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1.
Using groundwater levels to estimate recharge 总被引：24，自引：4，他引：24
Accurate estimation of groundwater recharge is extremely important for proper management of groundwater systems. Many different
approaches exist for estimating recharge. This paper presents a review of methods that are based on groundwater-level data.
The water-table fluctuation method may be the most widely used technique for estimating recharge; it requires knowledge of
specific yield and changes in water levels over time. Advantages of this approach include its simplicity and an insensitivity
to the mechanism by which water moves through the unsaturated zone. Uncertainty in estimates generated by this method relate
to the limited accuracy with which specific yield can be determined and to the extent to which assumptions inherent in the
method are valid. Other methods that use water levels (mostly based on the Darcy equation) are also described. The theory
underlying the methods is explained. Examples from the literature are used to illustrate applications of the different methods.
Electronic Publication 相似文献
2.
高照山 《吉林大学学报(地球科学版)》1987,(2)
凌源—建昌一带是辽宁西部主要干旱少雨地区,研究这一地区基岩地下水的分布规律,具有重大经济意义。本文从综合分析辽宁西部水文地质调查资科入手,对该地区基岩地下水类型及岩石富水性和褶皱束、盆地、断裂及不整合接触带富水性以及该地区补给径流排泄条件等问题进行了讨论。特别是深入分析了碎屑岩类裂隙孔隙水、碳酸盐类岩石裂隙岩溶水、带状裂隙水、层状裂隙水的赋存特点。 相似文献
3.
Vertical groundwater velocities can be estimated based on directions of groundwater thermal gradients. Temperature-depth profiles were obtained from 12 monitoring wells at 3 different times of the year (Fall, Winter, and Spring) in West Lafayette, Indiana (USA) mainly on the Purdue University campus. Microsoft Excel Solver was used to match plots of groundwater temperature distribution in the wells with published type curves in order to find a dimensionless parameter β, from which vertical groundwater velocities were obtained. The vertical groundwater velocities found in the monitoring wells ranged from 0.92 to 4.53 cm/yr. Clay-rich aquitards presented greater vertical groundwater velocities than outwash aquifers. The highest groundwater velocities occurred in the Spring while the lowest were during the Winter. This method was found to be especially useful in glacially-derived materials with varying hydraulic conductivities for estimating vertical groundwater velocities in-situ. 相似文献
4.
Aquifer remediation for a contaminated site is complex, expensive, and long-term. Groundwater modelling is often used as a tool to evaluate remedial alternatives and to design a groundwater remediation system. Groundwater modelling can also be used as a useful process to identify aquifer characteristics and contaminant behaviour that are not realized prior to modelling, to help diagnose what happened and why it happened at contaminant sites. Three real-world modelling cases are presented to demonstrate how groundwater modelling is applied to help understand contamination problems and how valuable the improved understanding is to decision-making and/or to remedial design. 相似文献
5.
6.
Multiple age tracers were measured to estimate groundwater residence times in the regional aquifer system underlying southwestern Oman. This area, known as the Najd, is one of the most arid areas in the world and is planned to be the main agricultural center of the Sultanate of Oman in the near future. The three isotopic age tracers 4He, 14C and 36Cl were measured in waters collected from wells along a line that extended roughly from the Dhofar Mountains near the Arabian Sea northward 400 km into the Empty Quarter of the Arabian Peninsula. The wells sampled were mostly open to the Umm Er Radhuma confined aquifer, although, some were completed in the mostly unconfined Rus aquifer. The combined results from the three tracers indicate the age of the confined groundwater is < 40 ka in the recharge area in the Dhofar Mountains, > 100 ka in the central section north of the mountains, and up to and > one Ma in the Empty Quarter. The 14C data were used to help calibrate the 4He and 36Cl data. Mixing models suggest that long open boreholes north of the mountains compromise 14C-only interpretations there, in contrast to 4He and 36Cl calculations that are less sensitive to borehole mixing. Thus, only the latter two tracers from these more distant wells were considered reliable. In addition to the age tracers, δ2H and δ18O data suggest that seasonal monsoon and infrequent tropical cyclones are both substantial contributors to the recharge. The study highlights the advantages of using multiple chemical and isotopic data when estimating groundwater travel times and recharge rates, and differentiating recharge mechanisms. 相似文献
7.
