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1.
A conceptual model of groundwater occurrence was developed for a dike-intruded aquifer system in M??kaha valley, O??ahu, Hawai??i, USA, and used to explain the impacts of water resource development on groundwater levels and streamflow. Time-series analyses were applied to two subsets of daily rainfall, total flow, and baseflow??from the third (1946?C1968) and fourth (1968?C1991) periods of development??to evaluate changes in streamflow response. Autocorrelation, cross-correlation, squared coherency and phase functions were used to estimate the decorrelation lag time, and the correlation length, linearity with frequency, and frequency response delay between rainfall and streamflow. The decorrelation lag time for total flow and baseflow declined by 16?C20?days (d). The correlation length between rainfall and streamflow declined 4?C7?d for total flow and 10?C13?d for baseflow. The squared coherency function indicates an overall decline in linearity between rainfall and total flow across most frequencies. The changes in hydrologic response following increased water-resource development is consistent with a model of groundwater depletion resulting in less groundwater discharge and more induced groundwater recharge. Changes in streamflow response are inconsistent with observed changes in rainfall and imply that streamflow decline is more likely to be the result of groundwater pumping. 相似文献
2.
Yumi Iwasaki Kimihito Nakamura Haruhiko Horino Shigeto Kawashima 《Hydrogeology Journal》2014,22(8):1841-1855
Assessing factors that influence groundwater levels such as land use and pumping strategy, is essential to adequately manage groundwater resources. A transient numerical model for groundwater flow with infiltration was developed for the Tedori River alluvial fan (140 km2), Japan. The main water input into the groundwater body in this area is irrigation water, which is significantly influenced by land use, namely paddy and upland fields. The proposed model consists of two models, a one-dimensional (1-D) unsaturated-zone water flow model (HYDRUS-1D) for estimating groundwater recharge and a 3-D groundwater flow model (MODFLOW). Numerical simulation of groundwater flow from October 1975 to November 2009 was performed to validate the model. Simulation revealed seasonal groundwater level fluctuations, affected by paddy irrigation management. However, computational accuracy was limited by the spatiotemporal data resolution of the groundwater use. Both annual groundwater levels and recharge during the irrigation periods from 1975 to 2009 showed long-term decreasing trends. With the decline in rice-planted paddy field area, groundwater recharge cumulatively decreased to 61 % of the peak in 1977. A paddy-upland crop-rotation system could decrease groundwater recharge to 73–98 % relative to no crop rotation. 相似文献
3.
A combined-water-system approach for tackling water scarcity: application to the Permilovo groundwater basin,Russia 总被引：1，自引：1，他引：0
The suitability of a combined water system (CWS) is assessed for meeting drinking-water demand for the city of Arkhangelsk (northwestern Russian Federation), instead of using the polluted surface water of the Northern Dvina River. An appropriate aquifer system (Permilovo groundwater basin) was found and explored in the 1980s, and there were plans then to operate an abstraction scheme using traditional pumping methods. However, the 1980s planned water system was abandoned due to projected impermissible stream depletion such that complete interception of the cone of depression with the riverbed would cause the riverbed to become dry. The design of a CWS is now offered as an approach to addressing this environmental problem. Several sets of major pumping wells associated with the CWS are located on the banks of Vaymuga River and induce infiltration from the stream. The deficiency of the stream flow in dry seasons is compensated for by pumping from aquifer storage. A numerical model was constructed using MODFLOW-2000. The results of the simulation showed the efficiency of the compensation pumping. The streamflow depletion caused by the CWS is equal to the minimum permissible stream flow and is lower than the depletion projected by the abandoned plan. Application of the CWS in the Permilovo groundwater basin makes it possible to meet water demands during water-limited periods and to avoid environmental problems. 相似文献
4.
