BUCKET模型在降雨径流预报中的应用

BUCKET模型结构简单,原理明确,参数较少,在澳大利亚和新西兰等国家得到了广泛的应用.在介绍模型结构和原理的基础上,为进一步拓宽模型的应用,将其应用于具有遥测资料的伊河流域,对陆浑水库入库旬平均流量过程进行了模拟.结果表明,模型与实测拟合精度较高,能够较好地反映伊河流域以旬为时间尺度的水文过程.将它与新安江三水源模型从原理、结构以及在栾川水文站的应用情况进行了比较,结果表明,率定期和检验期两个模型精度相当.因此,将BUCKET模型应用于陆浑水库入库径流预报中,可以为该水库的预报调度提供可靠的依据.     

BUCKET模型在降雨径流预报中的应用

BUCKET模型结构简单,原理明确,参数较少,在澳大利亚和新西兰等国家得到了广泛的应用。在介绍模型结构和原理的基础上,为进一步拓宽模型的应用,将其应用于具有遥测资料的伊河流域,对陆浑水库入库旬平均流量过程进行了模拟。结果表明,模型与实测拟合精度较高,能够较好地反映伊河流域以旬为时间尺度的水文过程。将它与新安江三水源模型从原理、结构以及在栾川水文站的应用情况进行了比较,结果表明,率定期和检验期两个模型精度相当。因此,将BUCKET模型应用于陆浑水库入库径流预报中,可以为该水库的预报调度提供可靠的依据。     

Solving Complex Rainfall-Runoff Processes in Semi-Arid Regions Using Hybrid Heuristic Model

In the current research, a hybrid model was proposed to solve the complexity of rainfall-runoff models in semi-arid regions. The proposed hybrid model structure consists of linking two data mining models, namely, Group Method of Data Handling (GMDH) and Generalized Linear Model (GLM). The proposed hybrid model structure consists of two phases. The GMDH model was used in the first phase of the hybrid model to predict daily streamflow. The first phase consists of two sections. In the first section a predictive model is developed using the time series of the daily streamflow. In the second section the rainfall-runoff model was developed. The outputs of the first phase of the hybrid model are used as inputs to the second phase of the hybrid model. The second phase of the hybrid model was developed using the GLM model. The Gomel River in Iraq was selected as a case study. The daily rainfall data and daily streamflow data for the period from January 1, 2004 to December 19, 2016 were used to train and validate the model. The results proved the accuracy of the proposed hybrid model in estimating the daily streamflow of the study area, where the value of R² was 0.92 in the training period and 0.88 in the validation period of the model.

     

海河流域平原区降雨产流模型研究

通过对海河流域平原区降雨产流机理进行研究,得出耕地灌溉率提高、地下水埋深增加是影响平原区产流的主要下垫面要素.根据下垫面要素的变化特点,建立了模拟地下水埋深变化和灌溉耕地产流特点的蓄满-超渗产流水文模型.并通过在海河平原的大清河山前平原、大清河中部平原、黑龙港中部平原3个类型区7个田块的灌溉入渗实验,分析给出了产流模型的重要参数——耕作层下层稳定入渗率.模型在牤牛河等7个典型流域进行应用,均得到较高的模拟精度.     

太行山区典型小流域降雨产流特征分析

以太行山区崇陵小流域为研究区域,采用1959—1967年、1985—2008年历史实测降雨产流资料,分析了研究区降雨特征及产流过程响应特征,并对比了不同时期降雨径流变化。结果表明:1研究区6—9月降雨以小雨为主,产流主要由暴雨和大雨控制;2产流机制以超渗产流为主,在前期湿润条件下,长历时低强度降雨也会造成蓄满产流;3与1959—1967年相比,1985—2008年的暴雨、大雨、中雨雨日分别减少26.1%、25.0%和12.4%,年径流系数减小80%,且降雨径流相关性减弱,说明人类活动成为影响径流量的重要因素。     

Comparison of Rainfall-Runoff Relationship Modeling using Different Methods in a Forested Watershed

