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1.
年平均降雨入渗补给对滨海含水层系统水位波动影响的解析研究 总被引：1，自引：1，他引：0
刘双 《鞍山师范学院学报》2010,12(6):14-18
降雨入渗补给是影响滨海含水层系统水位波动的主要因素之一.本文建立了一个较为一般的滨海含水层系统模型.模型中不仅考虑了年平均降雨入渗补给对含水层系统水位波动的影响,同时也考虑了潜水含水层中地下水的波动及其通过半透层对承压含水层的越流补给.利用解析法分析了降雨入渗补给对潜水水位、承压水头和地下水海底排泄量的影响. 相似文献
2.
刘双 《鞍山师范学院学报》2011,13(2):1-4
降雨入渗补给是影响滨海含水层系统水位波动的主要因素之一,本文在文[1]的基础上,利用解析法进一步考虑了季节性降雨补给对滨海含水层系统水位波动的影响,文章同时也考虑了潜水含水层中地下水的波动及其通过半透层对承压含水层的越流补给. 相似文献
3.
土壤含水量对浑水入渗能力的影响 总被引：1，自引：0，他引：1
土壤含水量对浑水入渗能力产生明显影响,土壤含水量由小变大,浑水入渗能力减小;3个入渗参数随土壤含水量的增大而减小。研究结果对于指导浑水入渗及引洪补源具有重要意义。 相似文献
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本文对天津市宝坻地下水的赋存及分类进行了详细的阐述,对该地区的含水层进行了划分,对该地区地下水的补给、径流和排泄做出了分析,为该地区的水资源的开发和利用提供了信息基础。 相似文献
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贵阳市花溪河轮叶黑藻吸附悬浮物的探究 总被引：2，自引：0，他引：2
花溪河位于贵州省贵阳市南郊,河流水质清澈,大型水生植物丰富,水生生态保持较好。轮叶黑藻（Hydrilla verticillata）在花溪河分布较广,数量也多,它的叶片表面吸附有很多的悬浮物。我们对轮叶黑藻对悬浮物吸附的情况和叶片表面的形态进行了研究,发现它吸附悬浮物的量可达自身质量的2．59～3．52倍,叶片表面的一些结构特征有利于它对悬浮物的吸附。 相似文献
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An intrusion of contaminants into the water distribution network (WDN) can occur through storage tanks (via animals, dust-carrying bacteria, and infiltration) and pipes. A sensor network could yield useful observations that help identify the location of the source, the strength, the time of occurrence, and the duration of contamination. This paper proposes a methodology for identifying the contamination sources in a water distribution system, which identifies the key characteristics of contamination, such as location, starting time, and injection rates at different time intervals. Based on simplified hypotheses and associated with a high computational efficiency, the methodology is designed to be a simple and easy-to-use tool for water companies to ensure rapid identification of the contamination sources, The proposed methodology identifies the characteristics of pollution sources by matching the dynamic patterns of the simulated and measured concentrations. The application of this methodology to a literature network and a real WDN are illustrated with the aid of an example. The results showed that if contaminants are transported from the sources to the sensors at intervals, then this method can identify the most possible ones from candidate pollution sources. However, if the contamination data is minimal, a greater number of redundant contamination source nodes will be present. Consequently, more data from different sensors obtained through network monitoring are required to effectively use this method for locating multi-sources of contamination in the WDN. 相似文献
7.
核磁共振找水仪采集信号的特征参数准确度对地下水的研究有很重要的意义．特征参数提取是否精确直接影响了反演解释含水层位置、含水量、以及孔隙度等水文地质信息．针对特征参数的多种提取方法,本文主要围绕线性拟合、非线性拟合和自相关拟合三种数据拟合方法进行对比,找出不同信噪比下最适合的特征参数提取方法．野外实测数据和反演结果也验证了方法的有效性． 相似文献
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考察了向海底有限延伸的滨海含水层系统中由海潮及其载荷效率引起的地下水头波动.该系统由承压层和它下面的弱透水层所组成,并且向海底有限延伸,在海底露头处被一个半透水的淤泥层覆盖.本文综合考虑了弱透水层的越流、弹性储水、载荷效应以及来自淤泥层的越流对承压含水层的影响,并得出了相应的解析解.可以发现含水层下面的弱透水层的越流与弹性储水对承压含水层的水头波动也产生了很大的影响. 相似文献
10.
＂地下水运动方程＂是为地下水科学与工程专业本科生开设的一门新课程,以取代过去地下水专业的＂数学物理方程＂课程。开设这门课的目标是通过有针对性的讲解和讨论,在数学物理方程与地下水动力学之间架起一座桥梁,帮助学生更深入地利用数学知识来理解地下水的运动规律。＂地下水运动方程＂主要讲授地下水流偏微分方程的解析方法,具有很强的实用性,突出方程解法的灵活性。 相似文献
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张家口水资源忧思 总被引：1，自引：0，他引：1
白云亭 《河北北方学院学报(社会科学版)》2010,26(6):53-57
张家口是缺水城市,面临水资源危机的严重挑战。大气降水在波动中下降,地表水明显减少,地下水开发过量,水质受到污染。解决水资源问题,要加大宣传力度,提高节水意识,在城市化进程中,要充分考虑到水资源的决定作用,力保水资源不再继续污染,加强水土保持,涵养水源,造福人民。 相似文献
13.
《河流流量测验规范》第六章高洪流量测验中提出的有关水位级划分的方法,对水量丰沛的南方大河干流的计算结果相差较小,而对来水丰枯悬殊的支流小河、有水利工程影响及黄河以北季节性结冰河流,其计算结果相差甚远。作为国家标准,应该适用于国内各种河流,不宜相差甚远。本文提出了黄金分割法（或优选法）及经验法计算各站水位级,比较合理,适合各种情况的河流。推荐使用黄金分割法。 相似文献
14.