Khan Mahfuzur R. Michael Holly A. Bresnyan Edward W. Yu Winston 《Hydrogeology Journal》2022,30(6):1899-1910
The Kosi Fan region of India and Nepal hosts a productive aquifer system. Regional hydrology is highly seasonal, and both groundwater and surface water are used for irrigation. Groundwater depletion is not currently occurring, but there is concern that plans to increase groundwater irrigation will reduce river baseflow, potentially affecting downstream water users. This study presents a model-based analysis of the impacts of groundwater withdrawal on dry-period streamflow and evaluation of management alternatives. A sensitivity analysis was performed in which a range of model parameters were tested around a best-estimate, base-case scenario. A high-reduction scenario was then developed which combined the factors that produced the greatest pumping-induced reduction in dry-season baseflow. Management strategies for 2.5, 5, and 10-km no-pumping buffers around the rivers were tested for the base-case and high-reduction scenarios. Simulations show that groundwater withdrawal equivalent to 30% and 60% of dry-season streamflow for the Kosi and Mahananda rivers, respectively, reduces the current dry-season flow by less than 4%. In the base-case scenario, simulated dry-season baseflow reduction is 1.8% and 2.6% for the rivers, respectively; these reduce to ~1% with a 2.5-km buffer zone. For the high-reduction scenario, dry-season baseflow reductions are 4.7% and 7.0% with no buffer; these reduce to 1.3% and 0.9% with a 5-km buffer for the Kosi and Mahananda rivers, respectively. The small reductions in baseflow relative to the total amount of pumping are due to a pumping-induced increase in rainfall recharge, thus the effects of additional pumping are mitigated.
相似文献5.
Groundwater recharge sets a constraint on aquifer water balance in the context of water management. Historical data on groundwater and other relevant hydrological processes can be used to understand the effects of climatic variability on recharge, but such data sets are rare. The climate of the Canadian prairies is characterized by large inter-annual and inter-decadal variability in precipitation, which provides opportunities to examine the response of groundwater recharge to changes in meteorological conditions. A decadal study was conducted in a small (250 km2) prairie watershed in Alberta, Canada. Relative magnitude of annual recharge, indicated by water-level rise, was significantly correlated with a combination of growing-season precipitation and snowmelt runoff, which drives depression-focussed infiltration of meltwater. Annual precipitation was greater than vapour flux at an experimental site in some years and smaller in other years. On average precipitation minus vapour flux was 10 mm y?1, which was comparable to the magnitude of watershed-scale groundwater recharge estimated from creek baseflow. Average baseflow showed a distinct shift from a low value (4 mm y?1) in 1982–1995 to a high value (15 mm y?1) in 2003–2013, indicating the sensitivity of groundwater recharge to a decadal-scale variability of meteorological conditions. 相似文献
6.
Estimation of groundwater recharge using water balance coupled with base-flow-record estimation and stable-base-flow analysis 总被引：1，自引：0，他引：1
In this paper, the long-term mean annual groundwater recharge of Taiwan is estimated with the help of a water-balance approach coupled with the base-flow-record estimation and stable-base-flow analysis. Long-term mean annual groundwater recharge was derived by determining the product of estimated long-term mean annual runoff (the difference between precipitation and evapotranspiration) and the base-flow index (BFI). The BFI was calculated from daily streamflow data obtained from streamflow gauging stations in Taiwan. Mapping was achieved by using geographic information systems (GIS) and geostatistics. The presented approach does not require complex hydrogeologic modeling or detailed knowledge of soil characteristics, vegetation cover, or land-use practices. Contours of the resulting long-term mean annual P, BFI, runoff, groundwater recharge, and recharge rates fields are well matched with the topographical distribution of Taiwan, which extends from mountain range toward the alluvial plains of the island. The total groundwater recharge of Taiwan obtained by the employed method is about 18 billion tons per year.An erratum to this article can be found at 相似文献
7.
