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地下水弥散系数的野外试验新方法 总被引:5,自引:1,他引:4
弥散系数是地下水污染数学模型的基本参数.本文提出一种获得纵向和横向弥散度的野外试验新方法.该法能很好地控制野外试验的水位和流场形态,提高地下水坡降,且方便可行.同时还介绍一种与配线法不同的,用联立方程迭代求解的弥散度新算法。 相似文献
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Vahid Gholami Zabihollah Yousefi Hosseinali Zabardast Rostami 《Water Resources Management》2010,24(7):1415-1424
Water salinity is one of the main restrictive factors in water exploiting. Also, unsuitable management and exploitation of
water resources has led to an increase of surface and groundwater salinity. Thus, in view of human needs to water resources,
it is necessary to study and define water salinity factors in order to weaken these factors. This research has been conducted
to investigate the factors of groundwater salinity and also, to provide a model for estimating groundwater salinity on the
Caspian southern coasts. Data included in the model are: water qualitative examinations in the area, annual precipitation
and evaporation, water table depth, surface water salinity, aquifer formation (Transmissivity) and distance from Caspian Sea.
Surface and groundwater salinity was estimated by sampling in different sites on the Caspian southern coasts. Then, Multivariate
Regression method was used by using SPSS software. In this stage, groundwater EC has been used as a variable for water salinity
or dependent variable and groundwater salinity factors have been used as independent variables. A linear model and a non-linear
model were presented. The models efficiency was evaluated by applying them in the sites that their data were not used for
presenting the models. Finally, groundwater EC average map was provided by using the presented non-linear model and Geographic
Information System in the Eastern part of Mazandaran province. In view of salinity hazard increases in the coastal terrains
and agricultural areas, the places with high hazard salinity must be defined and managed to decrease water resources salinity. 相似文献
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物元分析方法在地下水质量综合评判中的应用 总被引:6,自引:1,他引:5
鉴于目前地下水质量评判方法中存在人为影响因素过多、权值计算的不确定性等不足,提出了一种基于物元分析理论的新评判方法,采用地下水质量综合评判的各种指标,根据计算出的综合关联度,实现对地下水质量等级的综合评判。实例表明该方法是可靠的,在地下水质量评判领域具有进一步的研究与应用价值。 相似文献
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A method is presented for estimating the annual groundwater withdrawal based on water balance resulting from surface and groundwater
hydrological considerations. The unknown groundwater losses of the aquifer are estimated from the groundwater level fluctuations,
the specific yield and the groundwater withdrawal prior to the installation of the irrigation network. The meteorological
and hydrometric data are used in the Sacramento hydrological conceptual model for the estimation of the stored groundwater
volume, via minimization of the difference between the simulated and measured stream discharge. Following the installation
of the network due to poorly kept field records, an initial estimation of the groundwater withdrawal is made based on the
fluctuations of the groundwater level, the specific yield, and the annual precipitation. The monthly stored groundwater volume
is verified against the volume obtained during the recharge of the basin (November–April). The difference between the groundwater
volume and the measured discharge of the basin (May–October) is in agreement with the initial estimation of the groundwater
withdrawal. This method is applied successfully in an agricultural basin on the island of Crete, Greece and its novelty lies
in the fact that it can be used in basins where groundwater withdrawal is not known or data is incomplete. 相似文献
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Groundwater studies in several African countries show that the contamination of water-supply aquifers is mainly due to improper
placement of land-based activities such as agriculture, industries, waste disposal. In South Africa, groundwater pollution
