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1.
Typhoon-induced extreme storm runoffs often cause flood hazards. In this study, a hydrological model (HEC-HMS) was applied to Shihmen watershed located in Taiwan. Three typhoon-induced storm events, with return period ranging from 1 to 90 years, were used in case studies to characterize storm runoff. With a 5-year storm for model calibration, model parameters were carefully calibrated through the comparison between model simulated and observed flows at a stream gage station. The calibrated model was then verified for a 90-year storm and a 1-year storm event. Results indicate that the calibrated and verified HEC-HMS hydrological model is capable of providing satisfactory predictions of the typhoon-induced extreme storm runoff to support reservoir operation and flood hazard mitigation. Based on model simulations, typhoon-induced water table increases for different initial water volumes at Shihmen Reservoir was derived by adding storm-runoff volume to the reservoir’s initial elevation-volume rating curve. Water tables above the top elevation of the dam in the reservoir indicate the need for immediate water releases to avoid the risk of overflow over the dam.  相似文献   

2.
分布式水文模型的进展及展望   总被引:33,自引:1,他引:32  
分布式水文模型是当前水文建模领域最为活跃的研究方向,是解决流域水文、生态和环境问题的有效的途径.讨论了分布式水文模型的结构、与地理信息系统和遥感技术的关系、参数标定、应用领域等问题,指出分布式水文模型发展面临的问题并展望了未来的发展方向.  相似文献   

3.
黑河流域生态—水文观测试验与水—生态集成管理研究   总被引:2,自引:1,他引:2  
对黑河流域水—生态—经济系统研究的主要内容“流域生态—水文观测试验与流域水—生态集成管理”做了概要论述。认为流域水循环、生态水、集成水管理三大科学问题的解决必需加强该领域的研究;结合黑河流域的前期基础、研究现状和能力建设,提出了近期研究的4个领域:流域水循环、水平衡与可利用水资源;流域生态—水文过程与生态环境用水;人类活动驱动的流域水—生态系统演变;流域生态—水文野外平台与流域集成环境。对此进行了进一步的阐述,对该方面研究的方法论和技术难点亦做了简述。  相似文献   

4.
It is absolutely necessary to quantify the hydrological processes in earth surface by numerical models in the cold regions where although most Chinese large rivers acquire their headstreams, due to global warming, its glacier, permafrost and snow cover have degraded seriously in the recent 50 years. Especially in an arid inland river basin, where the main water resources come from mountainous watershed, it becomes an urgent case. However, frozen ground’s impact to water cycle is little considered in the distributed hydrological models for a watershed. Took Heihe mountainous watershed with an area of 10,009 km2, as an example, the authors designed a distributed heat-water coupled (DWHC) model by referring to SHAW and COUP. The DWHC model includes meteorological variable interception model, vegetation interception model, snow and glacier melting model, soil water-heat coupled model, evapotransporation model, runoff generation model, infiltration model and flow concentration model. With 1 km DTM grids in daily scale, the DWHC model describes the basic hydrological processes in the research watershed, with 3∼5 soil layers for each of the 18 soil types, 9 vegetation types and 11 landuse types, according to the field measurements, remote sensing data and some previous research results. The model can compute the continuous equation of heat and water flow in the soil and can estimate them continuously, by numerical methods or by some empirical formula, which depends on freezing soil status. However, the model still has some conceptual parameters, and need to be improved in the future. This paper describes only the model structure and basic equations, whereas in the next papers, the model calibration results using the data measured at meteorological stations, together with Mesoscale Model version 5 (MM5) outputs, will be further introduced.  相似文献   

5.
This study presents an application of the model Soil and Water Assessment Tool (SWAT) to simulate daily and monthly water flow and sediment fluxes in the Wadi Hatab watershed (2200 km2) located in central Tunisia. The study basin is characterized by a significant climatic contrast, abrupt topography, and soil fragility, resulting thereby in flash floods and important water erosion rates. This alarming situation requires urgent interventions in order to preserve water and soil resources, implying the need for a decision tool for proper integrated management of the watershed. The model was calibrated and validated based on a comparison of simulated and observed flow rates at the basin outlet (hydrometric station Khanguet Zazia), during the periods 1987–1988 and 1989–1990, respectively. The comparison was based not only on visual inspection of the agreement between observed and simulated time series, but also on statistical parameters. Indeed, for the daily time step application, the Nash—Sutcliffe efficiency (NSE) values were 0.52 and 0.61, and the coefficient of determination (R2) was 0.54 and 0.61 for calibration and validation, respectively. As for the monthly time-step application, the obtained NSE values were 0.67 and 0.89 while R2 values were 0.83 and 0.87 for calibration and validation, respectively. This clearly shows the reasonably good agreement between simulated and observed flow rates. In terms of erosion, the model gave sediment yield values ??of 1.15 and 5.37 t/ha/year during the periods of calibration and validation, respectively.  相似文献   

