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1.
作为滁州水文实验系统一部分的1号天然实验流域,面积7897m2,以安山岩为基底,上覆平均厚度2.46m的第四系沉积物。实测了包括地面径流和地面下径流的各种降雨径流响应,后者包括来自非饱和带的壤中流和饱和带的地下水径流。表明这些径流成分有着复杂的组合类型,主要是以地面径流为主的SR型和以地面下径流为主的SSR型,以及中间的和演化的类型。SR型实例中的地面径流量可占总径流的65%,而SSR实例中的地面下径流量可有90%。主要降水的7月,地面下贡献占54.5%,其中地下水径流即占33%。大部分地面径流与降水的18O组成有不小的差异,比较了同时进行测验的3个实验流域,在1400min的降水径流过程中,降水的平均δ18O为-1.210%,而同期地面径流的平均δ18O,2号水文山流域(512m2)为-1.132%,1号南大洼天然流域为-1.065%,3号只有薄层风化碎屑的牵牛花流域(4573m2)为-0.801%。这质疑了现行同位素流量过程线划分方法8个假定中的两个:地面径流的同位素组成不同于降水,天然流域尤其如此;各种水源在汇集过程中的同位素分馏影响并非都可忽略不计。实验流域因降水而产生径流,但所产生的径流却有着非本次降水的组分,这一降水径流悖论发生于各个实验流域。SR型和SSR型总的非本次降水组分分别达16%和64%。 相似文献
2.
降雨径流流域模型中的水源划分问题 总被引：2，自引：0，他引：2
在降雨径流流域模型中,水源划分是一个十分重要的环节.各种不同水源的径流,在汇流特性上差别很大:地面径流的坡地漫流时间不超过几小时;壤中流可达到三、五天,而地下径流则为几十天至百余天.如果水源划分处理不当,将对汇流计算带来很大困难.例如误将较多的地下径流计入地面径流中,则求得的单位线就峰低底宽,形成一种“非线性”.实际上,如果水源划分处‘理好了,这种“非线 相似文献
3.
自1987年起,在实验流域和代表流域对现行流量过程线划分两种径流成分的环境同位素法的基本假定进行了实验检验.结果表明,由于沉域水文系统同位素条件的复杂性,8项基本假定大多是不正确观念,应用该模型所得结果误差较大.研究认为对天然流域流量过程线使用环境同位素方法划分两种或两种以上径流组分时,必须具有4项必要条件,才能取得合理结果. 相似文献
4.
同位素示踪划分藤桥流域流量过程线的试验研究 总被引：9，自引：2，他引：9
在流域面积为３０３ｋｍ＾２的藤桥流域（山区）。对现行同位素流量过程线划分方法的合理性，用环境同位素氧－１８作了试验研究，现行方法在其两种径流式成分的混合模型中，对降雨和地下径流均用单一同位素含量表征是不正确的，将导致划分结果有误差，由图解划分方法所得的地下径流，在本工作条件下，表明它近似于块状岩来裂隙水为主的地下补给，不包括主要属第四纱的风化层和冲积堆积层的地下径流部位，由试验结果可见，利用环境同 相似文献
5.
采用人工模拟降雨的方法,在山西太谷均衡实验站野外径流试验场上.对平原区地面产流机制进行了试验与研究.本文就平原区地面径流的计算方法进行了探讨,利用径流系数法将人工模拟均匀降雨的试验结果应用于人工模拟非均匀降雨和天然降雨的地面径流计算,取得了较好效果. 相似文献
6.
平原区的水文计算在当前生态重建环境中具有重要意义.利用仿雨试验,研究地面坡度小于 3‰的平原区降雨产流的特征,稳定降雨条件下径流系数的变化规律,提出了"最大径流系数法"对平原降雨产流的计算原理,对非稳定及天然条件下的暴雨过程进行了径流计算.结果表明:(1)对仿雨实验变雨强径流计算,计算值与实测值比较相对误差平均为 6.43%;(2)对天然降雨过程的径流计算,计算实例结果误差为 5.9%和 10.9%. 相似文献
7.
