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1.
Hydrological models within inflow forecasting systems for high-alpine hydropower reservoirs can provide valuable information as part of a decision support system for the improvement of hydropower production or flood retention. The information, especially concerning runoff, is however rarely available for the calibration of the hydrological models used. Therefore, a method is presented to derive local runoff from secondary information for the calibration of the model parameters of the rainfallrunoff model COSERO. Changes in water levels in reservoirs, reservoir outflows, discharge measurements at water intakes and in transport lines are thereby used to derive the local, “natural” flow for a given sub-catchment. The proposed method is applied within a research study for the ÖBB Infrastructure Railsystem division in the Stubache catchment in the central Austrian Alps. Here, the ÖBB operates the hydropower scheme “Kraftwerksgruppe Stubachtal”, which consists of 7 reservoirs and 4 hydropower stations. The hydrological model has been set up considering this human influences and the high natural heterogeneity in topography and land cover, including glaciers. Overall, the hydrological model performs mostly well for the catchment with highest NSE values of 0.78 for the calibration and 0.79 for the validation period, also considering the use of homogeneous parameter fields and the uncertainty of the derived local discharge values. The derived runoff data proved to be useful information for the model calibration. Further analysis, examining the water balance and its components as well as snow cover, showed satisfactory simulation results. In conclusion, a unique runoff dataset for a small scale high-alpine catchment has been created to establish a hydrological flow prediction model which in a further step can be used for improved and sustainable hydropower management.  相似文献   

2.
A hydrologic model consists of several parameters which are usually calibrated based on observed hydrologic processes. Due to the uncertainty of the hydrologic processes, model parameters are also uncertain, which further leads to the uncertainty of forecast results of a hydrologic model. Working with the Bayesian Forecasting System (BFS), Markov Chain Monte Carlo simulation based Adaptive Metropolis method (AM-MCMC) was used to study parameter uncertainty of Nash model, while the probabilistic flood forecasting was made with the simulated samples of parameters of Nash model. The results of a case study shows that the AM-MCMC based on BFS proposed in this paper is suitable to obtain the posterior distribution of the parameters of Nash model according to the known information of the parameters. The use of Nash model and AM-MCMC based on BFS was able to make the probabilistic flood forecast as well as to find the mean and variance of flood discharge, which may be useful to estimate the risk of flood control decision.  相似文献   

3.
Using field hydrological data, the relationship between the mixing of salt water and fresh water and the tidal range/ high tidal level in the Changjiang (Yangtze) River estuary is discussed, and the transporting and concentrating of suspended sediment in the estuary were also analysed in respect to the circulation, flocculation and stratified interface resulting from mixing.The calculation results by two-dimentional box model have confirmed the effects of the circulation on the concentrating of suspended sediment in the estuary. The conclusions derived from this work have deepened the understanding on the mixing in the Changjiang River estuary and are of significance in bo'th theory and practice.  相似文献   

4.
洪水研究包括径流与淹没两种模式。为了探究流域降雨产汇流与淹没情况、提高洪水预报精度,本研究在传统流域水文模型的基础上耦合二维水动力学模型,建立水文-水动力耦合模型。以我国吉林温德河流域为研究实例,模拟了2017年“7·13”洪水在下游口前镇所处子流域洪水淹没过程。首先对基础数据进行预处理,建立HEC-HMS水文模型并进行参数优化后,最终获得流量过程水文结果作为水动力学模型边界条件,之后建立HEC-RAS二维水动力学模型对重要子流域进行淹没模拟。耦合模型计算结果显示,水文模型经多参数优化流量模拟的NSE系数为0.988,水动力计算最大淹没水深达9.3 m相对误差为-5.2%。从泛洪模拟结果来看,子流域上游部分的农田大量被淹,淹没水深范围在0.5~2.0 m,平均流速基本在1 m/s以下。下游口前镇内最大淹没水深接近1 m,水流速度0.2 m/s至1.5 m/s,与实际的淹没情况相吻合。研究表明,所建水文水动力耦合模型模拟计算的结果准确率较高,对具有复杂水文、水力条件的流域的洪水预报具有重要的指导意义。  相似文献   