6.
《Applied Geochemistry》2005,20(11):2138-2153
Recent geochemical and hydrological findings show that the water quality of the base flow of the Lower Jordan River, between the Sea of Galilee and the Dead Sea, is dependent upon the ratio between surface water flow and groundwater discharge. Using water quality data, mass-balance calculations, and actual flow-rate measurements, possible management scenarios for the Lower Jordan River and their potential affects on its salinity are investigated. The predicted scenarios reveal that implementation of some elements of the Israel–Jordan peace treaty will have negative effects on the Jordan River water salinity. It is predicted that removal of sewage effluents dumped into the river (∼13 MCM/a) will significantly reduce the river water’s flow and increase the relative proportion of the saline groundwater flux into the river. Under this scenario, the Cl content of the river at its southern point (Abdalla Bridge) will rise to almost 7000 mg/L during the summer. In contrast, removal of all the saline water (16.5 MCM/a) that is artificially discharged into the Lower Jordan River will significantly reduce its Cl concentration, to levels of 650–2600 and 3000–3500 mg/L in the northern and southern areas of the Lower Jordan River, respectively. However, because the removal of either the sewage effluents or the saline water will decrease the river’s discharge to a level that could potentially cause river desiccation during the summer months, other water sources must be allocated to preserve in-stream flow needs and hence the river’s ecosystem.  相似文献   

7.
DEM是目前用于流域地形分析的主要数据,基于DEM的水文模拟技术,在流域地形分析及水系构建等方面已形成了比较成熟的算法,给传统的水文模拟技术带来了根本性的变化。以蒲石河流域山区为例,借助流域水文软件WMS,结合ARCVIEW和SURFER软件,计算了流域的面积、周长、坡度与形状因子等参数。在生成山区数字高程模型的基础上,采用WMS嵌入的HEC-1模型对一场降雨进行了降雨径流模拟研究。  相似文献   

8.
本研究以四川省都江堰市龙池镇碱坪沟泥石流流域对象,基于HEC-HMS流域分布式水文模型,利用RS和GIS技术提取流域产汇流参数,模拟分析碱坪沟8·13泥石流的暴雨汇流过程,结合流域内土地利用类型分布,模拟降雨-径流关系,并综合考虑泥石流的相关特征参数,利用情景分析法探讨泥石流流域内的土地利用类型变化对泥石流汇流过程的影响关系。  相似文献   

9.
The necessity of estimating the degree and spatial extent of positive impacts with regard to protecting communities and properties through potential flood control projects can be considered one of the main reasons for performing flood modeling. This paper presents an overall systematic approach based on the simulation of some extreme event conditions, using a hydrological model to generate the resulting river flows and then using a hydraulic modeling exercise to decide upon floodplain evolution in the case-study area, Bostanli river basin, which has been under the threat of flooding for many years. The potential serviceability of the planned Bostanli Dam in the study area was examined by using the HEC-HMS and HEC-RAS modeling tools, both integrated with GIS functions for spatial operations. The results indicate that the dam construction as planned would have a somewhat positive impact as a potential flood control measure, since it seems to decrease the flood peaks of 68.9 and 158.7 m3/s (that would potentially be generated by 100- and 500-year storm events under current conditions) to 65.5 and 150.7 m3/s (when the dam is in operation), respectively. However, this seems to contribute little to the overall flood mitigation performance in the basin.  相似文献   

10.
GIS/RS是流域水文过程分布式模拟的重要技术支撑。结合泾河流域的实例研究,探讨了GIS支持下,基于栅格DEM流域水文特征的获取,降水、气温等资料的空间插值,以及土壤、植被等下垫面信息在水文模拟单元上的耦合。在此基础上,应用分布式水文模型对泾河流域的水文过程进行模拟。结果表明:所建模型结构上是合理的,在产流计算中泾河25个子流域在水量平衡方面误差均小于5%。潜在蒸发的模拟在趋势上与实测过程基本一致。径流模拟在4个检验站点上与实测过程的相关系数达到0.84~0.93。模型基本能够满足水资源规划与管理的需要。  相似文献   