主要目的是通过对同位素在流域水文模拟应用中的一些假定、限制条件以及方法进行澄清和系统化,从而促进同位素在流域水文模拟中一些新的研究方向和研究热点.主要从三个方面,即同位素流量过程线分割、流域平均滞时与不同水源混合、与水文模型耦合,讨论同位素示踪剂在流域水文模拟中的研究进展情况.同时指出了同位素在流域水文模拟中应用存在的一些主要问题,包括:①降雨同位素含量的时空变化;②不同径流成分的采样;③径流输出同位素含量的空间变化;④流域平均滞时分布函数的确定;⑤水文同位素耦合模型. 相似文献
8.
贡嘎山海螺沟冰川径流水文规律的同位素示踪研究 总被引：3，自引：1，他引：2
应用同位素地球化学的基本原理和示踪技术, 对贡嘎山海螺沟冰川河源区和干流的不同区段, 不同时域径流的组成特点及其水文动态变化规律进行分析研究.结果表明: 贡嘎山海螺沟冰川河源区水的组成, 不同季节、不同时段(早、晚)有明显的变化. 夏季晚上的水大约有82.4%是来自冰川区的水, 17.6%为非冰川区的径流; 早晨中的水来自冰川区的占74.6%, 非冰川区径流占25.4%. 冰川消融水的最大可占总水量的6.9%～7.8%左右. 在冬季时段, 冰舌末端排泄水(BCH-1)和冰川水文站(HLG-6)径流的同位素组成均低于底部冰川冰(BCB-2: -16.639‰), 显示出严重同位素不平衡的特点, 反映了冬季底部冰川消融水在源区水(BCH-1)中的贡献已达很低的程度, 而代之以冰川上部占主导优势的雨雪水. 这意味着在冬季当地冰川的退缩速度与夏季相比有明显减慢的趋势. 示踪表明, 在冰川水文站附近区域内存在水的渗漏, 夏季可能延伸到倒中桥(HLG-13采样点上方)一带, 下渗水通过地下通道, 到杉树坪(HLG-2采样点)邻近的区域回补到河道内. 相似文献
9.
桂林岩溶区的水量转化问题 总被引：2，自引：0，他引：2
<正>岩溶区的大气降水、地表水、岩土水、地下水同处于一个水循环系统,相互关系密切,水量转化较非岩溶区更为频繁。本文根据广西桂林地区气候背景与岩溶地质条件分析几种主要岩溶含水系统,包括系统结构,系统输入与输出关系(降雨径流关系)以及降雨入渗与水源分配。并针对水量转化中流域不闭合问题,采用水均衡法估算岩溶区地下汇水面积。 相似文献
10.
为揭示高寒山区冻土对降雨-径流过程的影响,对黑河上游红泥沟小流域典型降雨事件全过程出口断面的径流量进行了观测,采集降雨和河水样品,测定其中溶解硅的质量浓度,进而分析径流量和溶解硅质量浓度的动态变化规律,并以溶解硅为示踪剂将小流域出口径流分割为地面径流(腐殖层中流和坡面流)和地下径流(矿质层中流)。结果表明,洪峰上升期,地面径流对河道径流的贡献率为47%,地下径流贡献率为53%;洪峰降落期,地面径流贡献率为29%,地下径流贡献率为71%。整个观测过程中地面径流对河道径流的贡献率为30.7%,地下径流的贡献率为69.3%,说明洪峰期间河道径流以地下径流为主。分析认为冻土分布地区夏季降雨-径流过程中,由于土壤逐渐解冻,降雨入渗驱替冻土层上水排入河网,流域产流仍以地下径流为主。 相似文献
11.
为揭示中、低纬度高寒山区降雨-径流的形成过程,指导水资源的合理开发利用,选择黑河上游红泥沟小流域为研究区,基于河道径流量及雨水和河水稳定同位素的观测数据,构建二元混合模型,计算了2013年7月23日及8月21日两次典型降雨-径流事件中事件水（降雨）和事件前水（流域前期储水）对河道径流的贡献及其动态变化.结果显示:两次降雨事件中事件前水的贡献比例分别为68.69%和54.46%;事件前水的贡献比例在涨水阶段减小,在退水阶段增大.结合河水电导率的观测结果,进一步分析了降雨-径流的形成过程:河道径流的形成主要受饱和区蓄满产流、河岸带地下径流和山坡地下径流3种产流机制控制;事件水主要源于蓄满产流,事件前水主要源于河岸带和山坡地下径流;事件初期和末期以河岸带地下水补给为主,涨水阶段后期和退水阶段前期转为以蓄满产流和山坡地下水补给为主,洪峰期间蓄满产流的贡献达到最大.两次事件的对比表明,事件前的湿度条件和降雨强度对降雨-径流的形成过程有着重要影响:前期越湿润,流域储水能力越弱,导水能力越强,事件水的贡献越大,河道径流对降雨的响应越迅速;降雨强度越大,蓄满产流及其中的事件水比例越高,河道径流中事件水的比例也越高. 相似文献
12.
