Geospatially based distributed rainfall‐runoff modelling for simulation of internal and outlet responses in a semi‐forested lower Himalayan watershed     

RAAJ Ramsankaran  U. C. Kothyari  S. K. Ghosh  A. Malcherek  K. Murugesan 《水文研究》2012,26(9):1405-1426

This study presents a Geographic Information System (GIS)‐based distributed rainfall‐runoff model for simulating surface flows in small to large watersheds during isolated storm events. The model takes into account the amount of interception storage to be filled using a modified Merriam ( 1960 ) approach before estimating infiltration by the Smith and Parlange ( 1978 ) method. The mechanics of overland and channel flow are modelled by the kinematic wave approximation of the Saint Venant equations which are then numerically solved by the weighted four‐point implicit finite difference method. In this modelling the watershed was discretized into overland planes and channels using the algorithms proposed by Garbrecht and Martz ( 1999 ). The model code was first validated by comparing the model output with an analytical solution for a hypothetical plane. Then the model was tested in a medium‐sized semi‐forested watershed of Pathri Rao located in the Shivalik ranges of the Garhwal Himalayas, India. Initially, a local sensitivity analysis was performed to identify the parameters to which the model outputs like runoff volume, peak flow and time to peak flow are sensitive. Before going for model validation, calibration was performed using the Ordered‐Physics‐based Parameter Adjustment (OPPA) method. The proposed Physically Based Distributed (PBD) model was then evaluated both at the watershed outlet as well as at the internal gauging station, making this study a first of its kind in Indian watersheds. The results of performance evaluation indicate that the model has simulated the runoff hydrographs reasonably well within the watershed as well as at the watershed outlet with the same set of calibrated parameters. The model also simulates, realistically, the temporal variation of the spatial distribution of runoff over the watershed and the same has been illustrated graphically. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

一种基于非曼哈顿结构的Over-The-Cell布线算法研究     

许飞  汤银英  虞厥邦 《成都信息工程学院学报》2007,22(1):55-59

提出了一种基于非曼哈顿结构的单元上（Over-The-Cell，OTC）布线算法。算法第一次在单元上布线中采用非曼哈顿布线结构，并根据算法特点提出了线网和边相关系数的概念。实践证明，得益于单元区线网选择时对线网和边相关系数的应用，算法和传统标准单元详细布线算法相比，可以进一步降低通道高度和减少通孔数量。  相似文献   

流域水文与地貌特征关系研究的回顾与展望   总被引：3，自引：0，他引：3       下载免费PDF全文

芮孝芳  蒋成煜 《水科学进展》2010,21(4):444-449

揭示水文过程与地貌过程相互作用的定量关系是水文学家长期追求的目标,也是新国际水文10年PUB计划的重要内容之一。论述了建立这两者定量关系的统计综合途径和具有物理基础途径的思路方法与主要特点,述评一个多世纪以来,尤其是近30年来国外学者在这方面所作的研究,介绍了作者近年来在这方面所做的工作。  相似文献   

下边界条件为水位流量关系的扩散波洪水演算方法研究          下载免费PDF全文

黄国如  胡和平  田富强  尹大凯 《水科学进展》2001,12(4):479-484

经大量的理论分析和实际洪水演算表明,扩散波可较好地反映洪水波的运动特点。本文基于河道下断面的水位流量关系和连续方程的联立求解,导出了水位流量关系型的下边界条件。利用Laplace变换,得到了扩散波方程在该边界条件下的解析解。文中的求解过程表明,可利用该法进行洪水演算,关键在于如何与实际洪水结合,这个问题有待进一步地分析研究。  相似文献   

GIS和SDSS在高速公路选线之中的应用   总被引：6，自引：1，他引：6  

贾永刚  广红等 《地球科学》2001,26(6):653-656

以地理信息系统（GIS）和空间决策支持系统（SDSS）技术为基础，以地理信息系统工具CITYSTAR为平台，以VB为开发工具，在高速公路选线理论的指导下并考虑选线工作中的实际问题，对如何把GIS和SDSS应用到高速公路选线中进行了探讨，并以青岛、黄岛、灵山卫、南岭等环胶州湾地区为研究对象，初步设计出了高速公路选线决策支持系统。  相似文献   

Rapid assessment of field erosion and sediment transport pathways in cultivated catchments after heavy rainfall events     

