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1.
滑坡稳定性与地下水水位变化有密切的关系,准确预测滑坡地下水位的波动过程,能有效地开展滑坡预警并降低成本。利用中林滑坡的监测数据,建立降雨量和地下水水位的自回归分布滞后(ARDL)模型,能突破隐藏裂隙的优先流难以刻画的局限,确定降雨引起地下水水位变化的滞后时间、影响系数和有效时段。通过统计在不同降雨强度下地下水水位变幅的变异系数,分析影响滑坡地下水水位的有效降雨量阈值,并对ARDL模型进行修正。将模型预测值与实测值进行对比,验证模型对滑坡地下水水位预测的有效性。研究表明,修正后的模型能更好地预测强降雨条件下滑坡地下水水位迅速涨落的过程。  相似文献   

2.
SOM-RBF神经网络模型在地下水位预测中的应用   总被引:1,自引:0,他引:1  
利用自组织映射(SOM)聚类模型优化径向基函数神经网络(RBFN)隐层节点的方法,减小了RBFN由于自身结构问题在地下水水位预测中产生的误差。采用SOM对已有样本进行聚类,利用聚类后的二维分布图确定隐层节点的数目,并根据聚类结果计算径向基函数的宽度,确定径向基函数的中心,由此建立SOM-RBFN模型。以吉林市丰满区二道乡为例,采用2000—2009年观测的地下水位动态资料,利用SOM-RBFN模型对地下水位进行预测,验证其准确性,并分别以5、7、10a的地下水位动态数据为研究样本建立模型,考查样本数量对预测结果的影响。研究结果表明:SOM-RBFN模型预测地下水水位过程中,均方根误差(RMSE)的均值为0.43,有效系数(CE)的均值为0.52,均达到较高标准,因此SOM-RBFN模型可以作为有效而准确的地下水水位预测方法;同时RBF7的RMSE和CE均值分别为0.38和0.68,结果优于RBF5和RBF10,这就意味着在模型计算中样本数量不会直接影响预测结果的精度。  相似文献   

3.
针对地下水水位变化复杂性,采用模拟生物有机体演化方式的数据处理组合方法,预测地下水水位动态变化特征。克服了常用数学方法和模型在预测复杂对象时精度低的缺点。该方法应用于地下水水位动态预测中,能很好地反映地下水的周期性动态变化特征,并具有较高的预测精度。  相似文献   

4.
郑黎  刘涵  杜海波  周兵 《地下水》2012,(4):77-77,134
以陕西省宝鸡峡灌区一典型井的水位埋深数据为资料,运用回归分析,傅立叶级数频谱分析及自回归模型分析等方法,建立地下水埋深的非平稳时序模型。采用该模型对该典型井未来水位埋深进行预测,将预测结果与实测数据进行对比。分析该模型的预测精度及其误差来源,阐述其应用于地下水动态预报的可行性,从而对如何提高该模型预测精度提出建议。  相似文献   

5.
GM(1,1)动态模型在吴江市地下水水位预测中的应用   总被引:1,自引:0,他引:1  
以吴江市地下水水位预测为例,详细阐述了地下水水位时间序列的GM(1,1)动态模型的原理和建立过程,并根据模型的预测值和实测值,对模型的精度进行了检验,结果表明,模型的预测精度达到了99.27%,等级属于Ⅰ级,具有实际的应用价值,为地下水资源的科学管理提供了依据。  相似文献   

6.
黑河中游盆地水资源转化规律研究   总被引:2,自引:1,他引:1  
基于近二十多年黑河中游盆地的地表水和地下水观测资料,通过对盆地水资源转化规律的认识,利用水文系统分析法分析了该区域地表水、地下水相互转化规律,建立了盆地出口断面水资源量转化模型和盆地平均地下水水位变幅变化模型,经模型计算值与实测值比较吻合的较好,故可运用模型预测该盆地出口断面的水资源量和地下水水位的变化幅度。根据黑河出山径流不同频率的来水量,预测了现状条件下中游绿洲区平均地下水水位的变化幅度。得出了应该充分利用地表水和地下水的相互转化提高水资源的总体利用率,单方面考虑提高地表水利用率的做法有可能破坏地下水资源、降低水资源的总体利用率和造成生态与环境恶化的结论。  相似文献   

