management, the assessment of an irrigation system requires a large amount of input data for the estimation of related parameters and indicators, which are seldom measured in a regular and reliable manner. In this work, spatially distributed surface energy balance fluxes and geographical information systems analysis of multiple groundwater parameters were used to estimate water availability, supply, and demand, in order to calculate water-accounting indicators. This methodology was used to evaluate the performance of an irrigation system in the Pinios river basin (Greece) at two selected years of high and low water availability. Time series of archived satellite images and groundwater measurements have been used for past years to support comparative analyses, due to the limited availability of actual water measurements. The resulting maps from the proposed methodology show that the performance of the irrigation system varied across space and time due to differences in its characteristics and changes in its operation, driven by fluctuation of water availability and the response of stakeholders to water depletion. Irrigation districts with unsustainable water management were identified and, together with those with slow and/or limited groundwater recharge, were brought to the attention of water managers. The observed differences in the system operation between the wet and dry years were attributed not only to the hydrological conditions of each year, but also to the changing behaviour of farmers and the improvement actions of the water managers. 相似文献
11.
《灌溉排水学报》2019,(11)
【目的】准确获取阿克苏河下游区灌溉入渗补给系数,对该区灌溉入渗补给系数的影响因素进行分析,为绿洲带高强度人工灌溉模式下地表水地下水转化机理研究,提高研究区地下水数值模拟精度提供基础。【方法】选取阿克苏下游区不同灌溉制度、包气带厚度、土壤结构下代表性点进行野外取样及室内灌溉试验,并结合Hydrus-1d进行包气带水流数值模拟,通过改变灌溉制度、包气带厚度,应用Hydrus-1d模型计算该土壤结构下的灌溉入渗补给系数变化。在模型计算结果的基础上,首先分析灌溉制度、包气带厚度与灌溉入渗补给系数的关系;其后重点利用模型计算结合数理统计的方法分析土壤结构中影响灌溉入渗补给系数的主要因素。【结果】研究区内滴灌条件下灌溉入渗补给系数的范围为0.320～0.474;畦灌条件下灌溉入渗补给系数的范围为0.408～0.561,即不同灌溉制度下灌溉入渗补给系数不同;而伴随包气带厚度增大,灌溉入渗补给系数也随之减小;土壤结构对灌溉入渗补给的主要影响因素为土壤渗透系数、土壤体积质量、土壤初始含水率。【结论】根据室内试验结合数值模型计算出不同灌溉制度下的灌溉入渗补给系数变化范围,得出灌溉入渗补给系数的影响因素为灌溉制度、包气带厚度和反映土壤结构的土壤渗透系数、土壤体积质量及土壤初始含水率,为干旱区下游区灌溉入渗补给系数选取及后续研究提供理论依据。 相似文献
12.
In the semi-arid Brazilian Northeast, the exploitation of alluvial aquifers for irrigation and domestic supply to rural communities over the last 10 years has upset the traditional mechanisms of water resources management. In the Forquilha watershed (221 km2; 5°17″S, 39°30″W), the two main water resources are reservoirs (with a capacity exceeding 0.9-6.7 × 106 m3), used for domestic water supply only, and an alluvial aquifer (2.3 × 106 m3), used for irrigation and domestic water supply. From 1998 to 2006, the irrigated area with alluvial groundwater increased from 0 to 75 ha, and the fraction of population supplied through domestic water networks, using reservoirs and the aquifer, increased from 1% to 70%. Based on physical and socioeconomic issues, three main water territories have been defined (“Aquifer”, “Reservoirs”, and “Disperse Habitat”). Considering the next 30 years with a realistic population growth, three hypotheses regarding irrigated area (i.e., 0, 75, or 150 ha), and several possible water-management scenarios, hydrological balance models were built and used to simulate the different impacts on water resource availability and salinity. Simulation results showed that, in all cases, releases from the upstream main reservoir are necessary to keep reservoir salinity below 0.7 g L−1 and for guaranteeing domestic needs in the whole watershed. As a consequence, a management approach that takes into account the interrelations among the three territories is necessary. Moreover, the simulations showed that the area of irrigated fields cannot exceed the current extent (75 ha), or serious restrictions on water availability and salinity will take place. Moreover, important socioeconomic problems are expected, including a high cost of palliative water supply with tank trucks from external sources. 相似文献
13.
