李官堡水源地地下水流场数值模拟及预测

随着工业规模的发展,各城市都面临着地下水资源如何科学利用的难题,北方缺水城市沈阳李官堡水源地就面临着新增工业造成的用水压力,如何对该水源地的水资源进行科学评价是合理取用水的前提。在对模拟区范围、边界条件和孔隙水介质进行概化和对水文地质参数及其他参数确定的基础上,将该区域地下水流系统概化为均质、各向同性、二维、潜水非稳定地下水流系统,运用GMS模型软件对研究区的地下水流场进行了数值模拟预测。通过模型识别和可靠性分析认为,所率定的模型参数符合实际且模型边界条件合理;预测认为该区域地下水资源量不能满足新增企业用水量9.8万m3/d的需求。该评价方法不仅具有应用和推广价值,而且具有为地下水资源科学规划提供科学依据的重要作用。     

矿井涌水数值模拟及预测——以安徽省当涂县钟九铁矿为例

近年来伴随着矿井的开采,矿井涌水问题已成为矿井安全生产的首要问题,对于地质条件复杂的矿区,井下涌水量的科学预测是安全生产和合理取用水的前提。在对模拟区边界条件和孔隙水介质进行概化以及对水文地质参数和其他参数确定的基础上,将该区域地下水流系统概化为均质,各向同性,无侧限边界的三维非稳定地下水流系统,运用Visual MODFLOW软件对研究区的矿井涌水过程进行数值模拟及预测。通过模型模拟和可靠性分析认为,模型所率定的参数符合实际且模型边界条件合理,预测结果认为该区域井下涌水量能满足矿区采矿用水。     

陕西省吴堡县岔上水源地地下水允许开采量评价

根据陕西省吴堡县岔上水源地水文地质条件,确定了研究范围和边界条件,建立了研究区水文地质概念模型和地下水二维非稳定流数学模型,利用基于有限差分法的Visual MODFLOW进行地下水流数值模拟计算。经过模型的识别和验证,获取可靠的水文地质参数,然后对水源地地下水资源进行定量评价。通过对比设计了9种开采方案,选取了最为合理的开采方案,最终得到岔上水源地平枯期允许开采量均为6 880m3/d。根据模型预报结果,水源地目前的设计开采量是可行的。研究结果为研究区地下水资源的合理开发利用提供了依据。     

海河流域华北平原浅层地下水模型研究

由于对海河流域平原区地下水资源缺乏有效的管理,致使其严重超采,进而产生了一系列地质灾害,制约着经济社会的可持续发展.通过分析区域水文地质条件、含水层空间分布规律、水文地质参数、地下水流场、地下水观测资料等,概化研究区地质体,进而建立地下水模型,同时率定模型和标定大型漏斗.该模型首次全面认知和模拟了研究区地下水超采起始时间、超采量、漏斗发展过程,并预测了发展趋势.     

地下水流模型的建立——以华北平原为例

地下水流模型是辅助地下水资源量评价的一种工具,采用的建模方法主要是有限元法、有限差分法和边界元法。基于有限元法的地下水流模型包括地下水概念模型、数学模型、数值模拟模型3部分。概念模型建立包括含水层结构概化、研究区边界概化及水力特性确定3个步骤;数学模型和数值模拟模型建立包括数学方程式描述、区域剖分、定解条件处理、源汇项、水文地质参数确定、模型识别与检验及水量均衡分析7个步骤。以华北平原地下水流模型为例,阐述建模过程。     

松原市宁江区地下水资源开采综合评价

宁江区是松原市工农业生产发展的重点区域,为松原市各县区地下水开发利用程度较高的地区。本论文在系统分析该区地质、水文地质条件的基础上,建立了研究区的水文地质概念模型,利用三维地下水流模拟软件—Visual MODFLOW对该地区地下水的水位和水量进行模拟求解。利用识别的参数和验证后的模型评价研究区地下水资源,并提出近期承压水的合理开采量及开发利用建议。     