P. M. van Dijk  A.‐V. Auzet  M. Lemmel 《地球表面变化过程与地形》2005,30(2):169-182

This paper explores a scale‐adapted erosion mapping method which aims at a rapid assessment of field erosion and sediment transport pathways in catchments up to several square kilometres and compares the results with the output of a well‐known erosion model (LISEM). The mapping method is based on an event‐defined classification scheme of erosion intensity (zero, weak, moderate and strong) that is applied to arable fields, in combination with incision measurements of erosion features for each erosion intensity class on a small sample of fields. Sediment deposition is classified on the basis of quantity indicators and abundance. In addition, relevant conditions and erosion factors are determined for each field. The method was applied to an agricultural catchment (4·2 km²) in the Sundgau (Alsace), after a short but violent thunderstorm in May 2001, to illustrate its potential use and its limitations. The rainfall event led to strong erosion on the arable fields and a muddy flow that caused significant damage in the built‐up area. On the basis of the analyses of the incision measurements in combination with the mapping of erosion intensity classes, total erosion for the catchment was estimated as 15 000 t (an average of about 36 t[sol ]ha). Sediment deposition was found to occur in three major locations: (1) in thalwegs at the interface between maize and downslope winter wheat fields, (2) in downslope headlands where the flow direction suddenly changed due to oriented tillage structures in the perpendicular direction, and (3) the lowest corners of fields which collect all the runoff from the field. Preliminary data analyses suggest that erosion intensity is related to field size and[sol ]or tillage direction and to slope morphology. Model output (LISEM) appeared to depend more strongly on slope gradient than the results obtained with the mapping method. The method yields a database, which can be used as a foundation for conservation strategies in small regions with similar land use and geomorphology. The mapping and modelling methods are compared, and their complementary aspects are highlighted. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

滩槽流量分别演算法进行汾河下游河段洪水预报     

陈阆笙  曹建业 《水文》1998,(1):33-38

汾河下游柴庄以下河段由于受人为和处在然等多种因素影响,河道发生持续淤积,过水能力大幅度降低,使河道行洪特点发生很大变化,正常洪水预报方法失效。  相似文献   

PROBABLE MAXIMUM FLOOD FOR DAM SAFETY ASSESSMENT     

C.F.LEE 《国际泥沙研究》1996,(2)

ＰＲＯＢＡＢＬＥＭＡＸＩＭＵＭＦＬＯＯＤＦＯＲＤＡＭＳＡＦＥＴＹＡＳＳＥＳＳＭＥＮＴＣ．Ｆ．ＬＥＥ（Ｆｏｒｍｅｒｌｙ，ＭａｎａｇｅｒｏｆＧｅｏｔｅｃｈｎｉｃａｌａｎｄＨｙｄｒａｕｌｉｃＥｎｇｉｎｅｅｒｉｎｇＤｅｐａｒｔｍｅｎｔ；ＭａｎａｇｅｒｏｆＣｉ...  相似文献   

The design storm concept in flood control design and planning     

T. V. Hromadka  R. J. Whitley 《Stochastic Environmental Research and Risk Assessment (SERRA)》1988,2(3):213-239

The design storm approach, where the subject criterion variable is evaluated by using a synthetic storm pattern composed of identical return frequencies of storm pattern input, is shown to be an effective approximation to a considerably more complex probabilistic model. The single area unit hydrograph technique is shown to be an accurate mathematical model of a highly discretized catchment with linear routing for channel flow approximation, and effective rainfalls in subareas which are linear with respect to effective rainfall output for a selected “loss” function. The use of a simple “loss” function which directly equates to the distribution of rainfall depth-duration statistics (such as a constant fraction of rainfall, or a ?-index model) is shown to allow the pooling of data and thereby provide a higher level of statistical significance (in estimating T-year outputs for a hydrologic criterion variable) than use of an arbitrary “loss” function. The above design storm unit hydrograph approach is shown to provide the T-year estimate of a criterion variable when using rainfall data to estimate runoff.  相似文献   

Development of a high resolution runoff routing model, calibration and application to assess runoff from the LMD GCM   总被引：3，自引：0，他引：3  

Agns Ducharne  Catherine Golaz  Etienne Leblois  Katia Laval  Jan Polcher  Emmanuel Ledoux  Ghislain de Marsily 《Journal of Hydrology》2003,280(1-4):207-228

Large-scale runoff routing models (RRMs) are important as a validation tool for GCMs, and to close the hydrological cycle in fully-coupled climate models. The model RiTHM was developed to simulate the discharge of large rivers from the total runoff simulated by the LMD GCM. It uses a 1024×800 grid, nested in the 64×50 grid of the LMD GCM. The runoff simulated in a GCM grid cell is uniformly distributed over the underlying cells, where a series of two reservoirs accounts for the delay related to infiltration through the unsaturated zone and aquifers. The resulting riverflow is routed assuming pure translation along the drainage network, extracted with a GIS from a 5 min DEM. The transfer time from a cell to the outlet depends on topography, and on a basin-wide parameter, the time of concentration. RiTHM was calibrated in 11 river basins, using a realistic runoff forcing (computed by the land surface model SECHIBA from reanalyzed meteorological forcing). This led to a very satisfactory reproduction of observed hydrographs. The main problems were related to hydraulic processes neglected in RiTHM (reservoirs, diversion of riverflow because of flooding or irrigation). These results helped to validate SECHIBA, except for its snow processes, shown to be too simple. With the same parameters, RiTHM was also forced with runoff from the LMD GCM. This induced an important degradation of the simulated hydrographs, regarding both volume and timing. It was largely explained by errors in precipitation, and more generally climate, in the GCM. The direct calibration of RiTHM under the GCM-runoff forcing markedly improved the timing of simulated discharge, which could be interesting for land–atmosphere–ocean coupling. This work demonstrated that the usefulness of RRMs for GCMs strongly depends on their adequate calibration.  相似文献