遥感和GIS支持下的平原河网区暴雨产流模型研究

分析了产流模型研究和应用现状及平原河网区产、汇流特点,提出了遥感、ＧＩＳ支持下的平原河网区暴雨产流模型。模型将下垫面因素和暴雨因素列为随时空变化而变化的因子,并用遥感技术实时获取雨前土壤含水量等可变的区域下垫面数据;从物理成因出发,建立了反映暴雨产流内在机理、适合实际应用的数学模型,使模型具有高度的适应性,并对全区各时空单元的产、汇流情况分别进行计算模拟,模型计算结果与实际情况较为相符。     

西北干旱半干旱地区设计净雨模型探讨

本文总结了甘肃、青海、宁夏、新疆四省区《暴雨径流查算图表》编制工作中设计净雨的推求方法,对本协作片采用的一种模型作了理论分析和实际检验。结果表明,本法符合降雨下渗、产流的物理概念,成果具有较好的精度,且简便易行,具有较大的实用价值。一、对现行方法的分析综述产流是暴雨洪水过程中的一个重要而复杂的环节;在干旱、半干旱地区,其复杂性尤为突出。降雨到达地面以后,首先要经过植物截     

平原湖区排涝水文计算问题研究

利用平原区径流实验资料,建立了总入流雨洪经验关系和按蓄洪产流模型法经参数识别后,建立产流参数与地理要素之间的关系,并应用产流规律研究了湖北省平原湖区的排涝水文计算问题,认为在目前站网条件下,一般具备直接面暴雨设计基础,不宜采用暴雨点面折算方法。对资料暂不满足计算要求的设计区域,提出了一种改进的“动点定面”关系,对特殊情况下的平原湖区的常遇频率暴雨设计,可以给出比较满意的成果。     

一个华南热带暴雨径流区的流域产流模型

在华南热带暴雨地区,雨强在时空上均有强烈变化,形成下渗过程的复杂多变性质。本文运用数值逼近方法,建立了一个下渗数值模型,并以该模型为核心,结合考虑本地区植被对产流过程的影响,提出了一个流域产流模型. 本文应用实测资料对模型进行了率定与检验.结果表明,所提出的模型能较好地模拟本地区的暴雨径流过程。     

对新安江模型的改进

在新安江模型的结构中增加了超渗产流模型,对新安江模型进行了改进,使得新安江模型的产流理论更加完善,可以用于湿润地区,半干旱半湿润地区及干旱地区。把改进后的模型在半干旱半湿润的沂沭泗流域进行了验证和应用。     

垂向混合产流模型及应用

半干旱地区的产流理论和计算方法研究，在我国尚进一个薄弱环节。据蓄满和超渗两种概化的产流机制，提出了垂向混合唱 产流模型。经应用检验，表明模型结构较合理，模拟拟实测资料的效果良好。     

新安江模型理论研究的进展与探讨

回顾了新安江模型发展的历程,指出在具有物理基础的分布式水文模型发展遭遇理论瓶颈的背景下,可重新审视新安江等概念性模型的重要作用和地位。文章介绍了近年来新安江模型在结构、理论方法及应用等方面取得的进展,认为新安江模型是一个不断发展的模型理论体系。新安江模型理论的创新首先需秉承其理论的特色,即蓄满产流及以统计曲线形式表达的部分产流的概念,可用山坡水文的理论和发现指导模型创新,并采取野外实验、理论分析与计算机建模三者并重的理念。     

对确定推理公式中损失参数μ值的建议

在由推理公式估算小流域设计洪水中,损失参数μ值的定量至关重要。与一般的产流问题相同,μ值的定量问题实质上是由暴雨推求净雨的扣损问题。扣损的精度直接影响设计值的准确程度。各地目前确定损失参数μ值的方法很多,但概括起来大致可分为以下两大类:     