Theme issue on groundwater recharge 总被引：1，自引：0，他引：1
8.
Gordon James MacMillan 《Hydrogeology Journal》2007,15(4):823-826
9.
辽河三角洲处于陆地和海洋的结合部,蕴含丰富的资源,具有十分重要的战略地位。项目通过三年的时间,查明了辽河三角洲地区主要含水层结构:第四系含水层系统(Q)、明化镇组含水层系统(Nm)、馆陶组含水层系统(Ng)。通过设立动态监测网,建立、完善地下水动态监测体系,实现地下水位和水质的实时监测;地下水水位动态:第四系松散岩类孔隙水较为稳定,水位动态变化不大;上新近系明化镇组和馆陶组地下水,受人类活动影响较大,由于多年连续大量开采,地下水位逐年下降,已形成了2个区域性地下水降落漏斗。地下水水质动态:第四系上更新统(Q3)浅层水Cl-、SO42-、Na+及矿化度持续升高,高矿化度水分布面积扩大,水化学类型复杂化,氯化物型和钠型水分布面积增大,向周边扩散;明化镇组和馆陶组地下水,水质优良,变化不大。针对地下水超采,注重水资源合理配置,适当减少新近系地下水资源的开采,充分利用地表水资源的对策。 相似文献
10.
Fort Morgan Peninsula is an attached portion of a dynamic barrier complex in the northern Gulf of Mexico and is a large tourist
area that brings in a significant amount of revenue for Alabama. Many of the hotels and tourist attractions depend on the
groundwater as their water supply. The over-withdrawal of groundwater and saltwater intrustion will have a negative impact
on the ecology, tourism and economy if groundwater resources are not properly monitored and managed. In this study a calibrated
groundwater flow model was used to analyze the sustainability of groundwater resources at Fort Morgan Peninsula. Detailed
flow budgets were prepared to check the various components of inflow and outflow under different water use and climatic conditions.
The results indicated the locations where groundwater was over-pumped and subjected to saltwater intrusion, or will be subjected
to saltwater intrusion under a range of projected water use and climatic conditions. 相似文献
11.
12.
通过历时13年的长春市地下水水质的监测工作,对长春市地下水污染现状及污染趋势作了分析,结果表明,长春市潜水污染重,化学组合中Cl~-、SO_4~(2-)、NO_3~-、COD、总硬度、矿化度在很多地方出现高含量,且上升趋势明显;承压水在市中心集中开采地污染,其它地区尚未污染或污染较轻。并提出五点防止地下水污染的对策性意见。 相似文献
13.
Groundwater resources assessment of the Koyna River basin,India 总被引：2，自引：1，他引：1
The Western Ghats (hills) region of the Indian peninsula in western India receives heavy precipitation (4,000–6,000 mm/year), but the headwater basins that coalesce runoff from these hills retain very small quantities of water due to the steep topography. However, the narrow valleys in these hills support agriculture based on surface water irrigation, and several medium to large irrigation projects have already been constructed with well-defined canal networks. These developments have boosted agricultural productivity in the region, but at the same time they are causing an economic disparity between the command areas (irrigated by these canals) and non-command areas. Water-logging problems are also occurring in low-lying areas. While these problems are mainly due to poor groundwater management strategies in the region, the groundwater resources in these headwater basins should be properly assessed and suitable measures taken for uniform groundwater development. As a first step in this direction, groundwater resources have been assessed as a case study for the lower Koyna River basin, a head water basin on the east of the main ridge of the Western Ghats.Regional specific yield (0.012) and groundwater recharge have been estimated on the basis of water table fluctuation method. Groundwater recharge amounting to 57 MCM (million m3) in a year takes place in the region through vertical percolation of rainwater (31 MCM), return flow of water applied for irrigation (23 MCM), and recharge due to surface water tanks (3 MCM). Recharge to deeper aquifers has been estimated at 1 MCM during dry seasons (November–May). Safe yield has been estimated at 58 MCM annually which includes the present groundwater draft by wells for domestic, stock, and irrigational needs estimated at 16.50 MCM per year and the natural losses from the groundwater system which are mostly baseflow and spring discharges amounting to 38 MCM (35 MCM baseflow + 3 MCM spring flow) per year, out of which 7 MCM is already being directly pumped from the tributaries of the Koyna River for irrigational needs. Thus, there remains a balance of only 3.5 MCM of groundwater for further groundwater development. Assuming that at least 25% (7 MCM) of the unutilized baseflow (28 MCM) can be brought to fruitful use, about 10.5 MCM (7+3.5 MCM) of groundwater can be used in the existing hydrogeological environment through about 500 additional wells.