蒲州水源地地下水资源评价

本文在充分分析已获资料的前提下，对蒲州水源地地下水水质进行了评价，通过对水源地下水文地质条件的概化，建立了水源地地下水水流的数值模型．并利用有限单元法在计算机上实现了对水源地地下水资源的评价，提出了合理的地下水开采方案。     

蒲州水源地地下水资源评价

本文在充分分析已获资料的前提下，对蒲州水源地地下水水质进行了评价。通过水源地下水文地质条件的概化，建立了水源地地下水水流的数值模型，并利用有限单元法在计算机上同对水泊地地下水资源的评价，提出了合理的地下水开采方案。     

植被变化对地下水流系统影响模拟研究

针对鄂尔多斯高原存在的湖泊萎缩、地下水位下降等生态环境问题,采用数值模拟方法,通过建立区域尺度理想剖面二维地下水流模型,从水动力学机制上探讨了区域植被变化对地下水系统和湖泊的影响机制。通过对比目前常用的定水头边界与通量上边界条件两种方法的适用条件及不足,提出了改进后的变通量上边界概化方法,并将其应用于鄂尔多斯高原区域地下水模拟中。结果表明:区域植被条件改变对地下水和湖泊影响明显,该影响受区域地下水流系统演化规律的控制。     

青海省盐湖集团供水二期水源地数值模拟

针对山前冲洪积扇傍河水源地共有的水文地质条件,建立地下水流数学模型,采用Visual Modflow软件,选取极富水地段进行地下水数值模拟研究。在综合分析格尔木河冲洪积扇水文地质条件基础上,确定三维边界条件,建立水文地质条件概念模型及数学模型,通过对地下水梯度场、降速场与实测资料的识别与验证,模拟的流场形态与观测值及地下水动态拟合度较高,符合研究区水文地质条件。模型对10年内丰、平、枯水期降水频率下的开采方案结果及水均衡状态进行了预测,结果表明,拟建水源地所需的可开采水量(新增13.2万m3/d)基本可行。     

流域水资源配置方法研究

流域水资源配置解决的主要问题是确定不同天然来水情况下的省际规划出境水量,以及平原地下水规划开采量和入海水量.省际规划出境水量是流域水资源管理的基础指标,平原地下水规划开采量和入海水量是反映生态状况的指标.结合严重缺水的海河流域,研究并提出采用典型年法进行水资源配置的技术路线,提出2010规划水平年满足各项控制指标条件下省际配置分区经济社会发展的可利用水量.     

改进的WEAP模型在水资源管理中的应用

在水资源评价和规划模型(WEAP)的基础上耦合多边形网格地下水三维流有限差分模拟系统，建立了WEAP-Tsinghua模型。该模型既能反映各水文测站的径流情况和水资源供需关系与分配，也能反映地下水位动态变化。以石羊河流域为例，建立了该流域的水资源管理模型，并利用2000年用水结构、水文测站径流数据和地下水位观测数据进行参数率定和模型验证，模拟和实测地下水水头差值小于1.0m的观测孔达到总监测点数的50%，模拟和实测蔡旗同金川峡站流量年误差小于1％，模拟的用水结构符合实际，预测分析说明石羊河流域现状用水模式不合理。改进WEAP模型具有友好的用户界面和易于使用的功能，可用于区域水资源规划模拟分析。     

Stochastic Goal Programming Model for Optimal Blending of Desalinated Water with Groundwater

A stochastic goal programming (GP) model is developed in orderto determine the daily production of desalination plants to meet the requirements of water blending stations (WBS) for major cities in the Eastern Province of the Kingdom of SaudiArabia. The WBS is assumed to be a control point in the systemwhere water is blended to satisfy the desired water quality, downstream of the control point. The desalinated water is blended with brackish groundwater extracted from several groundwater wells. The objective of the model is to minimize the goal deviations from the following priority levels: demand for blended water, control of salinity levels, depletion of groundwater and maximize the use of brackish water, demand forbrackish water at WBS, and production of desalinated water. Anessential element of the model is the input data; unfortunately,available data are not accurate due to the inherent uncertaintyassociated with it. This uncertainty will generate uncertainty in the model output, which affects reliability and confidence associated with the decisions. Thus, reliable planning should consider uncertainties associated with model input parameters.The developed stochastic model shows how Goal Programming (GP)modeling can be used to plan the water resources in the EasternProvince of Saudi Arabia, assuming that both supply and demandare uncertain.     