季节冻土区地下水观测成果在流域产汇流理论研究中的应用述评

将山坡水文学产流机制——超渗地面径流、饱和地面径流、壤中径流和地下径流等成分的产流机制,概括为界面(不透水层)产流机制。介绍季节冻土区近地表地下水若干创新的观测成果,综述其在季节冻土区流域产汇流理论研究领域中的应用,建议水利、农业、气象、林业、地质等部门在季节冻土区近地表地下水观测方面通力合作。可以预期,季节冻土区近地表地下水观测成果在产汇流理论研究以及流域水文模型研制中得到进一步的应用。     

考虑风场影响的城市建筑区产流计算方法

风场作用下城市建筑物的遮挡作用直接影响区域产流过程,为提高城市雨洪模拟精度,需揭示风场作用下建筑区的独特产流机理并构建相应的计算方法。将建筑区的产流面划分为水平面和竖直面,基于计算流体力学理论求解降雨倾角,结合几何关系确定降雨在水平面和竖直面上的分布,通过产流理论分别计算2类产流面的产流,提出建筑区的产流计算方法,并将其耦合入SWMM模型在试验流域进行了验证。结果表明：(1)改动模型所模拟的径流的纳什效率系数整体高于原始SWMM模型,且洪峰模拟效果更好;(2)改动模型的土壤饱和导水率等关键参数取值更为合理;(3)改动模型对不同气象条件下建筑区产流模拟的稳定性更好。该方法可提高建筑区产流模拟精度。     

Flood frequency analysis based on simulated peak discharges

Flood frequency approaches vary from statistical methods, directly applied on the observed annual maximum flood series, to adopting rainfall–runoff simulation models that transform design rainfalls to flood discharges. Reliance on statistical flood frequency analysis depends on several factors such as the selected probability distribution function, estimation of the function parameters, possible outliers, and length of the observed flood series. Through adopting the simulation approach in this paper, watershed-average rainfalls of various occurrence probabilities were transformed into the corresponding peak discharges using a calibrated hydrological model. A Monte Carlo scheme was employed to consider the uncertainties involved in rainfall spatial patterns and antecedent soil moisture condition (AMC). For any given rainfall depth, realizations of rainfall spatial distribution and AMC conditions were entered as inputs to the model. Then, floods of different return periods were simulated by transforming rainfall to runoff. The approach was applied to Tangrah watershed in northeastern Iran. It was deduced that the spatial rainfall distribution and the AMCs exerted a varying influence on the peak discharge of different return periods. Comparing the results of the simulation approach with those of the statistical frequency analysis revealed that, for a given return period, flood quantiles based on the observed series were greater than the corresponding simulated discharges. It is also worthy to note that existence of outliers and the selection of the statistical distribution function has a major effect in increasing the differences between the results of the two approaches.     

Regional modelling of rainfall-induced runoff using hydrological model by incorporating plant cover effects: case study in Kelantan,Malaysia

The objective of this paper is to develop a spatial temporal runoff modelling of local rainfall patterns effect on the plant cover hilly lands in Kelantan River Basin. Rainfall interception loss based on leaf area index, loss/infiltration on the ground surface, and runoff calculation were considered as the main plant cover effects on the runoff volume. In this regard, a hydrological and geotechnical grid-based regional model (integrated model) was performed using Microsoft Excel^® and GIS framework system for deterministic modelling of rainfall-induced runoff by incorporating plant cover effects. The infiltration process of the current model was integrated with the precipitation distribution method and rainfall interception approach while the runoff analysis of integrated model was employed based on loss/infiltration water on the ground surface with consideration of water interception loss by canopy and the remaining surface water. In the following, the spatial temporal analysis of rainfall-induced runoff was performed using 10 days of hourly rainfall events at the end of December 2014 in Kelantan River Basin. The corresponding changes in pressure head and consequent rate of infiltration were calculated during rainfall events. Subsequently, flood volume is computed using local rainfall patterns, along with water interception loss and the remaining surface water in the study area. The results showed the land cover changes caused significant differences in hydrological response to surface water. The increase in runoff volume of the Kelantan River Basin is as a function of deforestation and urbanization, especially converting the forest area to agricultural land (i.e. rubber and mixed agriculture).     