5.
针对川中丘陵区紫色土坡耕地严重水土流失,选取典型代表李子溪流域为研究区,构建了其SWAT的模型数据库,包括地形、土壤、气象和土地利用数据库。并利用赵家祠水文站1970-1979年的实测径流和泥沙资料,对该流域的SWAT模型参数进行率定再采用1980-1986年的实测资料,对模型的适用性进行验证,同时用相对误差Re和Nash确定性系数Ens评价模拟效果。结果显示,径流和泥沙模拟相对误差均在±15%范围以内,Nash确定性系数均大于等于0.70,说明SWAT模型对李子溪流域年、月径流和年泥沙量的模拟精度较高。同时模拟值与实测值和降雨量的变化趋于一致。可见,用SWAT模型模拟和预测雨量较为丰沛、土壤侵蚀较严重的紫色丘陵地区的产流产沙是实用、可行的。  相似文献   

6.
基于WebGIS的流域级洪水管理系统集成与应用   总被引：1，自引：0，他引：1  
流域级洪水管理系统指为流域机构服务的洪水管理系统,是基于计算机网络、地理信息系统、数据库技术,专业分析模型,采用人机交互方式,按照统一标准与规范建立的流域洪水管理平台。为洪水预报、预警、预案编制、应急调度、风险评价、洪水整治、决策会商提供先进技术手段。本文首先讨论了流域洪水管理系统的结构设计与数据库,然后,以松花江流域洪水管理系统为例,对系统功能与分析模型进行了讨论。功能模块包括基础信息管理、洪水监视预警、洪水预报调度、二维洪水仿真、灾情评估、防汛管理等功能模块;分析模型方面,建立了水文-水力学耦合模型、全流域洪水预报模型与洪水调度模型。该模型由基于MIKE NAM的全流域降雨径流模型与基于MIKE11 HD的嫩江、二松、松干河道一维水动力模型组成。此外,在哈尔滨等4个重点城市与两个蓄滞洪区构建了MIKE21的二维洪水模拟模型,在城市、蓄滞洪区与防洪重点保护区,建立了灾情影响分析模型等。最后,利用WebGIS技术对这些功能模块进行了集成,建立了功能齐全的松花江流域洪水管理系统。作为国内第一个流域级洪水管理系统,松花江流域洪水管理系统的设计与建设,对流域级洪水管理系统的研究进行了有益的探索。  相似文献   

7.
The spatial distribution of soil physical properties is essential for modeling and understanding hydrological processes. In this study, the different spatial information (the conventional soil types map-based spatial information (STMB) versus refined spatial information map (RSIM)) of soil physical properties, including field capacity, soil porosity and saturated hydraulic conductivity are used respectively as input data for Water Flow Model for Lake Catchment (WATLAC) to determine their effectiveness in simulating hydrological processes and to expound the effects on model performance in terms of estimating groundwater recharge, soil evaporation, runoff generation as well as partitioning of surface and subsurface water flow. The results show that: 1) the simulated stream flow hydrographs based on the STMB and RSIM soil data reproduce the observed hydrographs well. There is no significant increase in model accuracy as more precise soil physical properties information being used, but WATLAC model using the RSIM soil data could predict more runoff volume and reduce the relative runoff depth errors; 2) the groundwater recharges have a consistent trend for both cases, while the STMB soil data tend to produce higher groundwater recharges than the RSIM soil data. In addition, the spatial distribution of annual groundwater recharge is significantly affected by the spatial distribution of soil physical properties; 3) the soil evaporation simulated using the STMB and RSIM soil data are similar to each other, and the spatial distribution patterns are also insensitive to the spatial information of soil physical properties; and 4) although the different spatial information of soil physical properties does not cause apparent difference in overall stream flow, the partitioning of surface and subsurface water flow is distinct. The implications of this study are that the refined spatial information of soil physical properties does not necessarily contribute to a more accurate prediction of stream flow, and the selection of appropriate soil physical property data needs to consider the scale of watersheds and the level of accuracy required.  相似文献   

8.
On the basis of the observational data on the annual sediment transport by debris flow in recent 8 years, appling the catastrophe forecast method of Grey System Theory, this study has established the catastrophe model of the annual sediment transport by debris flow in Jiangjia Gully. It has forecasted the next potential catastrophic year in which the annual sediment transport will be over the catastrophic. threshold 2 million m3. Furthermore, it has introduced the "equal dimension-new information model", which makes the forecast be done continuously.  相似文献   