地表水与地下水相互转化是中国西北干旱内流盆地水循环的显著特征,转化机制研究是盆地水循环规律认知和水资源可持续管理的重要基础。以我国西北干旱内流河黑河流域中游的张掖盆地和盐池盆地为研究区,建立了黑河主干河道时变水平衡模型和地表水地下水耦合数值模型,研究了长周期水文变化和人类活动双重影响下地表水与地下水转化机制,得到如下认识:（1）补给条件由以天然条件下河流渗漏为主的线状补给演变为以河流与引水渠道渗漏的线状补给和灌区田间入渗面状补给,排泄条件由以泉水溢出和天然湿地排泄演变为以泉水溢出与地下水开采为主的排泄。（2）张掖盆地黑河干流河道入渗段和溢出段大致以G312 大桥为界,亦称为地表水与地下水转化的转折点。莺落峡—G312 大桥段为悬河渗漏段,河道入渗补给主要受控于进入河道的实际过水量。其中,莺落峡—草滩庄段河道入渗补给率为28.20 %;草滩庄—G312 大桥段河道入渗补给量与河道过水量的关系可用分段函数表达,河道过水量大于或等于0.37×108 m3/mon时呈幂函数关系,小于则呈线性函数关系。G312 大桥—正义峡段为地下水溢出段,其中G312大桥—平川大桥段地下水溢出量约占全部溢出量的70%,溢出峰值出现在高崖水文站下游约6 km处,其单长溢出量可达0.46 m3/(s·km)。（3）研究区是一个相对完整的河流—含水层系统,近31年来经历了连枯和连丰的水文变化,地下水补给排泄条件及与地表水转化机制均发生了相应的变化。地表水与地下水转化最强烈的地区为张掖盆地中部的黑河—梨园河倾斜平原。1990—2001 年连枯期,灌区引水量总体逐年减少,以河道入渗和渠系渗漏为主的补给量平均以0.06×108 m3/a速率减少,农田灌溉面积增加导致灌溉用水增加,地下水开采量显著增加,地下水水位逐年下降,储存量累计减少5.77×108 m3,地下水溢出量平均减少0.16×108 m3/a;而2002—2020 年连丰期,灌区引水量总体逐年减少,河道入渗量呈增加趋势,地下水总补给量平均增加0.15×108 m3/a,灌溉面积继续扩大,农灌开采量随之增加,以河道入渗量增加为主导,地下水水位持续上升,储存量累计增加5.45×108 m3,地下水溢出量平均增加0.08×108 m3/a。总之,补给和排泄条件变化较大,地下水储存量先减后增,地下水溢出总量变化较为平缓,反映了该区巨厚含水层系统的巨大调蓄功能。（4）位于张掖盆地东部的诸河倾斜平原地下水水位长期处于持续下降状态,这是由于地表水开发过度,补给量锐减。黑河侵蚀堆积平原地下水水位基本稳定。30 多年来盐池盆地倾斜平原地下水水位长期处于持续下降状态,这是由于移民开垦导致地下水过量开采。（5）内流盆地天然悬河入渗段是珍贵的地下水补给通道,无论连枯期还是连丰期,河道实际过水量是河道渗漏补给量的关键,保护上游天然河道和一定的河道实际过水量是内流盆地水资源可持续管理的关键。 相似文献
8.
Lihe Yin Guangcheng Hu Jinting Huang Dongguang Wen Jiaqiu Dong Xiaoyong Wang Hongbo Li 《Hydrogeology Journal》2011,19(8):1563-1575
Groundwater recharge is a key factor in water-balance studies, especially in (semi-)arid areas. In this study, multiple methods were used to estimate groundwater recharge in the Ordos Plateau (China), including reference to water-table fluctuation, Darcy’s law and the water budget. The mean annual recharge rates found were: water-table-fluctuation method (46??09?mm/yr); saturated-zone Darcian method (17??4?mm/yr); and water-budget method (21??09?mm/yr). Generally, groundwater-recharge rates are higher in the eastern part of the plateau where the land surface is covered by permeable sand that is favorable for infiltration. Along with results from previous studies using the empirical method, the chloride-mass-balance method, the unsaturated-zone Darcian method and the hydrograph-separation method, groundwater recharge rates were compared. There is no one method that would consistently produce the largest or smallest estimate of annual recharge for all groundwater systems. The largest recharge estimates were usually determined using the unsaturated-zone Darcian method and the smallest estimates were usually determined using the chloride-mass-balance method. Comparison of multiple methods is found to be valuable for determining the range of plausible recharge rates and for highlighting the uncertainty of the estimates. 相似文献
9.