相似文献
Resumen La región de las montañas de Western Ghats, al Oeste de la Península India, registra elevados valores de precipitación (de 4.000 a 6.000 mm/a), pero las condiciones topográficas de dichas montañas no permiten la existencia de acuíferos de entidad suficiente para albergar volúmenes grandes de aguas subterráneas. Los valles estrechos de las montañas sí permiten el desarrollo de las aguas superficiales, de manea que se ha realizado varios proyectos medianos y grandes de riego mediante redes de canales bien definidas. Estos desarrollos han propiciado un aumento de la producción agrícola en la región, pero, a la vez, se ha agudizado las diferencias económicas entre las zonas regadas y las no regadas. Además, las depresiones topográficas están padeciendo problemas de inundación. Como estos problemas son principalmente debidos a estrategias deficientes de gestión de las aguas subterráneas, se recomienda que los recursos subterráneas de las cuencas de cabecera sean adecuadamente determinados, y que se adopte medidas apropiadas para desarrollarlos uniformemente. El primer paso ha consistido en determinar los recursos subterráneos de la cabecera del río Koynam, situada al Este de la Sierra principal de los Western Ghats. Se ha estimado todos los parámetros de recarga y descarga, así como los recursos renovables, en la cuenca del río Koyna ubicada aguas debajo de la presa de Koyna.
Résumé La région des Collines occidentales (Western Ghats) de la péninsule indienne en Inde occidentale reçoit de fortes précipitations (4.000–6.000 mm/an); mais les bassins situés en tête qui convergent dans ces collines retiennent très peu d'eaux souterraines du fait des mauvaises conditions de pente en surface. Les vallées étroites dans ces collines offrent de larges espaces pour la mise en valeur des eaux de surface, en sorte que plusieurs projets d'irrigation moyens ou importants ont déjà été réalisés dans ces régions avec un réseau bien défini de canaux. Cette mise en valeur a réellement poussé la productivité agricole de la région, mais en même temps elle produit aussi une disparité économique entre les régions desservies (zones irriguées par ces canaux) et non desservies. Des problèmes relatifs à l'eau se posent également dans les zones basses. Alors que ces problèmes sont surtout dus à de médiocres stratégies de gestion dans la région, il est recommandé que les ressources en eaux souterraines dans ces bassins en tête soient correctement évaluées et que des mesures adéquates soient prises en vue d'une mise en valeur uniforme des eaux souterraines. À titre de première étape dans cette direction, les ressources en eaux souterraines ont été évaluées lors d'une étude de cas du bassin de la rivière Koyna, un bassin de tête situé à l'est de la chaîne principale des Collines Occidentales. Tous les paramètres d'entrée et de sortie ont été estimés et un bilan a été réalisé entre ces deux composantes. Les ressources statiques et dynamiques en eaux souterraines ont été estimées et un rendement sûr a été déterminé pour le bassin de la rivière Koyna en aval du barrage de Koyna.
相似文献
14.
Lack of appropriate hydrogeological base maps, poor knowledge of the geology of the Nigerian terrain, lack of infrastructural
facilities and absence of a working legislature beset the practice of hydrogeology causing problems in exploration, exploitation,
operation, control and management of the abundant groundwater resources of Nigeria.
This study shows that Nigeria has about 224 trillion l/year of surface water and about 50 million trillion l/year of groundwater
for a population of about 128 million. Domestic consumption need was about 6.0 billion l/year in 2001, indicating that there
is an abundant water resource potential.
A hydrostratigraphic basin delineation is attempted with ten hydrogeological basins as hydrogeological units, which bring
to light the intrinsic causes and solutions to the problems of borehole failures, dam collapses, brine-salt water intrusions,
and insufficient water delivery to millions of Nigerians.