11.
The main goal of this study is to investigate the effect of the size of the subbasins of a watershed on the hydrologic parameters and their spatial variability in an estimation of the hydrologic parameters and hydrograph of a neighbouring ungauged basin. In this paper, Hydrologic Engineering Center-Hydrologic Modelling System (HEC-HMS), a semi-distributed hydrologic model, is used to calibrate and cross-validate two flood events occurred in 1998 and then validate four other flood events occurred in 1991, 1994, 2002, and 2009 in Gokirmak Basin in Western Black Sea Region, Turkey. The basin is divided into seven different subbasins to investigate the effect of watershed partitioning on calibrated hydrologic parameters of each subbasin using the peak-weighted root mean square error method as an objective function and the hydrograph at the outlet of the whole basin. It is found out that as the geometric magnitudes of the subbasins changed, the calibrated values of the hydrologic parameters of those subbasins changed as well. Then, a neighbouring basin, Kocanaz, is considered as an assumed neighbouring ungauged basin to investigate the effect of watershed partitioning of a gauged basin on the estimation of hydrograph of a neighbouring ungauged basin. Hydrologic parameters and direct runoff hydrograph of assumed ungauged neighbouring basin are estimated from the hydrologic parameters of the HEC-HMS calibration results of Gokirmak. Statistical indicators of the simulation results for each basin partitioning were graded with respect to the boundary values of the simulation outputs to find the best alternative. The grading results show that the simulation results with a single basin gave better representation among all other partitioning except two flood events.  相似文献   

12.
渭河源区典型小流域水沙演变规律分析   总被引:3,自引:1,他引:2  
根据渭河源区清源河典型小流域实测水文资料,分析了流域水文要素的年内和年际变化规律,流域降水、径流和泥沙主要集中在汛期,5-9月降水量占全年的78.5%,5-10月径流占全年的78.7%,5-8月输沙量占全年的88.9%。受上游修建水库、水土保持等人类活动的影响,流域汛期径流和泥沙1997-2013年比1980-1996年均减少了5.9%。流域面平均降水量、平均流量、平均输沙量年际变化不稳定,总体呈减少趋势,序列最大可能变异点分别为1995年、1994年和1997年。建立了流域年降水量与年径流深、次降水量P+Pa与次径流深相关模型,相关系数达到0.902和0.860。以年最大洪峰流量为参数,分别建立了流域年径流量与年输沙量、次径流量与次输沙量关系模型,相关系数达到0.835和0.917,公式模拟值与实测值接近,误差较小,可以作为以径流推算泥沙的重要依据。通过定性定量分析人类活动对流域径流、泥沙的影响程度,对区域抗旱防洪减灾、水资源管理、小流域治理及生态环境保护具有重要意义。  相似文献   

13.
 King Talal Dam (KTD) watershed is the most important one in Jordan. At its outlet lies the KTD (80 MCM capacity) which serves irrigation purposes in the Jordan Valley. However, the dam suffers from accelerated annual sedimentation. Therefore, this study is directed to assess the erosion risk over the watershed, and to simulate actual annual sediment yield at the dam in order to devise the appropriate conservation practices. Generalized assessment was first conducted over the watershed on the basis of drainage texture, rainfall erosion index (R), and the ratio p2/P. As a result, the watershed is divided into zones of severe, high (gullying), high (overland flow) and low erosion risk. Sediment yield at the dam was evaluated by a simulation model. For model validation the simulation results were compared to the measured values over 12 years period, and a good agreement was obtained in some of the years. The simulation results allow us to assess the application of two practical conservation practices: terracing and plantation of trees. Received: 18 November 1997 · Accepted: 18 May 1998  相似文献   

14.
Artificial neural networks (ANNs) are used by hydrologists and engineers to forecast flows at the outlet of a watershed. They are employed in particular where hydrological data are limited. Despite these developments, practitioners still prefer conventional hydrological models. This study applied the standard conceptual HEC-HMS’s soil moisture accounting (SMA) algorithm and the multi layer perceptron (MLP) for forecasting daily outflows at the outlet of Khosrow Shirin watershed in Iran. The MLP [optimized with the scaled conjugate gradient] used the logistic and tangent sigmoid activation functions resulting into 12 ANNs. The R 2 and RMSE values for the best trained MPLs using the tangent and logistic sigmoid transfer function were 0.87, 1.875 m3 s?1 and 0.81, 2.297 m3 s?1, respectively. The results showed that MLPs optimized with the tangent sigmoid predicted peak flows and annual flood volumes more accurately than the HEC-HMS model with the SMA algorithm, with R 2 and RMSE values equal to 0.87, 0.84 and 1.875 and 2.1 m3 s?1, respectively. Also, an MLP is easier to develop due to using a simple trial and error procedure. Practitioners of hydrologic modeling and flood flow forecasting may consider this study as an example of the capability of the ANN for real world flow forecasting.  相似文献   