The dependence of stream depletion by seasonal pumping on various hydraulic characteristics and engineering factors 总被引：3，自引：2，他引：1
Compensation pumping is used to alleviate deficiencies in streamflow discharge during dry seasons. Short-term groundwater pumping can use aquifer storage instead of catchment-zone water until the drawdown reaches the edge of the stream. The capacitance is a complex, dimensionless parameter of an aquifer system that defines the delayed effect on streamflow when there is groundwater pumping. This parameter is a function of aquifer hydraulic characteristics, pumping time, and distance between the well and stream edge; the latter can involve stream leakance and vertical leakance of an associated aquitard. Three typical hydraulic cases of combined water systems (major catchment-zone wells close to the stream and compensation pumping wells) were classified depending on their capacitance structure (i.e. the relationship between surface water and groundwater): (1) perfect hydraulic connection between the stream and aquifer; (2) imperfect hydraulic connection between the stream and aquifer; and (3) essentially imperfect hydraulic connection between the stream and the underlying confined aquifer. The impact of various hydraulic characteristics and engineering factors on stream depletion was examined by conceptual and numerical modeling. To predict the suitability and efficiency of a combined water system application, regression tests were undertaken on unit stream depletion and capacitance, and power dependencies were defined. 相似文献
10.
Anomalies found when apportioning responsibility for streamflow depletion are examined. The anomalies arise when responsibility is assigned to the two states that contribute to depletion of Beaver Creek in the Republican River Basin in the United States. The apportioning procedure for this basin presumes that the sum of streamflow depletions, computed by comparing simulation model runs with and without groundwater pumping from individual states, approximates the streamflow depletion when both states are pumping. In the case study presented here, this presumed superposition fails dramatically. The stream drying and aquifer-storage depletion, as represented in the simulation model used for allocation, are examined in detail to understand the hydrologic and numerical basis for the severe nonlinear response. Users of apportioning procedures that rely on superposition should be aware of the presence and likely magnitude of nonlinear responses in modeling tools. 相似文献
11.
Yun Huang Bridget R. Scanlon Jean-Philippe Nicot Robert C. Reedy Alan R. Dutton Van A. Kelley Neil E. Deeds 《Hydrogeology Journal》2012,20(4):783-796
Understanding groundwater-pumpage sources is essential for assessing impacts on water resources and sustainability. The objective of this study was to quantify pumping impacts and sources in dipping, unconfined/confined aquifers in the Gulf Coast (USA) using the Texas Carrizo-Wilcox aquifer. Potentiometric-surface and streamflow data and groundwater modeling were used to evaluate sources and impacts of pumpage. Estimated groundwater storage is much greater in the confined aquifer (2,200?km3) than in the unconfined aquifer (170?km3); however, feasibility of abstraction depends on pumpage impacts on the flow system. Simulated pre-development recharge (0.96?km3/yr) discharged through evapotranspiration (ET, ～37%), baseflow to streams (～57%), and to the confined aquifer (～6%). Transient simulations (1980–1999) show that pumpage changed three out of ten streams from gaining to losing in the semiarid south and reversed regional vertical flow gradients in ～40% of the entire aquifer area. Simulations of predictive pumpage to 2050 indicate continued storage depletion (41% from storage, 32% from local discharge, and 25% from regional discharge capture). It takes ～100?yrs to recover 40% of storage after pumpage ceases in the south. This study underscores the importance of considering capture mechanism and long-term system response in developing water-management strategies. 相似文献
12.
Estimating ground-water recharge from streamflow records 总被引：3，自引：2，他引：1
The purpose of this paper is to estimate ground-water recharge based on the investigation of the balance between ground-water recharge and discharge from streamflow hydrographs. Two methods of hydrograph analysis are employed in a case study of Cho-Shui River basin, Taiwan. The first is the recession-curve-displacement method, which assumes the linearity of the master recession curve while the profile of the ground-water head distribution is nearly stable. The second method is the base-flow-record estimation, which uses a relatively arbitrary procedure to estimate a continuous record of ground-water discharge (baseflow) under the streamflow hydrograph. Through implementing these two methods, the annual rates of ground-water recharge and infiltration in the area of Cho-Shui River basin are examined as our case study. Results showed that the discharge calculated by the method of base-flow-record estimation is about 16% average less than the recharge calculated by the recession-curve-displacement method in the mountain region. 相似文献
13.