Distribution of stable isotopes in arid storms

 Temporal distributions of the isotopic composition in arid rain storms and in the associated runoff were investigated in a small arid rocky basin in Israel. Customized rain and runoff samplers provided sequential water samples hermetically sealed in high-density PVC bags. In several storms where the runoff was isotopically depleted, compared with the rainfall, the difference could not be explained by fractionation effects occurring during overland flow. A water-balance study relating the runoff discharge to rainfall over a rocky watershed showed that the entire discharge is produced by a very small segment (1–2 mm) of the rain storm. The major objective, therefore, was to provide quantitative relations between segments of rainfall (rain showers and rain spells) and runoff. The time distribution of the composition of stable isotopes (oxygen and hydrogen) was used to quantify the correlation between the rain spell's amount and the consequent runoff. The aim of this work was to (a) utilize the dynamic variations in the isotopic composition in rainfall and runoff and model the magnitude of surface-storage capacity associated with runoff processes of overland flow, and (b) characterize the isotopic composition of the percolating water with respect to the isotopic distribution in rainfall and runoff events. The conceptual model postulates an isotopic mixing of overland flow with water within the depression storage. A transport model was then formulated in order to estimate the physical watershed parameters that control the development of overland flow from a certain rainfall period. Part I (this paper) presents the results and the assessment of the relative depression storage obtained from oxygen-18 and deuterium analyses that lead to the physical and mathematical formulation of a double-component model of kinematic-wave flow and transport, which is presented in Part II (accompanying paper). Received, February 1997 · Revised, September 1997 · Accepted, September 1997     

雨量站网布设对水文模型不确定性影响的比较

雨量站网布设会影响径流模拟精度,研究不同雨量站密度和空间分布的径流响应规律对提高径流模拟精度和减小不确定性具有重要意义。应用新安江模型和HBV（Hydrologiska Fyrans Vattenbalans）模型,以湘江流域为研究对象,采用贝叶斯方法比较分析在不同雨量站密度及空间分布下径流模拟的不确定性。结果表明:增加雨量站密度可以降低面雨量的估计误差,使模型在不同的雨量站空间分布下具有较高的模拟精度;通过优化雨量站空间分布,可以减小雨量站网布设导致的模型不确定性,从而提高径流模拟精度;在相同的降雨输入和参数采样方法下,新安江模型和HBV模型对降雨输入导致的不确定性响应规律具有相似性,但是本研究结果显示在湘江流域新安江模型的模拟精度更高,而HBV模型的不确定性更大。     

年径流频率分析的一次二阶矩法及其应用

针对流量资料极短时传统年径流频率分析方法——适线法不再适用的问题,分析了基于水文过程,由影响径流形成的因子推求年径流频率的一次二阶矩法的可行性,并讨论其在无流量资料流域应用中所存在的问题与解决方法。以江西省20个流域为研究对象,采用无参数Schreiber方程与单参数Fu-Zhang方程的水量平衡式作为年降雨—径流模型,结果表明:①一次二阶矩法的分析结果与实测年径流的经验频率较为吻合;②无流量资料流域中,忽略土壤含水量年间变化的作用,Fu-Zhang模型的分析结果比Schreiber模型好;③无流量资料流域中,Fu-Zhang模型中的参数ω可采用反距离权重法估计。     

七大流域水文特性分析

我国东西和南北方向地理跨度大,水文特性差异明显。从气候特征、降雨和径流、暴雨和洪水等方面,分析七大流域的水文特性,总结降雨和径流在上下游、干支流等空间上以及年内和年际等时间上的分布规律,并分析暴雨和洪水在成因、发生时间、空间分布、过程等方面的规律,为径流和洪水成果计算提供了基础,也为水文成果的合理性检验提供了参考。     