7.
无网格法在地下水水位预测中的应用   总被引:1,自引:0,他引:1  
基于移动最小二乘理论的无网格法是近几年来兴起的一种新的数值计算方法,与有限元法相比,它的主要优点在于无需单元信息,只需节点信息。用无网格法构造了场函数,包括基函数和权函数的选取,形函数及其导数的计算。根据鞍山市首山区水文地质条件,建立了求解双层渗流二维平面系统的数学模型,详细推导了模型求解的无网格方程。应用已识别的参数,用无网格法对该数学模型进行了求解, 并对该区的地下水水位进行了预测,预测的水位与实际水位变化规律基本一致。  相似文献   

8.
灰色GM(1,1)模型是基于灰色系统理论的一种预测方法,具有对历史样本数量要求少、计算简便、验证方便等优点,在诸多领域得到广泛应用。本文建立GM(1,1)模型对江苏省丰县III承压地下水水位埋深进行预测,详细阐述了地下水水位埋深时间序列的GM(1,1)模型的原理和建立过程,根据模型的预测值和实测值,对模型的精度进行检验,并对预测结果进行了分析。结果表明:丰县各水位埋深监测点GM(1,1)数学模型精度均达到I级,预测2018-2020年丰县地下水水位呈现逐年下降趋势,水位降落漏斗将不断扩大。丰县应积极寻求地表水源,在徐州市区域供水一体化形势下尽快启用小沿河地表水,科学合理开发利用地下水资源,保证区域水资源均衡发展。  相似文献   

9.
乌鲁木齐河流域北部平原局部地区出现了地下水水位下降和生态环境退化等问题。为了实现地下水可持续开发利用,结合《乌鲁木齐市水资源综合规划报告》和《米东新区水资源规划报告》设计了现状开采方案、增加补给量方案、减少开采量方案和增加补给量与减少开采量联合方案。运用北部平原地下水非稳定流模型对这四个地下水开发情景模拟方案进行了模拟,模拟的时间段为2007~2050年。对预测期间地下水水位的动态变化、地下水水位降深及水均衡进行了分析,确定了增加补给量与减少开采量联合方案是乌鲁木齐河流域北部平原地下水的可持续开采方案。实施该方案应从北水南调引0.7×108m3/a地表水用于北部倾斜平原的农业灌溉,同时要减少地下水超采地区的地下水开采量0.50×108 m3/a。  相似文献   

10.
乌鲁木齐河流域北部平原局部地区出现了地下水水位下降和生态环境退化等问题。为了实现地下水可持续开发利用,结合《乌鲁木齐市水资源综合规划报告》和《米东新区水资源规划报告》设计了现状开采方案、增加补给量方案、减少开采量方案和增加补给量与减少开采量联合方案。运用北部平原地下水非稳定流模型对这四个地下水开发情景模拟方案进行了模拟,模拟的时间段为2007~2050年。对预测期间地下水水位的动态变化、地下水水位降深及水均衡进行了分析,确定了增加补给量与减少开采量联合方案是乌鲁木齐河流域北部平原地下水的可持续开采方案。实施该方案应从北水南调引0.7×108m3/a地表水用于北部倾斜平原的农业灌溉,同时要减少地下水超采地区的地下水开采量0.50×108 m3/a。  相似文献   

11.
孟蒙  陈智强  黄达  曾彬  陈赐金 《岩土力学》2016,37(Z2):552-560
受库水位涨落及降雨等影响,库区滑坡位移表现出明显的周期性。基于位移时间序列分析,将滑坡监测位移分解为趋势项与周期项之和。趋势项反映滑坡变形的长期趋势,其主要受滑坡本身地质结构等因素影响。周期项反映滑坡变形的波动性,其主要受外部因素影响。以三峡库区巫山塔坪滑坡为例,考虑长江水位与降雨量影响,采用H-P滤波法从滑坡位移中分解出趋势项及周期项,利用差分自回归滑动平均模型(ARIMA)对趋势项进行平稳处理并计算趋势项预测值,利用向量自回归模型(VAR)计算周期项预测值。趋势项预测值与周期项预测值之和为滑坡位移预测值。与实际监测值及多种方法分析比较,表明综合预测所得结果能较好反映滑坡变形的趋势性和波动性,位移预测效果较好。  相似文献   