The daily rainfall-runoff relationship in an experimental watershed was modeled using a statistical method and an artificial neural network method. The estimations were examined and a performance evaluation was done. It was seen that the ANN method, FFBP (Feed Forward Back Propagation), provided closer flow estimations reproducing the shape of the observed hydrograph more realistic. The superiority of FFBP was reflected in the performance evaluation criteria. The extreme flows, i.e., high and low flows, were relatively better approximated by FFBP indicating its promise as a useful tool for hydrologic studies such as flood modeling. The Rational Method was also used, as a conventional tool, to predict the maximum discharge for selected return periods. It was found to be realistic for the forested watershed under consideration when the C coefficient was taken as 0.20 for the 10-year period.

     

Influence of Time Step Synchronization on Urban Rainfall-Runoff Simulation in a Hybrid CPU/GPU 1D-2D Coupled Model

The 1D sewer - 2D surface coupled hydrodynamic model has increasingly become an essential tool for simulating and predicting the flood process and is widely used in the study of urban rainfall-runoff simulation. The current method of using the smaller time step of the sub model in the coupled model as the synchronization time greatly limits the computational efficiency, especially in the case of the large data amount or models executed in different platforms and in various types of codes. To evaluate the impact of time synchronization on the rainfall-runoff process in a coupled hydrodynamic model, a new model that couples the 2D GPU accelerated shallow water model and the 1D SWMM is applied to two urban catchments to simulate the rainfall-runoff-drainage processes, the fixed time step (5 s, 10 s, 30 s, 60 s, 120 s, 180 s and 300 s) is adopted to ensure the calculation efficiency and precision of the model. The results show that the time computational efficiency can be improved by 7.27%–27.37% in different scenarios compared with the method applying 2D model time step as the synchronization time; the surface runoff process is hardly affected as the synchronization time changes; and the relative error of the drainage process is less than 2.5% when the synchronization time is less than 60 s. Therefore, the fixed synchronization time method is recommended in the 1D-2D coupled model to improve the computational efficiency for flood and inundation simulation. Based on the advantage that the fixed synchronization time is easy to realize in the programming of the model and the high efficiency of the fixed synchronization time method concluded above, this work is expected to provide a reference for model coupling applications.

     

Application of a Hydrologic Model Considering Rainwater Storage to Analyze Storm-induced Landslides in a Forest Catchment

In this study, a conceptual hydrologic model was applied for the analysis of storm-induced landslides, which were affected by typhoons in 2004, in the forest catchments of Ehime Prefecture, Japan. Through the model, hydrologic conditions such as rainfall intensity, rainwater storage, and soil moisture behavior in 2004 were obtained and compared with other 19 years (1985 ∼ 2003). Furthermore, the relationship between landslide occurrence and hydrologic phenomena in the catchments were assessed. Results of this study indicated that soil moisture, excess rainfall storage combined with rainfall intensity, and its duration in the forest were the key elements for the occurrence of landslides. The hydrologic model in this study was able to represent hydrologic phenomena reasonably and it can be used for the estimation of discharge, soil moisture content, and water storage in catchments. The concept of this model is available to be applied in other areas and can be expected to provide important information on soil moisture behavior for forecasting and preventing landslide disasters.     

考虑井筒储存与表皮效应影响的脉冲试井理论模型

脉冲试井用来确定油藏的传导系数和储存能力,通过改变激动并(脉冲井)的产量并在附近观察井(响应井)上观察压力响应来进行脉冲试井。 本文给出考虑井筒储存和井壁的表皮效应的脉冲试井理论模型。以往研究多采用切线法,这种方法局限性很大,常给解释结果带来误差。本文引入割线法,可以在压力曲线的任一位置做平行线时,明显提高了解释精度。     

Water Resources Allocation in Transboundary River Basins Based on a Game Model Considering Inflow Forecasting Errors