15.
Increasing water demands,especially in arid and semi-arid regions,continuously exacerbate groundwater as the only reliable water resources in these regions.Samalqan watershed,Iran,is a groundwater-based irrigation watershed,so that increased aquifer extraction,has caused serious groundwater depletion.So that the catchment consists of surface water,the management of these resources is essential in order to increase the groundwater recharge.Due to the existence of rivers,the low thickness of the alluvial sediments,groundwater level fluctuations and high uncertainty in the calculation of hydrodynamic coefficients in the watershed,the SWAT and MODFLOW models were used to assess the impact of irrigation return flow on groundwater recharge and the hydrological components of the basin.For this purpose,the irrigation operation tool in the SWAT model was utilized to determine the fixed amounts and time of irrigation for each HRU(Hydrological Response Unit)on the specified day.Since the study area has pressing challenges related to water deficit and sparsely gauged,therefore,this investigation looks actual for regional scale analysis.Model evaluation criteria,RMSE and NRMSE for the simulated groundwater level were 1.8 m and 1.1%respectively.Also,the simulation of surface water flow at the basin outlet,provided satisfactory prediction(R2=0.92,NSE=0.85).Results showed that,the irrigation has affected the surface and groundwater interactions in the watershed,where agriculture heavily depends on irrigation.Annually 11.64 Mm3 water entered to the aquifer by surface recharge(precipitation,irrigation),transmission loss from river and recharge wells 5.8 Mm3 and ground water boundary flow(annually 20.5 Mm3).Water output in the watershed included ground water extraction and groundwater return flow(annually 46.4 Mm3)and ground water boundary flow(annually 0.68 Mm3).Overally,the groundwater storage has decreased by 9.14 Mm3 annually in Samalqan aquifer.This method can be applied to simulate the effects of surface water fluxes to groundwater recharge and river-aquifer interaction for areas with stressed aquifers where interaction between surface and groundwater cannot be easily assessed.  相似文献   

16.
With a capacity of 86 MCM, King Talal Reservoir is considered a major water supply in Jordan. It was built exclusively to irrigate the land in the Jordan Valley. Unexpectedly, the design capacity of the reservoir was confronted by the elevated sediment inflows during and after the construction of the Irbid–Amman Highway in 1987. Since then the annual sediment inflow measured at the mouth of the reservoir was higher than expected in a similar year. Notably, the over-wet season of 1991/2, as a result of six major landslides along the highway, registered the highest sediment inflow into the reservoir. In the present work the fractional contribution of these landslides to total sediment yield at the reservoir was evaluated. The evaluation was made by applying the well-known erosion model, AGNPS (Young et al., USDA Conservation Research Report 35, 1987). To calibrate the model, it was successively applied from 1980/1 to 1990/1 on the measured sediment data before the occurrence of landslides. With a slight tune-up of some of the King Talal watershed erosion variables, fairly good agreement was obtained in some years. However, the disagreement noticed in other years might be attributed to some conservation measures practised in the watershed. Because the serious landslides occurred in the wet season of 1991/2, the model was run for the two scenarios in this year: with and without landslides. The difference in results represents the contribution of landslides to sediment yield at the reservoir. It is concluded, based on these results, that landslides, if continued without control, will definitely jeopardize the design capacity of the reservoir.  相似文献   

17.
This paper focuses on artificial groundwater recharge study in Ayyar basin, Tamil Nadu, India. The basin is covered by hard crystalline rock and overall has poor groundwater conditions. Hence, an artificial recharge study was carried out in this region through a project sponsored by Tamil Nadu State Council for Science and Technology. The Indian Remote Sensing satellite 1A Linear Imaging Self Scanning Sensor II (IRS 1A LISS II) satellite imagery, aerial photographs and geophysical resistivity data were used to prioritize suitable sites for artificial recharge and to estimate the volume of aquifer dimension available to recharge. The runoff water available for artificial recharge in the basin is estimated through Soil Conservation Service curve number method. The land use/land cover, hydrological soil group and storm rainfall data in different watershed areas were used to calculate the runoff in the watersheds. The weighted curve number for each watershed is obtained through spatial intersection of land use/land cover and hydrological soil group through GeoMedia 3.0 Professional GIS software. Artificial recharge planning was derived on the basis of availability of runoff, aquifer dimension, priority areas and water table conditions in different watersheds in the basin.  相似文献   