淮河洪汝河流域“多水源—多用户”供水联合调度模型研究及应用

以洪汝河流域为研究对象,基于水库、河道、地下水、区域地表水及其他水资源5类供水水源与12个需水区、县单元的“多水源—多用户”的水资源配置方案,构建系统模拟模型,并进行可视化软件开发。模型采用流域内1997年1月至2006年12月实测降雨资料计算的分区来水成果和通过需水预测得到的2030年水平需水量进行模拟计算,通过供水保障程度等计算结果评价模拟模型和水资源配置方案的合理性,另外软件通过可调节参数的设定增加模型的适应性。结果验证表明,本模型对于研究洪汝河流域区域水资源供、需平衡关系及既有水资源配置方案的合理性,以及模拟预测各年型区域水资源配置保障程度有很好的效果。     

玛纳斯河流域山前平原区地下水系统模型研究

新疆干旱少雨，冰川融水季节性较强，要满足工、农业的快速、持续发展，需合理有效地开采、利用地下水资源。玛纳斯河流域周边地区经济发展较快，以灌溉为主的农业生产及工业发展更离不开水资源的供给。本文分析了玛纳斯河流域平原区地下水资源赋存特点，依据开采区含水层水文地质特征，在对研究区边界及初始条件进行合理概化基础上建立了地下水系统模拟模型。考虑到地下水资源动态变化受人工开采型、水文-人工开采型、气候型等混合形式影响的特点，将水资源补给、排泄项划分到7个时段，研究区划分为620个单元和339个结点，采用有限元方法对模型进行数值离散，在边界条件及垂向水交换量进行动态模拟基础上对潜水和承压水非稳定流动态流场进行了拟合，拟合结果中误差小于0．5m的结点数超过总结点数的85％。得到了该区地下水系统水文地质参数，实现了地下水开采较大的冲洪积扇区较高精度的水资源动态模拟，同时为水资源变化预报预测提供了可靠参数及模型基础。     

An Integrated DSS for Groundwater Management Based on Remote Sensing. The Case of a Semi-arid Aquifer in Morocco

A Decision Support System has been set up as the result of a fruitful cooperation between several public and research institutions in the framework of a large cooperation program. The DSS aims to compare spatially and temporally sectorial water demands of the Haouz-Mejjate plain (Morocco) in regard to available surface and groundwater resources. It is composed of a tool for satellite estimation of Agricultural Water Demand (SAMIR), a tool for integrated water resources planning (WEAP) and a groundwater model (MODFLOW) each of them relying on a common Geographical Information System not described here. The DSS is operating on a monthly time scale. Agricultural water demand accounts for about 80?% of the total demand. In areas where groundwater abstraction is difficult to quantify by direct methods, multitemporal remote sensing associated to the FAO methodology is a simple and efficient alternative to estimate Evapotranspiration (ET). In this work, a monthly estimate of ET from irrigated areas is derived from freely available MODIS NDVI for the 2001?C2009 period. An important part of the paper deals with the validation of these estimates with eddy covariance flux measurements installed on different irrigated crops of the region. Results are satisfactory with a minus 6.5?% error per year on the monthly time scale. This preprocessing allows to dichotomize irrigated versus non-irrigated areas, and then, to estimate groundwater abstraction in subareas distinguishing by their operating modes: traditional, dam or privately irrigated. A dynamic linkage between MODFLOW and WEAP transfers the results of one model as input data to the other. The model restitutes both spatial and temporal variations in head charges and allows the calculation of the ground water balance. After calibration, piezometric validation is acceptable for the majority of the 21 head control points.     