12.
Groundwater systems in coastal aquifers may be affected by sea level change as increased seawater intrusion occurs with sea level rise. Artificial pumping taking place at the same time will increase this impact. In order to estimate the vulnerability of groundwater systems with sea level rise within coastal aquifers in South Korea, long-term groundwater data were analyzed using basic statistics, trend analysis, and correlation analysis. Conductivity depth profiling was also periodically conducted. Groundwater levels increased in wells with relatively low groundwater elevations but decreased in wells with higher groundwater elevations. At the same time, conductivity variations were greater in wells located in reclaimed land areas, which vertical conductivity profiles indicated were more affected by sea level variations, but decreased on the mainland. Results of auto-correlation analysis showed a decreasing trend with cyclic variations and significant periodic patterns during dry seasons, indicating that groundwater levels were not affected by artificial factors and that those in reclaimed land areas were less affected by rainfall than on the mainland. These results coincided with those from cross-correlation analysis showing that groundwater level was affected by sea level variation during the dry season. Sea level changes, which may be related to climate change, as well as rainfall in South Korea can influence groundwater levels, and the groundwater system in reclaimed land areas may be more affected than on the mainland, especially under dry conditions.  相似文献   

13.
In order to simulate the recovery of groundwater funnels under the condition of reducing groundwater abstraction, hydrogeological conditions of recoverability construction of Shijiazhuang groundwater funnel were analyzed, and a numerical simulation method was used based on the change of various parameters. The results show that the groundwater flow model can accurately reflect groundwater hydrogeological characteristics, and can guarantee the reliability of groundwater restoration prediction. The research has set up four schemes for rural water-saving, planting structure adjustment, urban reducing abstraction and integrated method. The effect of four restoration schemes on the restoration of groundwater funnels was compared with water table variations of two observation well. Comparison results show that the level changes of plan Three and Four are different from the other two kinds of exploitation and the drop trend of water table in the funnel area is flat. So we can conclude that Plan Three and Four have significant effect on the groundwater funnel restoration of Shijiazhuang.  相似文献   

14.
Access to water resources is one of the major challenges being faced worldwide. Water scarcity, particularly groundwater resource, is the major ubiquitous concern for the country. Almost half of the country is reeling under severe ground water crisis due to anthropogenic and natural reasons (basalt rock surface). Agra region situated in the western part of Uttar Pradesh state of India has a semi-arid climate. The study area, which has a history of water scarcity since medieval ages, has seen a spurt of acute water shortage in recent times owing to the expansion of a very dense built-up area and excessive haulage accompanied by decline in rainfall. A study was under taken for identifying the trends in pre- and post-monsoon groundwater levels for Agra city, Uttar Pradesh. Pre-monsoon and post-monsoon groundwater depth data of 16 observation wells for the 2007–2016 period were collected and analyzed using ARC GIS 10.2 software. The rainfall trend during the study period was also studied to understand its role in groundwater fluctuation level. Statistical tests like Mann-Kendall, Sen’s slope estimator, and linear regression model were applied to understand the trend and rate of change in groundwater level. The land use/land cover map of the study area was integrated with groundwater map to have a primary understanding of the spatial trend of groundwater scenario of the study area. The result obtained is quite alarming for the city’s groundwater scenario. Results showed that the groundwater levels had significantly declined during 2007–2016. Average rates of water level decline were 0.228 and 0.267 m/year during pre- and post-monsoon seasons, respectively. There was a rapid decline in water level between 2008 and 2009 and between 2013 and 2014. The average rate of decline of pre- and post-monsoon groundwater level in the city during this period is 0.32 and 0.30 m/year, respectively. Significant decrease in groundwater level is found in 84.21% of wells for pre- and post-monsoon as obtained through Mann-Kendall analysis at 95% confidence level. During pre-monsoon season, the rate of decline according to Sen’s slope estimator varied between 0.74 and 2.05 m/year. Almost similar picture of decline is portrayed through linear regression slope wherein the computed rate of decline varied between 0.75 and 2.05 m/year. During post-monsoon, the rate of decline according to Sen’s slope varied between 0.13 and 1.94 m/year. Similar trend statistic is obtained through linear regression method where the declining rate is between 0.14 and 1.91 m/year. Comparison of the three statistical tests indicates similar nature of declining trend. The result of this research raises concern about the future of groundwater resources in Agra city. The findings of this study will assist planners and decision-makers in developing better land use and water resource management.  相似文献   

15.
天津地区深层地下热水开采动态分析   总被引:5,自引:3,他引:2  
深层地下热水由于多年长期开采致使水位持续下降,同时由于每年采暖期和非采暖期的交替开采,水位在下降过程中又呈现周期性的波动。另一方面受温度差异的影响,钻井井口水位并不能反映深层地下热水的实际水位,应对实测水位进行校正,校正后的水位具有复杂的周期性变化和趋势性变化。本研究通过对天津地区深层地下热水开采动态分析,建立趋势项与周期项之和的数学模型来描述水位变化。用线性函数拟合其趋势项,用傅立叶级数拟合其周期项,用Welch法对周期项进行频谱分析,利用最小二乘法确定周期项函数。用校正水位和计算水位的均方差检验拟合结果,结果表明拟合效果好。所建立的数学模型可以用来预测深层地下热水动态变化,预测水位能较好地反映水位变化特点。  相似文献   