18.
Population growth, urbanization, and intensified agriculture have resulted in mobilization of nitrogen and phosphorus, which is the main cause of river water quality deterioration. Environmental regulation has expedited the necessity for agricultural producers to design and implement more environmentally suitable practices. Therefore, there is a need to identify critical nutrients and their loss/transport potential. Watershed model can be used to better understand the relationship between land use activities/management and hydrologic processes/water quality changes that occur within a watershed. The objective of the study is to test the performance of the SWAT model and the feasibility of using this model as a simulator of water flow and nitrogen and phosphorus yields over the Dongjiang River basin in South China. Spatial data layers of land slope, soil type, and land use were combined with geographic information system (GIS) to aid in creating model inputs. The observed streamflow and sediment at Boluo station in the Dongjiang River basin were used to calibrate and validate the model. Time series plots and statistical measures were used to verify model predictions. Predicted values generally matched well with the observed values during calibration and validation (R 2≥0.6 and Nash-Suttcliffe Efficiency ≥0.5) except for underestimation of sediment peaks and overestimation of sediment valleys at Boluo. This study shows that SWAT is able to predict streamflow, sediment generation, and nutrients transport with satisfactory results.  相似文献   

19.
中国西北高山、 高原广泛分布着冻土和积雪, 春季融雪和冻土融化是该地区重要的水文过程.基于模块化的寒区水文建模环境CRHM, 根据流域水文过程特征和观测数据约束, 选取描述不同寒区子水文过程的模块构建寒区水文模型, 并基于长期观测的两个典型寒区小流域来验证模块化的寒区水文模型.在冰沟流域, 主要模拟雪的积累/消融、 雪的升华、 融雪下渗和融雪径流过程. 结果显示: 冰沟流域积雪升华占降雪量(145.5 cm)的48%, 其中风吹雪引起的升华损失量(35 cm)占积雪升华(69 cm)的一半, 风速和辐射引起的积雪升华是该地区积雪物质平衡的重要组成; 构建的寒区水文模型可以再现春季积雪消融引起的径流过程.在左冒孔冻土流域, 主要模拟冻土下渗过程、 冻土坡面产流过程和土壤冻融对径流的影响. 结果显示: 构建的寒区水文模型可以捕捉到春季主要的冻土融化径流过程.两个流域的验证结果揭示: 模块化的建模方法在搭建模型结构的时候减少了模型的不确定性, 所以在未经率定的情况下, 具有在无资料和资料缺少地区模拟寒区水文要素和水文过程的能力.  相似文献   

20.
The Asna river basin is located in Hingoli and Nanded districts of Marathwada region of Maharashtra. A geomorphometric analysis is an important method for the investigation and management of natural resources of watershed. The geomorphometric analysis of Asna river basin classifies three sub-basins that have been delineated using GIS and remote sensing through measurements of linear, aerial, and relief aspects. The Asna river basin comprises an area of 1187 km2 with seventh-order drainage pattern. As per Strahler classification, the upper part of the basin shows dendritic to sub-dendritic and the lower part exhibits parallel to sub-parallel drainage pattern. The total numbers of stream segments are 2422 and length of streams is 2187.92 km. The bifurcation value ranges from 1.26 to 5.58 indicating that there are no structural disturbances. The form factor value (0.49) indicates that the shape of the basin is moderately circular. The high values of drainage density, stream frequency, and low infiltration number indicate the high runoff due to impermeable lithology. The slope of the basin varies from 1 to 32.2%, terrain elevation ranges from 333 to 551 m, and overall relief of the basin is 218 m amsl. River sub-basin prioritization has an immense importance in natural resource management, especially in semi-arid regions. The present study is an attempt to prioritize the sub-basins of Asna river based on geomorphometric parameters. The weightage is assigned to different morphometric parameters of sub-basins based on erosion potential. The Asna river sub-basins have been classified into three categories as high, medium, and low on the basis of priorities for soil and water conservation. It is confirmed that sub-basin I is characterized as highly vulnerable to erosion and has high sedimentation load; sub-basin II has low priority, i.e., very low erodibility; and sub-basin III is of moderate type. The morphometric analysis and prioritization methods can be applied to hydrological studies in surface as well as subsurface water, climatic studies, rainwater harvesting, groundwater recharging sites, and watershed management.  相似文献   

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