is also of increasing concern due to fast population growth and accompanying development. Groundwater protection zoning is
a supplemental methodology for groundwater management that incorporates land use planning. The land is managed to minimize
the potential of groundwater contamination by human activities that occur on or below the land surface. The various benefits
associated with implementation of protection zoning are discussed for stakeholders such as communities, water supply companies,
ecosystems and policy makers. A South African case study is presented comparing the cost of protection with the cost incurred
due to the treatment of sick and dying people due to contaminated drinking water. These benefits must be communicated to the
stakeholders to start the implementation at all management levels. Implementation steps of groundwater protection zones are
discussed and can be tested even with low budgets and little data available. Monitoring and reassessment of protection zones
are important to test the effectiveness and prove to decision makers that the money was well spent. The legal framework for
implementation of groundwater protection zoning in a South African context is described, where the water law makes provision
for tools like differentiated protection, licensing and recovery of cost. Challenges regarding implementation of groundwater
protection are discussed with some action steps on how to move forward. 相似文献
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Duan Xiang-bao 《水动力学研究与进展(B辑)》1996,(4)
NUMERICALMODELINGANDOPTIMALESTIMATIONOFTHETRANSPORTOFGROUNDWATERPOLLUTIONDuanXiang-bao(NamingHydraulicResearchInstitute,Namin... 相似文献
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本文基于剖开算子法,提出耦合求解地下水流方程和污染运移方程的数值方法,并Kalman滤波技术在地下水污染研究中的应用。计算例表明,本文所提数值方法及Kalman滤波理论的应用,能够避免数值模拟过程中的不良现象,大大提高计算精度,更好地应用于实际工程。 相似文献
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The primary network of groundwater level observation wells aims at realizing a regional groundwater management policy. It may give a regional picture of groundwater level with emphasis on the natural situation. Observation data from the primary network can be used to estimate the actual state of groundwater system. Since the cost of the installation and maintenance of a groundwater monitoring network is extremely high, the assessment of effectiveness of the network becomes very necessary. Groundwater level monitoring networks are the examples of discontinuous sampling on variables presenting spatial continuity and highly skewed frequency distributions. Anywhere in the aquifer, ordinary kriging provides estimates of the variable sampled and a standard error of the estimate. In this article, the average Kriging standard deviation was used as a criterion for the determination of network density,and the GIS-based approach was analysized. A case study of groundwater level network simulation in the Chaiwopu Basin, Xinjiang Uygur Autonomous Region, China, was presented. In the case study, the initial phreatic water observation wells were 18, a comparison of the three variogram parameters of the three defferent variogram models shows that the Gaussian model is the best. Finally, a network with 55 wells was constructed. 相似文献
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地理信息系统(GIS)是水文地质研究的一个重要工具,地理信息系统在水文地质领域的应用是水文地质研究的热点之一。在总结近年来国内外大量相关研究成果的基础上,从基于GIS的地下水资源评价、地下水资源管理、地面沉降、地下水水质评价及污染物分析、水文地质调查、地下水保护,以及GIS与数值模拟技术的结合等方面介绍了地理信息系统在水文地质领域的最新应用,提出了GIS在水文地质领域应用存在的问题,并对今后GIS在水文地质领域的应用进行了展望。指出,今后应加强GIS与地下水模型及分布式水文模型的集成、基于GIS的地下水系统仿真三维或四维可视化、网络GIS技术的应用,以及流域水资源综合管理评价系统的建立等方面的研究。 相似文献
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Simulation-Optimization Modelling for Sustainable Groundwater Management in a Coastal Basin of Orissa, India 总被引:6,自引:5,他引:1
The Balasore coastal groundwater basin of Orissa in eastern India is under a serious threat of overdraft and seawater intrusion.