针对地表水和地下水相互作用,本文中通过追溯地表水和地下水耦合模型发展历史,总结了目前出现的各类模型。根据耦合的方式,划分为三种类型:独立型、联合型和集成型。对其中典型的模型:SWATMOD、MODBRANCH和MIKE-SHE模型进行了详细的分析介绍。对今后的研究趋势和前景进行了的探讨,为地表水-地下水的耦合模拟研究提供了参考。 相似文献
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河北省地表、地下水资源短缺,地区分布不均,且水资源浪费和水污染现象严重,这些问题一直困扰着河北省经济的发展。为此,应加强领导,制定和实施水环境保护规划,科学利用水资源,以提高水的重复利用率和效率。 相似文献
16.
Cover systems are used to prevent water infiltration into a waste body. They also play an important role in controlling landfill gas transport from the waste body to the atmosphere. It is important to assess the flux of landfill gas at the surface of a cover system by considering the coupled effects of rainwater infiltration and gas transport in the cover soils. We have developed a 1D mathematical model for coupled transient gas and water transport in unsaturated cover soils. The coupled model was solved by the finite element method. Results obtained by the proposed model agreed well with experimental data. Based on the proposed solution, the influences of gas pressure, gas permeability, and the thickness of the cover soils on soil gas concentration profiles were investigated. The difference in soil gas concentration reached up to 31% as the thickness of cover increased from 1 to 2 m. Gas concentration at a depth of 0.2 m decreased by 6% as the amplitude of atmospheric gas pressure fluctuation increased from 20 to 100 Pa. The gas concentration increased by only 3% when gas permeability increased by a factor of 2 for a relatively long period of gas migration (e.g., 60 h) under the given conditions. Results suggest that both diffusion and advection should be considered when estimating gas transport in unsaturated cover soils. The numerical model can be used in the design of cover systems in relation to gas breakthrough time, breakthrough concentration, and flux. 相似文献
17.
Bangladesh has experienced the largest mass poisoning of a population in history owing to contamination of groundwater with naturally occurring inorganic arsenic. Prolonged drinking of such water risks development of diseases and therefore has implications for children's cognitive and psychological development. This study examines the effect of arsenic contamination of tubewells, the primary source of drinking water at home, on the learning outcome of school-going children in rural Bangladesh using recent nationally representative data on secondary school children. We unambiguously find a negative and statistically significant correlation between mathematics scores and arsenic-contaminated drinking tubewells at home, net of the child's socio-economic status, parental background and school specific unobserved correlates of learning. Similar correlations are found for an alternative measure of student achievement and subjective well-being (i.e. self-reported measure of life satisfaction), of the student. We conclude by discussing the policy implication of our findings in the context of the current debate over the adverse effect of arsenic poisoning on children. 相似文献
18.
Providing model‐based accounts (explanations and predictions) of water and substances in water moving through environmental systems is an important practice for environmental science literacy and necessary for citizens confronting global and local water quantity and quality issues. In this article we present a learning progression for water in environmental systems for students in elementary through high school grades. We investigated student accounts of water and substances in water moving through atmospheric, surface, and soil/groundwater systems, including human‐engineered components of these systems. Using an iterative process of model design, assessment, and interpretation, we identified four levels of achievement in student reasoning. Levels 1 and 2 force‐dynamic accounts explain movement of water as interactions between natural tendencies of water and countervailing powers. Level 3 incomplete school science accounts put events in order and trace water and substance along multiple pathways that include hidden and invisible components. Only Level 4 qualitative model‐based accounts include driving forces and constraining factors to explain or predict where water and substances in water move in given situations. The majority of high school students on average provide accounts between levels 2 and 3. We discuss the significance of these results for citizen participation in addressing common water issues. We end with suggestions for how the water learning progression can be used to inform changes to curricula, assessment, and instruction to support students in achieving level 4 performance. © 2012 Wiley Periodicals, Inc. J Res Sci Teach 49: 843–868, 2012 相似文献
19.
Artificial neural network modeling of water quality of the Yangtze River system: a case study in reaches crossing the city of Chongqing 总被引：2，自引：0，他引：2
An effective approach for describing complicated water quality processes is very important for river water quality management. We built two artificial neural network （ANN） models, a feed-forward back-propagation （BP） model and a radial basis function （RBF） model, to simulate the water quality of the Yangtze and Jialing Rivers in reaches crossing the city of Chongqing, P. R. China. Our models used the historical monitoring data of biological oxygen demand, dissolved oxygen, ammonia, oil and volatile phenolic compounds. Comparison with the one-dimensional traditional water quality model suggest that both BP and RBF models are superior; their higher accuracy and better goodness-of-fit indicate that the ANN calculation of water quality agrees better with measurement. It is demonstrated that ANN modeling can be a tool for estimating the water quality of the Yangtze River. Of the two ANN models, the RBF model calculates with a smaller mean error, but a larger root mean square error. More effort to identify out the causes of these differences would help optimize the structures of neural network water-quality models. 相似文献
20.
童亭煤矿矿井充水条件分析 总被引：1，自引：0，他引：1
张传龙 《淮南职业技术学院学报》2004,4(3):29-31
分析了童亭煤矿矿井的充水水源、充水通道、矿井涌水量，“四含水层”是矿井主要的涌水水源之一，主采煤层顶底板砂岩裂隙水，直接影响矿井生产，水量在330m^3／h左右，10煤底板“灰岩水”在遇导水断层或陷落柱时，有突水淹井的可能。 相似文献