Electronic Publication 相似文献
15.
Glen R. Walker Lu Zhang Tim W. Ellis Tom J. Hatton Cuan Petheram 《Hydrogeology Journal》2002,10(1):68-90
To manage dryland salinity, one needs to know how changed land use affects groundwater recharge. Few techniques are available
for comparing 'deep drainage' under different land uses. Soil-tracer methods, although good for replication and remote field
sites, are subject to spatial variability. Lysimeters are good for comparisons but are difficult for drier areas and sloping
land. Agronomic water-balance studies, where appropriate soil-water measurements exist, may be used with a soil-vegetation
model to estimate long-term deep drainage. Complex models are required to analyze specific land-use differences, such as perenniality
and root and leaf area dynamics, but models require intensive and extensive data for calibration. This approach is time-consuming,
labour-intensive, and difficult in remote locations. Because of the one-dimensionality of most soil-vegetation models and
the small fraction of the total water balance that is deep drainage, little success has occurred in extrapolating beyond the
research plot, or to spatially heterogeneous systems such as alley farming. Some 'top-down' modelling and landscape disaggregation
approaches have been partially successful in making catchment or regional-scale predictions. The direction for further work
depends on the level of recharge reduction that is required for most groundwater systems and difficulties that it imposes.
Electronic Publication 相似文献
16.
Groundwater recharge: an overview of processes and challenges 总被引：11，自引：13，他引：11
Since the mid-1980s, a relative explosion of groundwater-recharge studies has been reported in the literature. It is therefore
relevant to assess what is now known and to offer further guidance to practitioners involved in water-resource development.
The paper summarizes current understanding of recharge processes, identifies recurring recharge-evaluation problems, and reports
on some recent advances in estimation techniques. Emphasis is accorded to (semi-)arid regions because the need for information
is greatest in those areas – groundwater is often the only water source, is vulnerable to contamination, and is prone to depletion.
Few studies deal explicitly with groundwater recharge in temperate and humid zones, because recharge is normally included
in regional groundwater investigations as one component of the water balance. The resolution of regional water-balance studies
in (semi-)arid areas is, in contrast, often too low to quantify the limited recharge component with sufficient precision.
Despite the numerous studies, determination of recharge fluxes in (semi-)arid regions remains fraught with uncertainty. Multiple
tracer approaches probably offer the best potential for reliable results in local studies that require 'at-point' information.
However, many investigations indicate that these approaches are not straightforward, because in some cases preferential flow
contributes as much as 90% of the estimated total recharge. Tracer results (e.g. Cl–, 3H) must therefore be interpreted with care in areas with multi-modal flow in the vadose zone. Moreover, accurate estimation
of total chloride deposition is essential, and tritium may be influenced by vapour transport at low flux rates. In addition,
paleoclimatic and paleohydrological conditions may cause discrepancies between measured actual processes and calculated long-term
averages.
The frequently studied issues of localized recharge and spatial variability need not be a problem if concern is with regional estimates. The key for practitioners is
the project objective, which dictates whether 'at-point' or area-/groundwater-based estimation methods are appropriate. Many
indirect (wadi) recharge studies reported in the literature are site specific; the relationship between 'at point' hydraulic properties
and channel-reach losses demands further investigation.
Electronic Publication 相似文献
17.
为探讨冲洪积平原地带地下水水质劣变机理及过程,开展了不同的水土样品组合的16组淋滤试验,以期揭示不同源水在土柱入渗过程阴阳离子、硬度和TDS的变化规律以及地下水类型的演化特征。试验结果表明:淋出液中,阴离子浓度的变幅由大到小依次为HCO_3~-、NO_3~-、SO_4~(2-)、Cl~-和F~-,阳离子的变幅则依次为Na~++K~+、Ca~(2+)和Mg~(2+)。淋出液的硬度、TDS和水化学类型均呈现出有规律的变化,先期主要受控于源水,尔后则主要受土柱介质的影响。除了以垃圾作为淋滤介质的试验外,其他组合的试验都出现了初期TDS和硬度升高的过程,之后与源水趋于一致,揭示了淋滤中浸泡—水岩相互作用—吸附解析—淋洗等复杂过程。 相似文献
18.