A multi-method approach to quantify groundwater/surface water-interactions in the semi-arid Hailiutu River basin,northwest China 总被引：1，自引：0，他引：1
Identification and quantification of groundwater and surface-water interactions provide important scientific insights for managing groundwater and surface-water conjunctively. This is especially relevant in semi-arid areas where groundwater is often the main source to feed river discharge and to maintain groundwater dependent ecosystems. Multiple field measurements were taken in the semi-arid Bulang sub-catchment, part of the Hailiutu River basin in northwest China, to identify and quantify groundwater and surface-water interactions. Measurements of groundwater levels and stream stages for a 1-year investigation period indicate continuous groundwater discharge to the river. Temperature measurements of stream water, streambed deposits at different depths, and groundwater confirm the upward flow of groundwater to the stream during all seasons. Results of a tracer-based hydrograph separation exercise reveal that, even during heavy rainfall events, groundwater contributes much more to the increased stream discharge than direct surface runoff. Spatially distributed groundwater seepage along the stream was estimated using mass balance equations with electrical conductivity measurements during a constant salt injection experiment. Calculated groundwater seepage rates showed surprisingly large spatial variations for a relatively homogeneous sandy aquifer. 相似文献
13.
Alexander Yakirevich Avraham Dody Eilon M. Adar Viacheslav Borisov Mebus Geyh 《Hydrogeology Journal》1998,6(1):50-65
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 相似文献
14.
无机水化学离子在实验流域降雨径流过程中的响应及其示踪意义 总被引：1，自引：0，他引：1
为研究无机水化学离子在降雨径流示踪中的可能性,在实验流域实测降雨、地面径流、壤中流、地下水径流过程和流域内17个测孔的地下水过程中,施测了Na+,K+,Ca2+,Mg2+,Cl-,SO42-,HCO3-+CO32-,NO3-,F-,NH4-,PO42-,SiO2和pH,EC,18O的同步过程,还施测了少数土壤水水样。结果是:①在Ca2+与Cl-/SO42-和EC与Na+/(Na++Ca2+)的关系中以及除NO3-,NH4-,PO42-外的所有离子,都可识别出上述各种径流组分;②径流离子过程均与降雨离子过程相仿,随径流组分从地面到地下而渐趋坦化;③除个例外,离子浓度过程均以降雨为最小并从地面径流到地下水径流渐次增大;④降雨和地下水离子过程表现为径流离子过程的两端元;⑤在降雨和各径流组分中,18O过程与大部分离子过程有一定的同步性。从以上结果认为,降雨并不是流域径流离子输出的主要来源,然而却是形成它的主要控制因素。此外,有关试验结果还对应用Cl-进行地下水补给的估算方法提出了问题。 相似文献
15.
The hydrograph separation of the Amazon river was performed using three different methodologies. Were applied isotopic, filter-separation, and mixing methods to estimate the contributions of the surface runoff (event water) and baseflow (pre-event water) components to the total river flow, during the 1973–1974 hydrological years. The importance of the baseflow contribution, mainly during the peak discharge, suggesting that the groundwater plays a much more active and important role in the storm dynamics, was verified. Similar results were obtained for all the methods used, and the applicability of each one was discussed in detail. For the Amazon river basin, the average contribution of the baseflow was 56% of the total river flow, at peak discharge. The average surface runoff contribution, which represents the water capable of mechanical erosion in drainage basins, expressed in terms of the surface runoff coefficient (Kr), was 31.9%, while the mean contribution of the baseflow, expressed by the baseflow coefficient (Kb), was 68.1%. 相似文献
16.