滨海盆地变密度地下水流与溶质运移三维耦合数值模型研究

针对滨海含水层的复杂性,以北部湾经济区合浦盆地地下水资源应急潜力评价为例,通过概化出合浦盆地水文地质概念模型的基础上,采用SEAWAT模块建立了合浦盆地变密度地下水流与溶质运移三维耦合数值模型。在对模型进行识别、验证的基础上,假设2025年10月出现极端干旱,在保证不发生海水入侵的条件下,获得了度过整个枯水期各水源地地下水资源应急潜力。结果表明:合浦盆地地下水资源应急潜力为83.13万m~3/d,集中开采区中心地下水水头下降3～8 m, 2 a后水位基本恢复;集中开采区降落漏斗远离海岸线,不受到海水入侵的影响。该方法将滨海水源地地下水应急供水预测和盆地的水文地质结构及当地发展规划紧密结合起来,为合浦盆地地下水资源的合理开发利用和应急能力建设提供了可靠依据。     

Groundwater modeling and demarcation of groundwater protection zones for Tirupur Basin – A case study

Groundwater is a renewable resource and has to be protected from contamination. The concept of a zone of protection for areas containing groundwater has been developed and adopted in a number of countries. One such area is Tirupur, (Tamil Nadu, India) which is an arid region and rapid expansion of the textile industry has taken place with no associated development of supporting infrastructure or institutional capacity. Textile production, particularly dyeing and bleaching is water intensive and generates large quantities of effluent. One of the most significant challenges for the Tirupur textile industry today is water for bleaching and disposal of effluent. Demarcation of groundwater protection zones has become necessary to facilitate recharging of the aquifer to meet the water demand. These zones are considered sensitive zones and should be free from activities such as the groundwater over exploitation, effluent discharge and construction of barriers. Groundwater flow for Tirupur Block was simulated using visual MODFLOW version 4.1. The model was run for the year 1998–99 with transient flow condition. Taking June 1998 water level as initial head, the model was run to simulate water level up to May 1999 and validated with the observed data for all the six wells which are distributed over six different zones. The results obtained from the simulation were used to assign the ranks and weights for overlay process in Geomedia environment. The consequent higher index values indicate the sensitivity zone influencing recharge to the aquifer which should be demarcated as groundwater protection zones. This groundwater protection zone will be designated as pollution free zone for better management of the aquife.     

Management Strategy of Groundwater Resources and Recovery of Over-Extraction Drawdown Funnel in Huaibei City, China

Groundwater overexploitation is threatening our ecosystems and even the life of future generations. Once happens, elimination of the bad influence will be a long-term process. It should be a feasible approach to take the environmental recovery as a whole by the way of the groundwater management. A case study of water resources management in Huaibei city, within semiarid region of north Anhui province, China, was illustrated, especially on the issues of groundwater over-extraction drawdown funnel recovery. Taking into account the water demand for satisfying the urban development in the next 15 years, three target years of water resources planning were postulated as the present (2005), the short-term (2010) and the long-term (2020), respectively. Four hydrological years: wet year, mean year, dry year and extremely dry year, were also defined by the rainfall data for many years. A groundwater management model which could deal with twelve possible scenarios (3 target years of water resources planning ×4 hydrological years) was established based on simulation and optimization. The groundwater management model could optimize the strategies of water resources development, integrate various kinds of water sources, e.g. groundwater, surface water and additive water sources, and meet the water demand for the urban development within an area of Huaibei city. Importantly, in accordance with the groundwater management model solutions, the issues of groundwater over-extraction drawdown funnel, which has formed within the Huaibei downtown area for many years and lead to some environmental and social problems, would be solved over the whole planning period.