Groundwater abstraction has resulted in spring flow and groundwater base-flow declines in the Hillsborough River system of central Florida, USA. These declines have resulted in reduction of inflows to the Tampa city reservoir as well as likely adverse environmental effects on riverine and estuarine biota. Causes evaluated for the declines include effects of groundwater development, reduced rainfall, and land alterations. The karstic, heterogeneic nature of the area renders groundwater flow modeling an ineffective method for overall evaluation. Therefore, the evaluation of these declines is accomplished through the systematic use of parametric and nonparametric statistical techniques. These techniques include contingency table analysis, linear regression, Kendall-Theil and Mann-Kendall trend analysis, locally weighted regression, Pearson correlation, Kendall-tau correlation, Spearman correlation, runs test, Student’s t test, and the Kruskall-Wallis test. Data evaluated include groundwater withdrawals, rainfall, base flow, streamflow, stream stage, spring flow, and groundwater levels. Additional methods used include double mass analysis, base flow separation, a low-stage trend analysis, data visualization techniques, and water level change maps. The methodical application of these analyses and techniques to the hydrologic and climatic data yields the conclusion that the primary factor causing the spring flow and base-flow declines is lowered groundwater levels caused by over-abstraction. 相似文献
19.
20.
Assessment of water level threshold for groundwater restoration and over-exploitation remediation the Beijing-Tianjin-Hebei Plain 
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下载免费PDF全文 Yang Hui-feng Meng Rui-fang Bao Xi-lin Cao Wen-geng Li Ze-yan Xu Bu-yun 《地下水科学与工程》2022,10(2):113-127
The Beijing-Tianjin-Hebei Plain (BTHP) is the political, economic and cultural center of China, where groundwater is the main source of water supply to support social and economic development. Continuous overdraft of the resources has caused a persistent decline of groundwater level and formed a huge cone of depression at a regional scale. This paper addresses current groundwater situation over the BTHP area. The paper also delineates the groundwater flow field, using groundwater level data, in order to provide an effective method for the restoration of groundwater level and associated water resources management. Based on the analysis of multiple factors, such as groundwater level, soil salinization, ground subsidence, groundwater recharge and storage, urban underground space security, formation of fractures, and seawater intrusion, the threshold for groundwater level restoration is defined, and some measures for groundwater over-exploitation management are accordingly proposed. The study shows that: (i) Since the 1980s to 2020, shallow groundwater level in the western part of the BTHP area has dropped by 25 m to 60 m, while the cumulative decline of deep groundwater in the central and eastern regions is in the range of 40–80 m; (ii) The water table of the shallow groundwater within the depression zone over the Western Piedmont Plain should be controlled in the range of 15–30 m below ground level (mbgl), while the depth of groundwater level in large and medium-sized urban areas should be controlled within 20–30 mbgl. The groundwater level in the resource preservation area should be controlled within 10–15 mbgl, and the groundwater level in the area with identified soil salinization in the central and eastern plain should be controlled within 3–10 mbgl. However, for the deep groundwater in the central and eastern plainwater, the main focus of the resources management is to control the land subsidence. The water level in the severe land subsidence area should be controlled within 45–60 mbgl, and in the general subsidence area should be controlled within 30–45 mbgl; (iii) Based on the water level recovery threshold and proposed groundwater overdraft management program, if the balance of abstraction and recharge is reached in 2025, the shallow groundwater abstraction needs to be gradually reduced by about 2×108 m3. Meanwhile, the ecological water replenishment of rivers through the South-to-North Water Transfer Project should be increased to 28.58×108 m3/a, and the deep groundwater abstraction needs to be gradually reduced by 2.24×108 m3. To reach the target of shallow groundwater level in 2040, surface water replacement is recommended with a rate of 25.77×108 m3/a and the ecological water replenishment of rivers in the South-to-North Water Diversion Project should reach 33.51×108 m3/a. For deep groundwater recovery, it is recommended to replace the deep freshwater extraction with the utilization of shallow salt water by 2.82×108 m3 , in addition to the amount of 7.86×108 m3 by water diversion. The results are of great significance to the remediation of groundwater over-exploitation, the regulation of water resources development and utilization, and ecological protection in Beijing-Tianjin-Hebei plain. 相似文献