降水和人工灌溉是黑河中游浅层地下水重要的补给来源。长期以来入渗补给量评价采用经验参数法,但没有成熟的监测方法和实证数据。采用人工溴示踪法研究黑河中游不同灌溉条件和不同深度条件下的地下水入渗补给规律。结果表明:研究区大气降水条件下包气带溴离子含量峰值年均运移距离为21.25 cm,年平均入渗补给量为11.93 mm,入渗补给系数为0.1;大水漫灌条件下包气带溴离子含量峰值年均运移距离为86.51 cm,年平均入渗补给量为148.7 mm,入渗补给系数为0.16;小水漫灌条件下包气带溴离子含量峰值年均运移距离为46.35 cm,年平均入渗补给量为 53.81 mm,入渗补给系数为0.07;滴灌条件下年包气带溴离子含量峰值年均运移距离为41.72 cm,年平均入渗补给量为52.6 mm,入渗补给系数为0.11。人工溴示踪剂应投放在包气带水分单向入渗下行区,一般西北内陆盆地在地表3 m以下为宜。此研究成果可为黑河流域地下水资源评价提供实证参数,对西北内流盆地地下水水资源量与合理开发利用的科学认识具有重要意义。 相似文献
14.
The interaction between groundwater and surface water in northern Shaanxi is quite complicated and frequent under the influence of regional hydrogeological condition and human intervention. These performances bring serious challenges to regional water resources assessment and utilization. The river baseflow process at Gaojiabu Station in windy desert region, Gaoshiya and Caoping Station in loess region were taken as research objects, and their variation trends and change points in the river baseflow series were analyzed in this paper. In addition, to explore the cause of the baseflow change, this research compared their correlations with precipitations in the same area respectively from two aspects of flow variation and multi timescale characteristics. The results show that: ①groundwater recharges for river flow in windy desert region significantly exceed those in loess region; ②baseflows of all the rivers in the study area reducing significantly are mainly determined by human intervention such as the extensive pumping of groundwater; ③periodic changes of baseflow in each station response closely to precipitation change on meso-scale and small-scales; ④precipitation-runoff relationships in windy desert regions are much more complicated and unstable than loess region, which is mainly because of its more significant impact from groundwater storage and the lateral recharge change. Under the changing environment, the water cycle in windy desert regions would be in complexity and variability. Therefore, it is recommended that, groundwater changes need to be considered in regional water resources assessment. 相似文献
15.
The water balance for the Basin of the Valley of Mexico and implications for future water consumption 总被引：2，自引：0，他引：2
The Basin of the Valley of Mexico is a closed basin of 9600?km2, where average annual precipitation (1980–85) is 746?mm (226.7?m3/s). Calculated actual evapotranspiration is 72–79% of the precipitation. The surrounding mountain ranges of the Sierra de Las Cruces, Sierra Nevada, and Sierra Chichinautzin are the main recharge areas for the enclosed Basin, in decreasing order. Calculated recharge rate is a maximum of 19?m3/s in the Metropolitan Zone, whereas a recent estimate of the groundwater exploitation rate indicates that 51.35?m3/s is being withdrawn from the Basin aquifer systems, resulting in a deficit of more than 30?m3/s. Taking into account infiltration processes by leaking water-supply systems, the calculated deficit is reduced to 20.5?m3/s. Overexploitation of the natural aquifer systems is also indicated by an average annual decline of 1?m of the potentiometric levels of the shallow groundwater systems. Possible solutions include: (1) the use of surface runoff water (unused amount in 1995?:?17.6?m3/s) for consumption purposes, which is currently pumped to areas outside the Basin; (2) an increased number and capacity of treatment plants; (3) the renovation of the leaky water-distribution network; (4) the reinjection of treated water; and (5) possible exploitation of deep regional aquifer systems. 相似文献
16.