Dynamic transboundary water resources allocation based on inflow prediction results is an important task for water resources management in river basins. This paper takes the watershed management agency as the leader and the associated area as the follower, and proposes a two-level asymmetric Nash-Harsanyi Leader-Follower game model considering inflow forecasting errors. In the proposed model, the Monte Carlo method is used to analyze the uncertainty of various stakeholder allocation results and the response regularity to the total water resource uncertainty. The quantitative relationship between the allocation results of stakeholders and the mean and standard deviation of total water resource uncertainty is subsequently established. The Huaihe River basin in China is selected as a case study. The results show the following: (1) the water allocated to the watershed management agency and three provinces has a normal distribution when the inflow forecasting error obeys the normal distribution; (2) the sum of the mean of the water allocated to stakeholders equals the mean of the forecast water resource and the sum of the standard deviations of the water allocated to stakeholders equals the standard deviation of the forecast water resource; (3) the mean and standard deviation of the allocation results have a good linear relationship with the mean and standard deviation of forecast water resource; (4) the distribution parameters of the stakeholder allocation results can be directly derived from the distribution parameters of the forecast information, thus aiding the stakeholders in making decisions and improving the practical value of the method.

     

Long-Term Scheduling of Cascade Reservoirs Considering Inflow Forecasting Uncertainty Based on a Disaggregation Model

Water Resources Management - Forecasted inflow is one of the most important input information for reservoir operation planning. However, current inflow prediction accuracy is difficult to meet the...     

Finite Element Method and GIS Based Distributed Model for Soil Erosion and Sediment Yield in a Watershed

The objective of this study is to develop a soil erosion and sediment yield model based on the kinematic wave approximation using the finite element method, remote sensing and geographical information system (GIS) for calculating the soil erosion and sediment yield in a watershed. Detachment of soil particles by overland flow occurs when the shear stress at the surface overcomes the gravitational forces and cohesive forces on the particles. Deposition occurs when the sediment load is greater than the transport capacity. Beasley et al.’s (Trans ASAE 23:938–944, 1980) transport equations for laminar and turbulent flow conditions are used to calculate the transport capacity. The model is capable of handling distributed information about land use, slope, soil and Manning’s roughness. The model is applied to the Catsop watershed in the Netherlands and the Harsul watershed in India. Remotely sensed data has been used to extract land use/land cover map of the Harsul watershed, and other thematic maps are generated using the GIS. The simulated results for both calibration and validation events are compared with the observed data for the watersheds and found to be reasonable. Statistical evaluation of model performance has been carried out. Further, a sensitivity analysis has also been carried out to study the effect of variation in model parameter values on computed volume of sediment, peak sediment and the time to peak sediment. Sensitivity analysis has also been carried out for grid size variation and time step variation of the Catsop watershed. The proposed model is useful in predicting the hydrographs and sedigraphs in the agricultural watersheds.     

Reservoir Management Using a Network Flow Optimization Model Considering Quadratic Convex Cost Functions on Arcs

The allocation of water resources between different users is a hard task for water managers because they must deal with conflicting objectives. The main objective is to obtain the most accurate distribution of the resource and the associated circulating flows through the system. This induces the need for a river basin optimization model that provides optimized results. This article presents a network flow optimization model to solve the water allocation problem in water resource systems. Managing a water system consists in providing water in the right proportion, at the right place and at the right time. Time expanded network allows to take into consideration the temporal dimension in the decision making. Since linear cost functions on arcs present many limitations and are not realistic, quadratic convex cost functions on arcs are considered here. The optimization algorithm developed herein extend the cycle canceling algorithm developed for linear cost functions. The methodology is applied to manage the three reservoirs of La Haute-Vilaine’s watershed located in the north west of France to protect a three vulnerable areas from flooding. The results obtained with the algorithm are compared to a reference scenario which consists in considering reservoirs transparent. The results show that the algorithm succeeds in managing the reservoir releases efficiently and keeps the flow rates below the vigilance flow in the vulnerable areas.     