基于统计理论的产流模型

提出了一个基于统计理论的产流模型,该模型考虑了降雨、土壤下渗能力及土壤蓄水容量的空间变异性。假定每个时段的降雨量在空间上可以用概率密度函数或分布函数描述,根据实测降雨资料通过统计拟合优度途径估计各时段降雨的空间概率分布;采用抛物线型函数分别描述土壤下渗能力和土壤蓄水容量的空间分布。按照超渗产流机制计算地表产流量,通过降雨量和土壤下渗能力的联合分布推导得到地表径流量的统计分布,进而得到平均产流量的解析表达式。下渗水量补充土壤含水量,假定满足田间持水量后形成地下径流,其产流量根据下渗量和土壤蓄水容量的空间分配曲线进行计算。以半湿润的黄河支流伊河东湾流域为例,对模型进行了验证和应用,并与新安江模型的结果进行了对比。结果表明,模型对所研究的半湿润区的洪水模拟预报有较好的模拟效果。     

北江流域径流年内分配特征的变异性分析

以北江流域石角站53年的实测月径流资料为基础,研究了流域内径流年内分配特征及其变异性。计算了径流年内分配不均匀性、集中程度、变化幅度等指标。发现各年代和多年平均相比,20世纪50、60年代的径流年内分配较不均匀,70年代以后,径流年内分配逐渐趋于均匀,集中期和极小比的变化表现为具有波动性。从各指标的变化趋势看,不均匀系数、调节系数和极大比在1967、1975、1999年发生了变化,集中度在1999年发生了变化,集中期在1984、1999年发生了变化,极小比在1975、1983、1991、1999年发生了变化。径流年内分配特征的趋势变化和降雨不一致,主要表现在径流的年内分配不均匀性趋势较降雨降低,径流对降水的滞后时间延长,径流极大比变化趋势较降雨下降,极小比变化较降雨平稳。说明北江流域径流年内分配特征发生了变异。对流域内水利工程设施的修建、植被条件、城市化发展情况进行了分析,认为北江流域径流年内分配特征发生变异,主要是受到了上述人类活动的综合影响。     

Determination of potential runoff coefficient for Al-Baha Region,Saudi Arabia using GIS

The curve number (CN) is a hydrologic parameter used to describe the stormwater runoff potential for drainage areas, and it is a function of land use, soil type, and soil moisture. This study was conducted to estimate the potential runoff coefficient (PRC) using geographic information system (GIS) based on the area’s hydrologic soil group, land use, and slope and to determine the runoff volume. The soil map for the study area was developed using GPS data carried on to identify the soil texture to be used in building a soil hydrological groups map. Unsupervised and supervised classifications were done to Landsat 5/7 TM/ETM image to generate land-use and land-cover map. This map was reclassified into four main classes (forest, grass and shrub, cropland, and bare soil). Slope map for Al-Baha was generated from a 30-m digital elevation model. The GIS technique was used to combine the previous three maps into one map to generate PRC map. Annual runoff depth is derived based on the annual rainfall surplus and runoff coefficient per pixel using raster calculator tool in ArcGIS. An indication that in the absence of reliable ground measurements of rainfall product, it can satisfactorily be applied to estimate the spatial rainfall distribution based on values of R and R ² (0.9998) obtained. Annual runoff generation from the study area ranged from 0 to 82 % of the total rainfall. Rainfall distribution in the study area shows the wise use of identifying suitable sites for rainwater harvesting, where most of the constructed dams are located in the higher rainfall areas.     

基于改进型前馈神经网络的流域产流预报模型的研究

在分析流域产流机制、影响因素和现行产流计算方法的基础上,首次取前期影响雨量、主产流历时、全过程面平均雨量和４个代表雨强计７个因子作为神经网络输入,直接以流域产流深作为神经网络输出,并针对传统ＢＰ算法的固有缺陷,采用混合ＧＮ－ＢＦＧＳ算法训练网络。实例验证了所建模型及算法的有效性和可行性。还对神经网络隐层单位数等进行了初步研究。