共查询到20条相似文献，搜索用时 86 毫秒
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在分析大区域地下水流数值模型构建缘起的前提下,系统论述了近年来地下水流数值模拟在大区域地下水资源评价、水文地质参数确定、地面沉降、溶质运移、海水入侵、盐渍化、风险评估、地下水管理及地表水与地下水的联合开发利用等方面的国内外研究应用现状;归纳、总结了目前大区域地下水流数值模型在灵敏度分析、裂隙和岩溶介质中模型建立、基于地下水流数值模拟的溶质运移模型建立、地下水流数值模型构建所需工作量等理论和方法研究及实际建模过程中存在的一些问题;展望了今后大区域地下水流数值拟在研究范围、模拟技术与方法以及与其它模型耦合等方面的发展趋势。 相似文献
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地下水流系统理论与研究方法的发展 总被引：6，自引：0，他引：6
地下水流系统理论的提出,推动了现代水文地质学的发展。以Tóth经典地下水流系统理论建立方法为基础,综述了基于Tóth方法的地下水流系统的模拟成果,分析了Tóth方法得出的水流模式与控制因素的关系,以及地下水流系统理论从概念到实际应用的发展。同时,对中国地质大学(武汉)提出的地下水流系统通量上边界模拟方法也进行了系统论述,在物理模拟实验与数值模拟基础上,认为通量上边界分析方法是对Tóth方法的改进与完善,有利于对地下水流系统发育的物理机制理解;该方法能够更全面认识地下水流系统模式及其转化,定量出各影响因素对地下水流模式的控制关系。最后指出地下水流系统理论是当代水文地质学的核心概念框架,应该重视地下水流系统理论物理机制和数学模拟方法的研究,加强新技术方法的引入,拓宽其应用领域的研究等。 相似文献
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当前世界面临着越来越严重的水资源缺乏等环境压力,大尺度区域地下水资源与环境问题日益得到重视。在区域地下水流理论创立、应用与发展50年之际,由中国地质调查局和国际水文地质学家协会区域地下水流专业委员会主办,西安地质调查中心和中国地质大学(北京、武汉)等单位承办了区域地下水流理论、应用与发展国际学术研讨会。区域地下水流理论创始人Tóth教授以及来自13个国家的160多位水文地质专家从地下水流理论方法、实践应用等方面进行研讨和交流,将对区域地下水流理论的研究起到积极的促进作用,有力推动该理论的进一步发展和实际应用。笔者系统分析梳理了与会者的报告,归纳总结了国际区域地下水流理论研究进展和发展动态,以期为区域地下水流理论更加广泛地应用于水文地质环境地质相关研究领域提供参考。 相似文献
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岛屿是我国领土的重要组成部分,对国家安全和国防军事意义非凡。岛屿的地下水资源尤为珍贵,地下水流场模拟是研究地下水分布规律的重要手段。水文地质条件复杂、可利用的观测井较少等原因,造成了基岩岛屿水文地质模型概化精度不高、初始条件难以获取等问题。为克服基岩岛屿地下水流场模拟的诸多困难,将珠海外伶仃岛作为研究区,利用数字高程模型数据开展地质地貌建模; 利用探地雷达法、直流电法与地质分析对岛屿进行探测,获取了地层数据; 采用地下水遥感评估法,利用实测井位数据,确定了地下水的初始水位,进而对基岩岛屿地下水流场进行建模; 最终,通过对外伶仃岛地下水流场的数值模拟得出地下水模拟流场图。岛上多个测点的探测水位值与模拟水位相关性较好,其拟合优度R2为0.872 2。由此可见,综合遥感、物探、水文地质手段等技术方法获取的数据,采用地下水模拟软件或程序实现基岩岛屿地下水流场的数值模拟,是基岩岛屿地下水资源研究的一个有效方法。 相似文献
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新疆孔雀河灌区面临地下水超采问题,科学认识区域地下水流系统的发育条件和演变特征,是优化地下水资源开发利用方式的基础.通过构建第四系含水层三维地下水稳定流模型,利用流线追踪技术,模拟识别了孔雀河流域19702020年期间地下水流系统的变化特征.结果 表明,不同补给区和排泄区通过流线进行组合,在孔雀河周边形成了交错分布的地下水流系统,其空间分布格局随灌区地下水开采规模而变化.在20世纪70年代的拟天然状态,灌区主要发育自北向南的地下水流系统,其空间分布格局取决于水文地质参数和排泄要素,并可能存在1～4个以孔雀河为排泄带的流动系统.在有强烈地下水开采的现状条件下,灌区地下水流系统转变为从四周流向漏斗中心,截断了从孔雀河上游渗漏到中下游河道排泄的水流系统.近50 a来,以潜水蒸发为排泄方式的地下水流系统投影面积萎缩了29％,而以地下水开采为排泄方式的地下水流系统投影面积从零增加到研究区面积的40％.潜水蒸发对自然生态系统具有重要的支撑作用,灌区地下水开采应有所控制以保障潜水蒸发型地下水流系统的发育条件. 相似文献
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水资源短缺的鄂尔多斯盆地内地下水遭受硝酸盐(NO3-)污染等问题日益突出,识别盆地不同地下水流系统的NO3-分布规律及其成因,对地下水资源的合理利用与保护具有重要意义.选取鄂尔多斯盆地北部湖泊集中区白垩系地下水系统为研究对象,基于水化学和聚类 主成分分析划分地下水流系统级次,在此基础上对比分析不同级次地下水流系统中NO3-分布特征,综合水化学和环境同位素分析识别多级次地下水流系统中NO3-来源及其潜在过程.研究表明:研究区ρ(NO3)超出地下水质量标准(GB/T 14848-2017)Ⅲ类水标准的地下水样品集中在局部-中间地下水流系统,其超标率达到28％;区域地下水流系统中ρ(NO3)均值约为1 mg/L.研究区不同级次地下水流系统中ρ(NO3-)分布特征主要与人类活动影响程度有关,而地下水蒸发富集和反硝化衰减作用对ρ(NO3-)的影响可以忽略.其中,局部-中间地下水流系统受到人类活动产生的污染影响显著,其NO3-污染主要来源于无机铵肥和粪便污水等;区域地下水流系统可能尚未受到人类活动污染,其NO3-来源于天然有机氮矿化. 相似文献
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河北平原地下水在经过长期开发利用后,出现了一系列环境问题,地下水的流动模式以及均衡状态发生了很大改变。从地下水年龄结构出发,利用MODFLOW-2000建立稳定流模型对地下水流数值进行模拟,对河北平原的地下水年龄结构以及地下水流场特征进行研究分析,重点研究了地下水储存量的变化过程以及影响因素,并通过非饱和带水流模型、土壤水均衡模型以及地下水流模型三模型相耦合的方式,对河北平原饱和带储存量变化、地下水补给量以及非饱和带中地下水滞留时间进行了估算。模拟结果显示:河北平原1975~2015年间浅层含水层地下水储存量减小速率约为30 mm/yr,减少量约占总储量的15%,说明地下水存储量的减少主要是由于浅层地下水存储量的减少引起;根据模型修正结果计算,河北平原年地下水补给量为120 mm,灌溉和降水补给为100 mm,渗流以及山前侧向补给为20 mm,降水量的变化趋势与地下水补给趋势保持一致,相关系数为0.92,地下水补给有25%来自降水和灌溉;地下水年龄差异与模拟参数存在变量关系,弥散度越大,地下水年龄差异越大。该模拟研究成果为今后地下水系统的研究提供数值依据。 相似文献
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Haiyang Xi Qi Feng Wei Liu JianHua Si Zongqiang Chang Yonghong Su 《Environmental Earth Sciences》2010,60(5):953-963