沟坡重力侵蚀的定量观测方法

重力侵蚀的定量观测是沟坡侵蚀产沙研究中亟待突破的"瓶颈"问题。采用MX-2010-G型地貌仪实时监测降雨模拟试验中沟坡地形的动态变化,并在ArcGIS软件中赋值形成三维立体图,进而可提供坡体的体积、投影面积和各点坐标等参数;重力侵蚀发生前、后瞬间坡体的体积差,就是该次重力侵蚀量。然后,对观测仪器和方法进行率定和验证:①采用常规观测方法以及地貌仪观测方法,测量同一坡体的体积,以验证地貌仪的精确性;②采用地貌仪观测沟坡重力侵蚀试验过程中历次重力侵蚀量,并将其与试验过程进行对比分析,以验证观测结果的合理性;③任取3次试验过程数据,分别让两组不同试验人员进行重力侵蚀事件筛选和处理,比较2组处理结果的差异,以验证数据处理方法的可靠性。试验结果表明:①对于5组不同坡度、体积约为24 000 cm3的沟坡模型,地貌仪测量的体积相对误差可以控制在±10%以内,其中绝对值最大相对误差为9.0%,绝对值最小误差为0.4%;②地貌仪测量到的重力侵蚀量变化过程与试验中直观观测记录的侵蚀现象基本一致;③对于同一沟坡侵蚀过程,两组数据处理的重力侵蚀量相对误差都在10%以内。综合分析表明,该观测仪器和观测方法能够对模拟降雨中沟坡重力侵蚀进行较准确的定量观测。     

临汾闸坝蓄水工程河工模型冲刷试验研究

通过室内模型测定了临汾闸坝蓄水工程的冲淤情况,对工程提出了防冲措施及建议,为工程安全运行提供了依据。     

我国流域土壤侵蚀预报模型研究动态评述

流域尺度土壤侵蚀预报模型的研究对流域水土保持规划、国土利用和水土流失的治理十分重要。我国流域土壤侵蚀经验统计模型有：皇甫川流域、黄土高原多沙粗沙区、陕北地区、三峡库区、长江中上游小流域模型等。通过对土壤侵蚀模型的研究，可建立一套土壤侵蚀动力学体系和适合我国国情的预报模型。     

Coupling Surface Water and Groundwater Flows in a Laboratory Model Using Foam as Artificial Groundwater Material

A laboratory mock-up of a surface water groundwater system with foam blocks used to replicate a groundwater material was mounted in a tidal basin in the Hydraulics Laboratory at Cardiff University, UK. River flow in the form of a channel was generated, with an oscillating weir at the lower boundary of the system producing tides or controlled water levels. The purpose of the experiment was to investigate the manner in which flow and a conservative tracer interacted between surface and sub-surface flows for simulated riverine and tidal conditions. In these controlled laboratory conditions, results obtained with respect to flows were consistent with the laws governing surface-subsurface flows. In contrast, the conservative tracer could not move through the foam for any meaningful results to be obtained, which was thought to be due to the dominance of surface tension and sorption in the foam pores.     

Avulsions in a Simulated Large Lowland Braided River

The understanding of the complicated braiding mechanisms in braided rivers is closely related to avulsions. They control the channel generation, migration and disappearance in large lowland braided rivers, and are considered to be the key factor that keeps the river maintaining a dynamic braided pattern. However, their occurring processes and mechanisms are still not well understood due to the lack of detailed measurements with sufficient temporal and spatial data covering multiple bifurcations. In the present study, a numerical model based on the physical process of hydrodynamics and sediment transport is used to simulate the suspended sediment transport and river channel evolution in braided rivers. The model predicted braiding processes are comparable to those observed in nature. Efforts are made to investigate the morphological processes that are key for river braiding. Three types of avulsions observed in natural rivers have been identified in the model predicted river and their evolution processes and controlling factors are examined based on the predicted flow velocity, sediment concentration, bed elevation and sediment size distribution. It was found that, a curving channel bend is the key factor in introducing a constriction avulsion, while the choking avulsion and apex avulsion are controlled by the water surface slope and bed elevation. They are mostly affected by the upstream channel pattern changes.     

WEPP在天镇县大梁沟流域土壤侵蚀预报中的应用研究

利用WEPP模型对山西大同天镇县大梁沟流域进行土壤侵蚀预报,目的是研究WEPP模型是否适用于黄土高原地区的土壤侵蚀预报,研究结果将有助于黄土高原地区土壤侵蚀预报的改进和拓展.