陈崇希 《水文地质工程地质》2020,47(5):1-4
Dupuit（1863年）提出的模型是“圆岛状含水层稳定井流模型”，这个模型只有侧向湖海边界条件，而不涉及上边界降水入渗补给条件。因此，Dupuit模型只能在旱季用于地下水井流试验求取含水系统的参数，而不能够用于预测。文章发展Dupuit潜水井流模型，考虑地面均匀稳定入渗补给（蒸发排泄示为其负值）作用。以质量守衡原理为基础，假定渗流服从Darcy定律并满足Dupuit徦定，建立极坐标下的地下水流微分方程，再依边界条件建立相应的流量方程和水位方程。这些方程为具地面入渗补给条件下井流试验求取水文地质参数以及预测相应条件下地下水抽水的效果，提供了基础条件。讨论了引入Dupuit假定对本问题解析研究可以降维（略去z变量）带来好处的同时，在地下水分水岭附近及抽水井附近可能出现偏离Dupuit假定，建议在抽水试验求取含水层参数时，观测孔的部署要尽量回避这些区段。 相似文献
17.
利用地下水数值模型MODFLOW和非饱和带水平衡模型对处于半干旱半湿润沙丘地区(Sand Hills)地下水位进行了模拟,并分析了含水层补排水量,河流与地下水补排关系,以及区域水平衡过程。揭示了独特沙丘地形和土壤特性对地下水补排量的影响。模拟结果表明,入渗率大、非饱和带厚的沙丘有利于降水入渗补给,减少了地下水蒸散发损失。加上下覆含水层具有良好的地下水储水空间,是该地区储存丰富的地下水量,以维持河流稳定流量,供给众多湖泊和湿地的原因。该研究对我国地下水资源评价和生态环境脆弱地区水资源保护具有指导意义。 相似文献
18.
The city of Seoul is home to more than 10 million people in an area of 605 km2. Groundwater is abstracted for public water supply and industrial use, and to drain underground facilities and construction
sites. Though most tap water is supplied from the Han River, the quantity and quality of groundwater is of great concern to
Seoul's citizens, because the use of groundwater for drinking water is continuously increasing. This study identifies the
major factors affecting the urban water budget and quality of groundwater in the Seoul area and estimates the urban water
budget. These factors include leakage from the municipal water-supply system and sewer systems, precipitation infiltration,
water-level fluctuations of the Han River, the subway pumping system, and domestic pumping. The balance between groundwater
recharge and discharge is near equilibrium. However, the quality of groundwater and ability to control contaminant fluxes
are impeded by sewage infiltration, abandoned landfills, waste dumps, and abandoned wells.
Electronic Publication 相似文献
19.
针对常用的利用降水入渗系数法确定的降水入渗补给量不随降水频率等因素而变化的弊端,利用郑州市地下水均衡试验场地中渗透仪长时间观测的系列资料,通过对降水—降水入渗补给量进行系统响应分析,建立了4种岩性、5个水位埋深的年际和月际的降水—降水入渗补给响应函数.研究结果表明,根据当期及前期的年、月降水量数据,利用系统响应分析法建立的降水入渗补给函数能比较准确地计算相应地区的降水入渗补给量. 相似文献
20.
以大通河流域享堂水文站1950~2005年实测径流数据为基础,综合运用趋势分析、累积距平、R/S分析、Morlet小波分析、降水-径流深度双累积曲线等数理统计方法,研究了大通河流域径流的年内分配、年际变化和周期振荡特征、并定量分析了气候因素和人类活动因素对径流变化的影响。结果表明:（1）大通河径流年内主要集中在510月,占年径流总量的82%左右。1950~2005年,大通河流域年径流呈微弱减少趋势,递减率为-0.55×108m3/10a（R2=0.025,P=0.249）,Hurst指数为0.58,表明未来一段时间内径流仍可能呈减少趋势;（2）1950~2005年,大通河流域年径流在27a时间尺度上周期震荡明显,经历了"多-少-多-少-多-少-多"7个循环交替;（3）大通河流域降水-径流深度双累积曲线在1994年发生显著偏移,1994年之前径流变化主要受降水影响,1994年以后,径流变化主要受人类活动影响。 相似文献