9.
地基是工程建设的基础,其承载力计算和预测十分关键,决定着建筑工程上部结构的安全性与稳定性。为实现小数据量、短周期、较高精度的地基承载力预测。本研究提出以地基静载试验数据为依据,利用灰色模型进行计算,结合马尔科夫优化,建立灰色马尔科夫预测模型,预测固定荷载作用下的地基沉降,进而明确相应沉降下的基地承载力。同时,将该模型与传统的灰色GM(1, 1)模型、指数曲线拟合模型进行对比,分析3种模型的优劣。结果表明,案例一中,静载试验下的地基承载能力完好,灰色马尔科夫模型、GM(1, 1)模型、指数曲线模型预测值与实测值的平均相对误差依次为1.55%,3.80%,10.22%,灰色马尔科夫模型精度最高,更契合地基静载试验,能准确有效地明确地基承载力;案例二中,地基在静载试验下发生破坏,破坏前灰色马尔科夫模型预测值与实测值的平均相对误差仅为0.5%,预测效果良好。破坏时,地基沉降迅速增加,加载点模型预测值与实测值的相对误差出现异常,骤增至26.29%,以此可判断破坏前一级加载序列荷载为该地基的极限承载力。运用此模型指导地基静载试验,在保障工程施工安全的前提下,相邻试验点可以适当减少静载试验次数,节约工程施工成本,为信息化地基静载试验提供一个新的计算工具。   相似文献   

10.
根据长三角地区7个探空站基于积分法计算的2016年大气水汽转换系数（K值）,利用多元线性拟合分别构建不顾及高程的Emardson-I精化模型和顾及高程的Emardson-H精化模型,并用2017年的K值验证两种模型的精度。实验结果表明,Emardson-H预报模型的MAE和RMS分别为0.001 297和0.001 616,略优于Emardson-I预报模型的0.001 303和0.001 620;基于两种新模型的GNSS-PWV反演精度相当,其MAE和RMS均优于0.6 mm。因此,Emardson-I模型以其无需实测气象参数和无需顾及高程在长三角地区的地基GNSS气象学实时应用中具有更好的效率优势。  相似文献   

11.
基于ArcView GIS平台,利用流域水资源规划管理软件工具MIKE BASIN,以西藏达孜县为试验区,采用50×50m格网DEM数据,开展拉萨河流域内的地表水的产汇计算,并进行流域水资源合理配置研究。本文建立了流域供需水的空间分析网络,对各汇流区进行流域模拟分析,研究结果以直观的专题图表显示,为本区的流域水资源管理提供了可视化的研究框架。  相似文献   

12.
The upper Huanghe(Yellow) River basin is situated in the northeast of the Qinghai-Xizang(Tibet)Plateau of China.The melt-water from the snow-cover is main water supply for the rivers in the region during springtime and other arid regions of the northwestern China, and the hydrological conditions of the rivers are directly controlled by the snowmelt water in spring .So snowmelt runoff forecast has importance for hydropower,flood prevention and water resources utilize-tion.The application of remote sensing and Geographic Information System(GIS) techniques in snow cover monitoring and snowmelt runoff calculation in the upper Huanghe River basin are introduced amply in this paper.The key parame-ter-snow cover area can be computed by satellite images from multi-platform,multi-templral and multi-spectral.A clus-ter of snow-cover data can be yielded by means of the classification filter method.Meanwhile GIS will provide relevant information for obtaining the parameters and also for zoning .According to the typical samples extracting snow covered moun-tained in detail also.The runoff snowmelt models based on the snow-cover data from NOAA images and observation data of runoff,precipitation and air temperature have been satisfactorily used for predicting the inflow to the Longyangxia Reser-voir,which is located at lower end of snow cover region and is one of the largest reservoirs on the upper Huanghe River, during late March to early June.The result shows that remote sensing techniques combined with the ground meteorological and hydrological observation is of great potential in snowmelt runoff forecasting for a large river basin.With the develop-ment of remote sensing technique and the progress of the interpretation method,the forecast accuracy of snowmelt runoff will be improved in the near future .Large scale extent and few stations are two objective reality situations in Chian,so they should be considered in simulation and forecast.Apart from dividing ,the derivation of snow cover area from satellite images would decide the results of calculating runoff.Field investigation for selection of the learning samples of different snow patterns is basis for the classification.  相似文献   