Waterlogging and salinization are major impediment to the sustainability of irrigated lands and livelihoods of the farmers, especially the smallholders, in the affected areas of the Indus Basin. These problems are the result of a multitude of factors, including seepage from unlined earthen canals system, inadequate provision of surface and subsurface drainage, poor water management practices, insufficient water supplies and use of poor quality groundwater for irrigation. About 6.3 million ha are affected by different levels and types of salinity, out of which nearly half are under irrigated agriculture. Since the early 1960s, several efforts have been made to improve the management of salt-affected and waterlogged soils. These include lowering groundwater levels through deep tubewells, leaching of salts by excess irrigation, application of chemical amendments (e.g. gypsum, acids, organic matter), and the use of biological and physical methods. However, in spite of huge investments, the results have in general been disappointing and the problems of waterlogging and salinity persist.This paper reviews sources, causes and extent of salinity and waterlogging problems in the Indus Basin. Measures taken to overcome these problems over the last four decades are also discussed. The results reveal that the installed drainage systems were initially successful in lowering groundwater table and reducing salinity in affected areas. However, poor operation and maintenance of these systems and provision of inadequate facilities for the disposal of saline drainage effluent resulted in limited overall success. The paper suggests that to ensure the sustainability of irrigated agriculture in the Indus Basin, technical and financial support is needed and enhanced institutional arrangements including coordination among different federal and provincial government agencies to resolve inter-provincial water allocation and water related issues is required. 相似文献
14.
《Agricultural Water Management》2006,86(3):283-287
The poor water quality of sub-surface drainage, hereafter drainage, water generated in the western San Joaquin Valley in California creates management challenges for farmers and water managers. Elevated concentrations of salt and trace elements in agricultural drainage limit the disposal options. In this constrained environment, determining the original source of drainage water is a crucial step in developing appropriate drainage management policies. Numerical modeling results of near-surface water-table fluctuations indicate that the substantial groundwater rise observed in the vicinity of the region's major water supply canal could not be attributed solely to seepage from overlying irrigated fields. An inverse solution approach is used herein to test the theory that seepage from the canal itself and/or that from surface water retention ponds (designed to protect the structure from flash floods) is responsible for an accentuated groundwater mound. The results suggest that canal seepage is the more likely source of non-agricultural aquifer recharge. 相似文献
15.
在我国北方地区,开展地表水与地下水联合运用,对合理利用水资源和综合治理旱涝碱,保证农作物高产稳产,具有十分重要的意义。地下水的开采,过少则不能满足农田灌溉;过多则会引起地下水径降低而出现漏斗区。正确的开采方法是:根据不同类型区域和不同水文年条件,分别计算出地下水采补平衡时和允许超采地下水位下降不同深度时,可得到的井灌开采强度。用此数值指导地下水的开发,可避免盲目开采带来的不良后果。该文提供的一些数值,是在人民胜利渠灌区得到的,其假设条件为地下水径流微弱、地下水补给仅受降雨和灌溉入渗的影响。所得到的数值可供类似地区参考。 相似文献
16.
《Agricultural Water Management》2001,46(3):215-230
In tropical, monsoon climates of South-East Asia, irrigation facilities supplement rain in the wet season and enable crops to be cultivated during the dry season. In the Dry Zone of Sri Lanka, 70% of the average annual rainfall of 1000 mm falls in a 3 month period. During the dry season, reference evapotranspiration has less rainfall — about 700 mm, indicating that much additional supply is meant to support crops, mainly paddy. In this climatic context, irrigation has dramatically changed the local environment, creating ecosystems quite similar to that of the wet zone to flourish. In these systems, recharge of shallow groundwater by percolation from irrigated fields, canals, and tanks, has provided a continuous supply of water for natural vegetation and homestead gardens. Much of the water used by this non-crop vegetation is beneficial. Growth of fruit and coconut trees can be quite profitable, while other trees enhance the environment.In 1998, IWMI performed a comprehensive water balance in the command area of the Kirindi Oya irrigation scheme, Sri Lanka, based on surface flow measurements, rainfall data, and estimation of crop water requirements. This water balance showed that evaporation consumed 78% of the total amount of water available for use. The amount of evaporation is split into process depletion (crops for 28%), direct evaporation from tanks (7%), inter-seasonal fallow (10%) and from non-crop vegetation for 55%.The main conclusion from this study is that perennial vegetation as the main component of non-crop vegetation, is a significant consideration in tropical humid environments in planning, management and performance assessment. Designers, managers, and researchers need to specifically incorporate the evaluation of evaporation by non-crop vegetation and perennial vegetation in their approach of water requirements. Further investigation is needed to estimate water consumption by land cover type to assess their respective beneficial use. 相似文献
17.