Water resources is a primary controlling factor for economical development and ecological environmental protection in the
inland river basins of arid western China. Groundwater, as the important component of total water resources, plays a dominant
role in the development of western China. In recent years, with the utilization ratio of surface water raised, the groundwater
recharge rate has been reduced by surface water, and groundwater was exploited on a large-scale. This has led to the decline
of groundwater levels and the degradation of eco-environments in the lower reaches of Heihe watershed, especially. Therefore,
the study on the groundwater-level change in recent years, as well as simulating and predicting groundwater levels changes
in the future is very significant to improve the ecological environment of the Heihe River Basin, coordinate the water contradiction,
and allocate the water resources. The purpose of this study is to analyze the groundwater-level variations of the Ejina region
basin on a large-scale, to develop and evaluate a conceptual groundwater model in Ejina Basin; according to the experimental
observation data, to establish the groundwater flow model combining MODFLOW and GIS Software; simulated the regional hydrologic
regime in recent 10 years and compared with various delivery scenarios from midstream; determined which one would be the best
plan for maintaining and recovering the groundwater levels and increasing the area of Ejina Oasis. Finally, this paper discusses
the possible vegetation changes of Ejina Basin in the future. 相似文献
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长春市地下水动态研究 总被引：4，自引：2，他引：2
根据长春市地下水观测井的动态监测资料,分析了长春市主要地下水类型的动态变化规律及原因。2000年以后,地下水位处于回升状态,松散岩类孔隙水水位埋深值年均减少0.16m,基岩裂隙水年均减少0.78m,其主要原因为限制开采量。典型观测孔水位埋深变化趋势公式表明,浅层地下水水位与气温密切相关,但滞后于气温1～1.5个月。 相似文献
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Patterns in groundwater chemistry resulting from groundwater flow 总被引：18，自引：7，他引：11
Pieter J. Stuyfzand 《Hydrogeology Journal》1999,7(1):15-27
Groundwater flow influences hydrochemical patterns because flow reduces mixing by diffusion, carries the chemical imprints
of biological and anthropogenic changes in the recharge area, and leaches the aquifer system. Global patterns are mainly dictated
by differences in the flux of meteoric water passing through the subsoil. Within individual hydrosomes (water bodies with
a specific origin), the following prograde evolution lines (facies sequence) normally develop in the direction of groundwater
flow: from strong to no fluctuations in water quality, from polluted to unpolluted, from acidic to basic, from oxic to anoxic–methanogenic,
from no to significant base exchange, and from fresh to brackish. This is demonstrated for fresh coastal-dune groundwater
in the Netherlands. In this hydrosome, the leaching of calcium carbonate as much as 15 m and of adsorbed marine cations (Na+, K+, and Mg2+) as much as 2500 m in the flow direction is shown to correspond with about 5000 yr of flushing since the beach barrier with
dunes developed. Recharge focus areas in the dunes are evidenced by groundwater displaying a lower prograde quality evolution
than the surrounding dune groundwater. Artificially recharged Rhine River water in the dunes provides distinct hydrochemical
patterns, which display groundwater flow, mixing, and groundwater ages.