13.
Global reanalysis precipitation products could provide valuable meteorological information for flow forecasting in poorly gauged areas, helping to overcome a long-standing challenge in the field. But not all data sources are suitable for all regions or perform the same way in hydrological modeling, so it is essential to test the suitability of precipitation products before applying them. In this study, five widely used global high-resolution precipitation products—Asian Precipitation Highly Resolved Observational Data Integration Towards Evaluation of Water Resources(APHRODITE), National Centers for Environmental Prediction Climate Forecast System Reanalysis(NCEP-CFSR), Climate Hazards Group InfraRed Precipitation with Station Data(CHIRPS), China Gauge-based Daily Precipitation Analysis developed by China Meteorological Administration(CMA) and Agricultural Model Intercomparison and Improvement Project based on the NASA Modern-Era Retrospective Analysis for Research and Applications(AgMERRA)—were evaluated using statistical methods and a hydrological approach for their suitability for the Lancang River Basin. The results indicated that APHRODITE, CMA, AgMERRA and CHIRPS were more accurate precipitation indicators than NCEP-CFSR in terms of the multiyear average and seasonal spatial distribution pattern, all of the CHIRPS, Ag MERRA and APHRODITE perform better than CMA and NCEP-CFSR at the small, medium and high precipitation intensities ranges in subbasin11 and sunbabsin46. All five products performed better in subbasin46(a low-altitude region) than in subbasin11(a high-altitude region) on the daily and monthly scales. In addition to NCEP-CFSR, the other four products all presented encouraging potential for streamflow simulation at daily(Yunjinghong) and monthly(Yunjinghong, Jiuzhou and Gajiu) scale. Hydrological simulations forced with APHRODITE were the best of the five for the Yunjinghong station in capturing daily and monthly measured streamflow. Except for NCEP-CFSR, all products were very good for hydrological simulations for the Gajiu and Jiuzhou stations.  相似文献   

14.
山区降水较集中,但降水测站多位于山谷或人口密集区,代表性差。遥感和再分析降水产品能提供时空分布连续的数据,不受地形条件限制。柴达木盆地中心属干旱荒漠区,水是制约该区开发的首要条件,其四周属高寒山区,降水相对较多,但降水监测十分薄弱。为获取该区相对精确的降水时空分布信息,本文评估了4套高分辨率降水产品（CMADS、TRMM、GPM和MSWEP）的适用性。首先基于地面站点数据评估它们在不同时空尺度上的精度,并分析它们在柴达木盆地的空间分布和年内分配特征。然后,以盆地东南隅的无测站山区香日德河流域为研究区,利用降水产品驱动SWAT模型来评估它们的分布式水文模拟适用性。结果表明：(1) MSWEP在年、月尺度上与站点降水的吻合程度最高（R≥0.79,PBIAS=0.5%）,其次是GPM和TRMM,CMADS精度最低（R≥0.64,PBIAS=5.8%）;(2)从降水精度与站点高程的关系来看,降水产品在相对低海拔区容易高估站点降水,而在相对高海拔区常低估实际降水;(3)在香日德河流域,MSWEP(NSE=0.64)在基准期（2009—2012年）的径流模拟表现明显好于其它降水产品（NSE=0.3...  相似文献   

15.
Satellite-based products with high spatial and temporal resolution provide useful precipitation information for data-sparse or ungauged large-scale watersheds. In the Lower Lancang-Mekong River Basin, rainfall stations are sparse and unevenly distributed, and the transboundary characteristic makes the collection of precipitation data more difficult, which has restricted hydrological processes simulation. In this study, daily precipitation data from four datasets(gauge observations, inverse distance weighted(IDW) data, Tropical Rainfall Measuring Mission(TRMM) estimates, and Climate Hazards Group InfraRed Precipitation with Stations(CHIRPS) estimates), were applied to drive the Soil and Water Assessment Tool(SWAT) model, and then their capability for hydrological simulation in the Lower Lancang-Mekong River Basin were examined. TRMM and CHIRPS data showed good performances on precipitation estimation in the Lower Lancang-Mekong River Basin, with the better performance for TRMM product. The Nash-Sutcliffe efficiency(NSE) values of gauge, IDW, TRMM, and CHIRPS simulations during the calibration period were 0.87, 0.86, 0.95, and 0.93 for monthly flow, respectively, and those for daily flow were 0.75, 0.77, 0.86, and 0.84, respectively. TRMM and CHIRPS data were superior to rain gauge and IDW data for driving the hydrological model, and TRMM data produced the best simulation performance. Satellite-based precipitation estimates could be suitable data sources when simulating hydrological processes for large data-poor or ungauged watersheds, especially in international river basins for which precipitation observations are difficult to collect. CHIRPS data provide long precipitation time series from 1981 to near present and thus could be used as an alternative precipitation input for hydrological simulation, especially for the period without TRMM data. For satellite-based precipitation products, the differences in the occurrence frequencies and amounts of precipitation with different intensities would affect simulation results of water balance components, which should be comprehensively considered in water resources estimation and planning.  相似文献   