农业节水措施对地下水涵养的作用及其敏感性分析 总被引：1，自引：0，他引：1
以北京市大兴区为研究区,利用经校验的水平衡模型,通过调整灌溉满足率和灌溉水利用系数,探讨了不同农业节水措施对增加地下水补给量和减少地下水开采量的作用及其敏感性。结果表明,不同水文年型下,降低灌溉满足率及提高灌溉水利用系数都能减少地下水开采量,且降低灌溉满足率对减少地下净开采量的作用更为显著,有利于区域地下水涵养。在参数取值范围内,地下水净开采量对灌溉满足率的敏感性较大,而地下水补给量对灌溉水利用系数的敏感性较高。与提高灌溉水利用系数相比,对资源性缺水区域,采用先进节水技术,适度降低区域灌溉满足率,对促进水资源持续有效利用及加大地下水涵养具有更显著的效果。 相似文献
18.
宁夏引黄灌区历史悠久,是我国大型灌区之一。自实施宁夏引黄灌区续建配套与节水改造项目以来,灌区骨干工程安全状况有了较大改善,渠道综合调控能力不断增强,灌区节水意识进一步提高。良田渠灌域是青铜峡河西灌区的组成部分,通过渠道砌护及建筑物新建、维修等改造工程措施,提高灌溉水利用系数,减少引黄水量,完善渠道防洪体系,为渠道提供安全的行水条件。对灌区经济持续发展和工程效益的充分发挥起到推动作用,同时对改善渠道沿线生态环境和城市美化也具有积极意义。 相似文献
19.
Estimating groundwater recharge in response to increased atmospheric CO2 concentration and climate change is critical for future management of agricultural water resources in arid or semi-arid regions. Based on climate projections from the Intergovernmental Panel on Climate Change, this study quantified groundwater recharge under irrigated agriculture in response to variations of atmospheric CO2 concentrations (550 and 970 ppm) and average daily temperature (+1.1 and +6.4 °C compared to current conditions). HYDRUS 1D, a model used to simulate water movement in unsaturated, partially saturated, or fully saturated porous media, was used to simulate the impact of climate change on vadose zone hydrologic processes and groundwater recharge for three typical crop sites (alfalfa, almonds and tomatoes) in the San Joaquin watershed in California. Plant growth with the consideration of elevated atmospheric CO2 concentration was simulated using the heat unit theory. A modified version of the Penman-Monteith equation was used to account for the effects of elevated atmospheric CO2 concentration. Irrigation amount and timing was based on crop potential evapotranspiration. The results of this study suggest that increases in atmospheric CO2 and average daily temperature may have significant effects on groundwater recharge. Increasing temperature caused a temporal shift in plant growth patterns and redistributed evapotranspiration and irrigation water use earlier in the growing season resulting in a decrease in groundwater recharge under alfalfa and almonds and an increase under tomatoes. Elevating atmospheric CO2 concentrations generally decreased groundwater recharge for all crops due to decreased evapotranspiration resulting in decreased irrigation water use. Increasing average daily temperature by 1.1 and 6.4 °C and atmospheric CO2 concentration to 550 and 970 ppm led to a decrease in cumulative groundwater recharge for most scenarios. Overall, the results indicate that groundwater recharge may be very sensitive to potential future climate changes. 相似文献
20.
河套灌区井渠结合地下水数值模拟及均衡分析 总被引：2，自引：0，他引：2
建立了河套灌区三维地下水数值模型,用2006-2013年灌区实测地下水埋深资料对模型进行率定和验证,并在规划的井渠结合区内,设置3种不同井灌区灌溉定额和3种秋浇频率,组合共9种井渠结合节水情景,分别分析了9种节水情景下的地下水动态变化.结果表明:井渠结合后全灌区地下水埋深范围为1.863~2.029 m,较现状条件增加0.084~0.250 m;不同灌域结合区井渠结合后地下水埋深差别很大,解放闸结合区地下水埋深最大,为2.308~2.803 m,永济结合区地下水埋深最小,为2.079~2.455 m;井渠结合后,入渗补给量减少2.01×108 ~3.63×108 m3/a,潜水蒸发量减少1.69×108 ~3.03×108 m3/a. 相似文献