16.
To determine the relative impact of climate and human intervention on groundwater elevations in western Victoria, southeast Australia, bore hydrograph fluctuations in three aquifers were modelled using a transfer function noise model (PIRFICT) and an auto-regressive model (HARTT), which give generally comparable results. Most of the groundwater-level fluctuations (>90%) are explained by climatic variation, particularly rainfall. The overall non-climate-related trend in groundwater level is downward and small but statistically significant (??.04 to ??.066 m/yr), and is probably due to the widespread replacement of grazing land by wheat and canola cultivation, as these crops use more water than pasture. A large non-climate-related trend (??.30 m/yr) for bores in an irrigation area is mainly related to groundwater extraction. The response time of the system is rapid (only 4.85 years on average), much faster than previously estimated. Rates of groundwater flow are much slower; groundwater ages are up to ~35,000 years. Response times effectively represent the time for the system to move to a new state of hydrologic equilibrium; this prediction of the time scale of the impacts of land-use change on groundwater resources will allow the development of better strategies for groundwater management.  相似文献   

17.
通过分析临沂市城区岩溶塌陷与地下水活动的关系,确定了岩溶塌陷的主控因子为地下水水位。借助已建立的地下水流模型,提出控制岩溶塌陷的方法,即使岩溶水水位不低于控制水位。以此为目标在研究区选定若干具有代表性的水位控制点,并设计了三种地下水规划开采方案,将其带入地下水流模型演算,最终获得合理的地下水开采方案,即未来城区岩溶水开采量与现状开采相比减少了11.65×104m3/d,减少的水量由临沂市岸堤水库地表水工程解决。该方案实施后可在一定程度上控制岩溶塌陷发生的危险。  相似文献   

18.
为了提高区域地下水资源评价的可靠性、扩展干旱半干旱地区面向生态的区域地下水资源评价方法,对准噶尔盆地和鄂尔多斯盆地地下水与生态环境关系进行调查研究,认为地下水具有重要的生态价值。目前在干旱半干旱地区区域地下水资源评价中对地下水的生态价值考虑不够,是造成地下水资源评价可靠性不高的原因之一。因此,提出了干旱半干旱地区地下水生态价值的概念,围绕可持续利用的地下水资源量与生态环境良性循环的目标,构建了面向生态的区域地下水资源评价方法体系。方法体系的基本思路是突出系统的观点和地表水与地下水统一评价、水质水量并重、地下水资源与其相关生态环境统一评价的3个原则;通过建立水文地质概念模型、集中参数型模型、分布参数型模型和基于地下水变化的生态环境综合评价4个模型,加上引进水量、水位与水质3个约束条件,以及开发基于GIS的地下水资源评价信息系统的平台,对地下水资源、调蓄能力与生态环境效益进行整体评价与预警。方法体系注重了地下水的资源和生态的双重属性,强调地下水资源与相关生态环境整体评价和预警的一体化,突出了模型体系与GIS技术在区域地下水资源评价和相关生态环境评价的有效集成。  相似文献   

19.
频谱分析法在吉林西部地下水动态预报中的应用   总被引:9,自引:0,他引:9  
本文应用频谱分析法对吉林西部的地下水动态进行了分析和预报,用傅立叶级数将消除趋势成分后的水位序列在一定区间上展开,分析谱参数之间的函数关系,建立预报模型。对模型进行分析可知该区地下水位存在两个主要周期(1年和6~8年) ,反映了地下水位的季节性变化和气候变化规律;2 0 0 2年以后的预报结果表明部分地区的地下水位将持续下降,应及时加以控制。为吉林西部的地下水开发和水资源管理提供了依据。  相似文献   

20.
模糊模式识别法在评价地下水水质中的应用   总被引:3,自引:0,他引:3  
李新峰  刘国东 《地下水》2008,30(4):9-11
采用模糊模式识别法评价地下水水质,提出了相对隶属度理论,通过距离平方和最小的准则,建立目标函数,可得地下水水质的变化趋势,更符合当代地下水水质评价的要求。应用该法评价太原市地下水,得到了满意的结果。  相似文献   

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