16.
于2008年5月(枯水期)和8月(丰水期),分别对黄河入海口潮间带大型底栖动物进行了野外调查与研究。结果表明,底栖动物生物量平均为177.23±55.56 g.m-2,软体动物占据绝对优势;各潮带丰水期底栖动物生物量较枯水期增加,且低潮带>中潮带>高潮带。底栖动物栖息密度平均为573.07±125.60 m-2,软体动物栖占据绝对优势,丰水期底栖动物栖息密度较枯水期升高。四角蛤蜊(Mactra veneriformis)、泥螺(Bullacta exarata)、双齿围沙蚕(Perinereis aibuhitensis)、彩虹明樱蛤(Moerella iridescens)、天津厚蟹(Helice tientsinensis)、青蛤(Cyclina sinensis)、豆形拳蟹(Philyra pisum)、光滑河蓝蛤(Potamocorbula laevis)、托氏昌螺(Umbonium thomasi)和短文蛤(Meretrix pethechialis)等种类的相对重要性指数值较高。  相似文献   

17.
针对传统降雨预测理论错报率高及算法拟合精度低等缺陷,将与降雨过程相关的多种气象参数(温度、相对湿度、露点温度、气压等)及时间参数(年积日和天积时)引入短临降雨预测模型的构建.将新加坡2个GNSS和气象并址的测站(NTUS、SNUS)2010?2012年的气象数据及降雨数据作为样本,研究气象参数与降雨数据的时变特征,结果...  相似文献   

18.
针对一阶预测有效度未能考虑预测精度的方差以及权数不变的问题,提出一种基于二阶预测有效度IOWGA算子的变权组合预测方法。该方法以二阶预测有效度作为目标函数,根据预测精度赋权,然后将其运用于变形数据分析中。实验结果表明,该模型预测精度高,适用于变形预测与分析。  相似文献   

19.
针对传统组合预测模型中各单项预测模型赋权问题的不足,提出一种基于Theil不等系数的IOWA算子最优变形组合预测模型。利用IOWA算子,依据各单项预测模型预测值各时间点精度的不同,赋予不同的权系数,建立最优组合预测模型,并将其应用于变形数据分析与预测。实验结果表明,本文方法的预测结果比各单项模型与传统组合模型的结果更准确。  相似文献   

20.
Daily meteorological data are the critical inputs for distributed hydrological and ecological models. This study modified mountain microclimate simulation model （MTCLIM） with the data from 19 weather stations, and compared and validated two methods （the MTCLIM and the modified MTCLIM） in the Qilian Mountains of Northwest China to estimate daily temperature （i.e., maximum temperature, minimum temperature） and precipitation at six weather stations from i January 2000 to 31December 2009. The algorithm of temperature in modified MTCLIM was improved by constructing the daily linear regression relationship between temperature and elevation, aspect and location information. There are two steps to modify the MTCLIM to predict daily precipitation： firstly, the linear regression relationship was built between annual average precipitation and elevation, location, and vegetation index; secondly, the distance weight for measuring the contribution of each weather station on target point was improved by average wind direction during the rainy season. Several regression analysis and goodness-of-fit indices （i.e., Pearson＇s correlation coefficient, coefficient of determination, mean absolute error, root-mean-square error and modelingefficiency） were used to validate these estimated values. The result showed that the modified MTCLIM had a better performance than the MTCLIM. Therefore, the modified MTCLIM was used to map daily meteorological data in the study area from 2000 to 2009. These results were validated using weather stations with short time data and the predicted accuracy was acceptable. The meteorological data mapped could become inputs for distributed hydrological and ecological models applied in the Qilian Mountains.  相似文献   

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