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851.
基于ArcGIS Engine的地下水资源及其地质环境信息系统设计与实现 总被引:6,自引:1,他引:5
针对研究区内需要处理的数据量大、数据种类与格式复杂的特点,利用国际上最先进的ArcGIS Engine技术和Visual Basic.NET开发平台,建立了东北地区地下水资源及其地质环境信息系统,将空间数据库与属性数据库联合集成,实现了空间数据分析、图文双向查询、图表自动生成、多媒体链接以及数据库管理等多种功能,能够为区域地学、水资源、环境生态等领域的研究、管理和决策提供空间信息和统计信息等综合信息服务。 相似文献
852.
吉林中部平原区地下水温动态变化影响因素的关联度分析 总被引:6,自引:0,他引:6
以吉林中部平原区为例,分析了孔隙潜水、孔隙承压水以及白垩系孔隙裂隙承压水温度的多年变化特征,并采用灰色关联度分析方法,确定了各含水层地下水温度与地下水埋深、气温、降水量之间的关联性,分析了影响其变化的主要因素。结果表明,对于3组含水层,从20世纪80年代初至2001年的近20年间,地下水温度都有不同程度的上升。对于孔隙潜水和孔隙承压水,地下水温度呈上升变化的本质原因是全球气候逐年变暖,而地下水活动和大气降水的增强起到了促进作用,特别是对孔隙承压水温度的上升作用更加明显;对于白垩系孔隙裂隙承压水,其温度呈上升变化则主要是由该含水层被普遍超采所引起的。 相似文献
853.
854.
Irina Gaus 《Hydrogeology Journal》2000,8(2):218-229
Pesticides are a potential threat to the quality of extracted groundwater when the water-supply area is used for agricultural
activities. This problem is discussed for the water-supply area of Sint-Jansteen, The Netherlands, where measured pesticide
concentrations in the extracted water regularly exceed EU limits (0.1 μg/L). Groundwater samples taken from the aquifer within
the water-supply area show low contamination, but samples taken from the extracted water occasionally contain pesticides,
making the water inadequate for drinking-water purposes. The more intense contamination of the extracted water is caused by
the change in the natural groundwater flow pattern near the extraction wells. In this area, pesticide use cannot be avoided
easily, and an approach is given to differentiate pesticide use in the area according to expected travel time toward the wells
and the chemical characteristics of the pesticides. A groundwater flow model for the area is developed and the effects of
groundwater extraction on the natural flow pattern are evaluated. Using particle tracking, the travel-time zones are determined.
Combining these results and the degradation behavior of certain pesticides led to an optimal scheme to integrate agricultural
activities and groundwater extraction in the area. This is illustrated for five different types of pesticides (atrazine, simazine,
bentazone, MCPA, and mecoprop).
Received, October 1998/Revised, July 1999, September 1999/Accepted, November 1999 相似文献
855.
Groundwater contamination due to accidental releases of mono- and polycyclic aromatic compounds (MAHs and PAHs) from decommissioned
manufactured-gas plants is an ongoing and litigious problem. The MAHs and PAHs are derived from coal tar, which was a by-product
of the gas-manufacturing process. While originally designed to contain coal tar, the manufactured-gas plant structures that
remain today have often degraded over time and are not completely leak-proof. Over a period of many years, subsurface water
has seeped into and out of the structures, resulting in groundwater contamination. This was particularly true once the tops
of the structures were removed. In this study, process-based simulations were conducted to estimate the groundwater-quality
impacts of accidental releases of dissolved naphthalene (C10H8) from the sites of three former manufactured-gas plants. The results from one-dimensional, transient, unsaturated, near-surface
fluid-flow and solute-transport simulations served as input to three-dimensional saturated subsurface fluid-flow and solute-transport
simulations. The simulation results and sensitivity analysis reported here indicate that accidental releases of naphthalene
had significant, negative impacts on groundwater quality at each of the three sites.
Electronic Publication 相似文献
856.
对大空间尺度和长时间跨度的地下水流动及污染物质运移进行预测的需求, 使水文地质研究面临异乎寻常的挑战.这些需求来自于对核废料地质储放方法的安全性评价、地下水污染状况评价及其治理方案的选择.流动系统的非均质性是地下水流动及物质运移模拟中最主要的困难之一, 这种困难来自对非均质系统进行特征描述(通过原位观测实现)、概念化及模拟.评述了非均质介质中流动运移模拟的一些重要问题与挑战, 讨论了解决的途径.讨论的主题包括: 动力流动的沟道化, 示踪剂穿透曲线, 裂隙岩石中流体流动的多尺度, 观测的不同尺度, 模拟、预测与非均质性以及系统特征描述和预测性模拟的分析. 相似文献
857.
L. Li D. A. Barry C. Cunningham F. Stagnitti J. -Y. Parlange 《Advances in water resources》2000,23(8):176
Previous studies on tidal dynamics of coastal aquifers have focussed on the inland propagation of oceanic tides in the cross-shore direction, a configuration that is essentially one-dimensional. Aquifers at natural coasts can also be influenced by tidal waves in nearby estuaries, resulting in a more complex behaviour of head fluctuations in the aquifers. We present an analytical solution to the two-dimensional depth-averaged groundwater flow equation for a semi-infinite aquifer subject to oscillating head conditions at the boundaries. The solution describes the tidal dynamics of a coastal aquifer that is adjacent to a cross-shore estuary. Both the effects of oceanic and estuarine tides on the aquifer are included in the solution. The analytical prediction of the head fluctuations is verified by comparison with numerical solutions computed using a standard finite-difference method. An essential feature of the present analytical solution is the interaction between the cross- and along-shore tidal waves in the aquifer area near the estuary’s entry. As the distance from the estuary or coastline increases, the wave interaction is weakened and the aquifer response is reduced, respectively, to the one-dimensional solution for oceanic tides or the solution of Sun (Sun H. A two-dimensional analytical solution of groundwater response to tidal loading in an estuary, Water Resour Res 1997;33:1429–35) for two-dimensional non-interacting tidal waves. 相似文献
858.
859.
860.
地下水资源是陕西实施西部大开发战略的重要保证 总被引:2,自引:0,他引:2
陕西在西部大开发中具有重要地位和良好前景。陕西是一个缺水省份,但存在着地下水赋存的良好地质-水文地质条件,地下水资源是陕西实施西部大开发战略的重要保证。面对西部大开发的新形势,依法加大陕西地下水资源勘查开发力度,把地下水资源勘查开发同其它基础建设要放在同等重要位置。组建专业委员会研讨地下水资源勘查开发问题。 相似文献