Received, May 1998 · Revised, August 1998 · Accepted, October 1998 相似文献
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Geomorphic aspects of groundwater flow 总被引：3，自引：0，他引：3
Robert G. LaFleur 《Hydrogeology Journal》1999,7(1):78-93
The many roles that groundwater plays in landscape evolution are becoming more widely appreciated. In this overview, three
major categories of groundwater processes and resulting landforms are considered: (1) Dissolution creates various karst geometries,
mainly in carbonate rocks, in response to conditions of recharge, geologic setting, lithology, and groundwater circulation.
Denudation and cave formation rates can be estimated from kinetic and hydraulic parameters. (2) Groundwater weathering generates
regoliths of residual alteration products at weathering fronts, and subsequent exhumation exposes corestones, flared slopes,
balanced rocks, domed inselbergs, and etchplains of regional importance. Groundwater relocation of dissolved salts creates
duricrusts of various compositions, which become landforms. (3) Soil and rock erosion by groundwater processes include piping,
seepage erosion, and sapping, important agents in slope retreat and headward gully migration. Thresholds and limits are important
in many chemical and mechanical groundwater actions. A quantitative, morphometric approach to groundwater landforms and processes
is exemplified by selected studies in carbonate and clastic terrains of ancient and recent origins.
Received, May 1998 · Revised, September 1998 · Accepted, October 1998 相似文献
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Environmental tracers are used to estimate groundwater ages and travel times, but the strongly heterogeneous nature of many subsurface environments can cause mixing between waters of highly disparate ages, adding additional complexity to the age-estimation process. Mixing may be exacerbated by the presence of wells because long open intervals or long screens with openings at multiple depths can transport water and solutes rapidly over a large vertical distance. The effect of intraborehole flow on groundwater age was examined numerically using direct age transport simulation coupled with the Multi-Node Well Package of MODFLOW. Ages in a homogeneous, anisotropic aquifer reached a predevelopment steady state possessing strong depth dependence. A nonpumping multi-node well was then introduced in one of three locations within the system. In all three cases, vertical transport along the well resulted in substantial changes in age distributions within the system. After a pumping well was added near the nonpumping multi-node well, ages were further perturbed by a flow reversal in the nonpumping multi-node well. Results indicated that intraborehole flow can substantially alter groundwater ages, but the effects are highly dependent on local or regional flow conditions and may change with time. 相似文献
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基于GMS的岩溶山区三维地下水流模式识别 总被引：3，自引：1，他引：2
以高岚河东部多条支沟切割形成的连排型河间地块为研究区,基于1∶5万岩溶水文地质调查成果,利用GIS技术和径流分割,量化岩溶含水系统顶底板高程、获取入渗补给系数及地下水径流量等数据,运用三维地下水流数值模拟及粒子追踪地下水流线的方法,得出了研究区的地下水流模式。其结果表明:研究区地下水流模式主要受区域尺度的势源和势汇控制,局部的地形起伏对地下水位的影响不明显;支沟切割较深的凉伞沟、滩淤河流域,水流驱动力大,有利于局部水流系统的发育;随着东部补给高程的增加,流程逐渐增长,多发育局部水流系统,至山脊附近多发育排泄至高岚河的中间水流系统。当研究区年降雨量由中等的1 021.1 mm降为多年最低的725.5 mm时,由东部补给区排泄至高岚河的中间水流系统增加;在此降雨强度区间,不具备发育越过河间地块的中间或区域地下水流系统。 相似文献
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Influence of flooding on groundwater flow in central Cambodia 总被引：2，自引：1，他引：1
Cambodia is affected by flooding from the Mekong, Tonle Sap and Bassac rivers every year, which harms human populations and
damages property, as well as alters the water quality in aquifer systems. The objective of this paper is to highlight the
effects of river flooding on groundwater flow using numerical simulation. A two-dimensional groundwater flow model coupled
with a groundwater recharge model was applied to the research area in central Cambodia. River level variation was included
in model processes, and flood areas and periods were assigned. The results showed that during flooding periods, floodwater
from the three rivers played an important role in recharging groundwater. During the dry season, Tonle Sap River received
groundwater supply from the northwest, and levels in the Bassac and Mekong River dropped to lower than the groundwater level.
This study improves understanding of the surface water and groundwater flow system in the study area. 相似文献