通过环境同位素、水文分割法和相关分析研究表明,祁连山区降水、冰川雪融水和基岩裂隙水通过出山口地表径流补给构成黑河流域走廊平原地下水主要补给源,具有年际和年内丰枯动态变化规律,与祁连山区降水量和气温的关联度分别为0.97和0.79,与平原张掖站降水量和气温的关联度分别为0.43和0.60。在自然径流条件下,祁连山区降水量变化是改变走廊平原地下水补给的主导因素,约占91%权重;气温变化是重要影响因素,约占9%权重。20世纪80年代以来祁连山区各补给源处于偏丰期。因此,近年来走廊平原地下水补给量相对50年代减少27.1%,人类活动是重要影响因素,急需加强科学调控。 相似文献
17.
The prospect of changing climate has led to uncertainty about the resilience of forested mountain watersheds in the tropics. In watersheds where frequent, high rainfall provides ample runoff, we often lack understanding of how the system will respond under conditions of decreased rainfall or drought. Factors that govern water supply, such as recharge rates and groundwater storage capacity, may be poorly quantified. This paper describes 8-year data sets of water stable isotope composition (δ2H and δ18O) of precipitation (4 sites) and a stream (1 site), and four contemporaneous stream sample sets of solute chemistry and isotopes, used to investigate watershed response to precipitation inputs in the 1780-ha Río Mameyes basin in the Luquillo Mountains of northeastern Puerto Rico. Extreme δ2H and δ18O values from low-pressure storm systems and the deuterium excess (d-excess) were useful tracers of watershed response in this tropical system. A hydrograph separation experiment performed in June 2011 yielded different but complementary information from stable isotope and solute chemistry data. The hydrograph separation results indicated that 36% of the storm rain that reached the soil surface left the watershed in a very short time as runoff. Weathering-derived solutes indicated near-stream groundwater was displaced into the stream at the beginning of the event, followed by significant dilution. The more biologically active solutes exhibited a net flushing behavior. The d-excess analysis suggested that streamflow typically has a recent rainfall component (∼25%) with transit time less than the sampling resolution of 7 days, and a more well-mixed groundwater component (∼75%). The contemporaneous stream sample sets showed an overall increase in dissolved solute concentrations with decreasing elevation that may be related to groundwater inputs, different geology, and slope position. A considerable amount of water from rain events runs off as quickflow and bypasses subsurface watershed flowpaths, and better understanding of shallow hillslope and deeper groundwater processes in the watershed will require sub-weekly data and detailed transit time modeling. A combined isotopic and solute chemistry approach can guide further studies to a more comprehensive model of the hydrology, and inform decisions for managing water supply with future changes in climate and land use. 相似文献
18.
Use of oxygen-18 isotope to quantify flows in the upriver and middle reaches of the Heihe River,Northwestern China 总被引：3，自引：0，他引：3
In recharge areas, the Heihe River flow was separated into components of ice-snowmelt and precipitation according to 14 gauging
stations and to monthly hydrograph using oxygen-18. As shown by the result of the two-component mixing model, on average,
19.8% of the runoff comes from ice-snowmelt. At three stations which are closer to glaciers and with headstream of ice-snow
melted water, the ice-snowmelt runoff is larger than 28% of stream water. In addition, because most of the ice-snowmelt infiltrates
the groundwater, which later discharges into the river at mountain outlets, the ice-snowmelt percentage in runoff is lower
than average at these stations with the elevation higher than 3,600 m. According to monthly hydrograph, the lowest percentage
of ice-snowmelt in runoff is in July (6.46%), whereas during November it is the largest (26.1%). In the middle basin, the
fraction of groundwater in runoff had a marked increase from 23.57% near Zhangye City to 60.28% near Gaotai City, and then
a dramatic drop to 13.61% near Zhengyixia Station because of agricultural flood irrigation in Zhangye Basin. 相似文献
19.
针对现行流量过程线分割方法中存在着缺乏物理基础和客观的、科学的操作方法，以及其他的一些问题，提出了流量过程线的分割应遵循的三条基本原则，在此基础上提出流量过程线分割的新方法。该法通过流域的降雨资料和出口断面的流量资料，经推导得到Horton下渗能力曲线的三参数，并推导出地下净雨量在非饱和带运行时间公式和地下水汇流公式，从而对流域出口断面流量过程线进行分割。 相似文献