Two optimization models were developed in this study for the efficient utilization of water resources in Balasore basin during
non-monsoon periods: (a) a non-linear hydraulic management model for optimal pumpage, and (b) a linear optimization model
for optimal cropping pattern in integration with a calibrated and validated groundwater flow simulation model. Based on the
simulation-optimization modeling results, optimal pumping schedules, cropping patterns, and corresponding groundwater conditions
are presented for three scenarios viz., wet, normal and dry years. It was found that optimal pumping schedules and corresponding
cropping patterns differed significantly under the three scenarios, and the groundwater levels improved significantly under
the optimal hydraulic conditions compared to the existing condition. In dry years, the groundwater levels under the present
pumping pattern and the optimal pumpage indicated that the non-monsoon pumpage should not exceed the optimal pumpage in the
absence of remedial measures in the basin. It is concluded that in order to ensure sustainable groundwater utilization in
the basin, the optimal cropping pattern and pumping schedule should be adopted by the farmers. 相似文献
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A simple management model for irregularly located wells is presented by considering interference between adjacent wells at a certain risk level and safe groundwater velocity which depends mainly on the hydraulic conductivity at individual well sites. The final decision variables for a confined aquifer are the maximum allowable discharge, velocity, and drawdown quantities. Regional variations of these quantities are presented in the form of maps which are most useful tools for identifying mismanagement areas and, accordingly, the necessary precautions can be taken. The application of the management model is performed with the actual field data from the Saq formation in the north-western part of the Kingdom of Saudi Arabia. 相似文献
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应用门限自回归 (TRA)模型解决具有周期性变化和下降趋势的地下水位的预测问题 ,可以有效地利用地下水位资料所隐含的时序分段相关性 ,起到限制模型误差 ,保证模型预测性能的稳定性 ,提高预测精度的作用 相似文献
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CHENJia-jun TIANKai-ming GUOQiao-yu 《水动力学研究与进展(B辑)》2005,17(2):154-163
When water resource or quality problems assoelated with phreatic water in geological settings are studied,information about water table elevations is often crucial. In those eases where the water table is a subdued replica of the ground surface, universal cokriging can be used to estimate water table elevations at un sampled locations on the basis of water table and ground surface elevation measurements obrained at well locations. In this paper, universal cokriging,with ground surface elevation considered as a co variate, was used to estimate water table elevations. Universal cokriging equations were derived, an iterative method for obtaining experimental variograms was established, and a ease study of an initial groundwater flow simulation in the Xiuwu County,Henan Province, China, was presented. In the ease study,the initial groundwater flow regime was represented both by universal cokriging with the ground surface elevation serving as a covariate and by universal kriging without the inclusion of ground surface elevation as a covariate. A comparison of the results from these two approaches shows that groundwater levels of phreatic water at locations without measurements in regions with unconsolidated porous media can be estimated more accurately by universal cokriging. 相似文献
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Optimal Locations of Groundwater Extractions in Coastal Aquifers 总被引:1,自引:0,他引:1
A regional water supply management model for coastal aquifers was developed. One of its outcomes is the definition of the
optimized locations for groundwater withdrawal. Such a tool permits the analysis of alternative plans for groundwater extraction
and the sustainable use of water resources in a coastal aquifer subject to saltwater intrusion. The principal components are
the evolutionary optimization and the analytical/numerical simulation models. The optimization technique looks for the best
well locations taking into consideration the economic results and the satisfaction of the societal water demand. However these
two concerns are conditioned by trying to control the saltwater intrusion, i.e., preserving the environmental equilibrium.
The simulation model uses the governing mathematical equations for groundwater movement to find the interface between freshwater
and saltwater. Because of the non-linearity in the system and the possibility of a jumping interface, a security distance
was defined. This is a controlling variable which can be set by the decision makers. The model was applied to a typical case
with interesting results. For example, diagrams showing the relationship between the location of the wells and the security
distance(s) are of importance to the managers. It was also crucial to have an understanding of the tradeoffs between groundwater
withdrawals, positions of the wells from the coast line, and the security distance. The model was also applied to a real case
in order to relate the extractions, distances and artificial recharge (not presented in this paper). 相似文献
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In this study, a management model is presented for planning groundwater development in costal deltas with paleo channels. It is demonstrated that paleo channels are the best locations for locating the wells for large-scale
pumping. Groundwater flow in these aquifers is simulated using a three-dimensional (3-D) density-dependent flow and transport
model SEAWAT, which is suitable for a coastal and deltaic environment. A simulation-optimization model is used to determine
the optimal locations and pumpages for groundwater development for a group of production wells, while limiting the salinity
below desired levels. The mixed integer problem is solved using the Simulated Annealing algorithm and the SEAWAT simulation
model. A trained Artificial Neural Network (ANN) is used as the virtual SEAWAT model to perform the simulations, in order
to reduce the computational burden for application of the model on desktop computers. The applicability of the model is demonstrated
on a hypothetical, but near-real, delta system. 相似文献
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河南省主要城市地下水超采区评价 总被引:6,自引:0,他引:6
在分析近期地下水观测、调查资料成果的基础上,描述了城市区域水文地质特性,并对17座主要城市不同含水层的年均地下水补给量、可开采量和实际开采量进行了计算评价。按照地下水超采区评价方法,划分出26处地下水超采区;提出了超采区地下水开发利用和管理的建议。 相似文献