共查询到18条相似文献,搜索用时 187 毫秒
1.
2.
蓄水容量曲线是反映流域缺水量空间分布不均匀性的特征曲线,对流域产流计算有直接影响。通过对多个典型流域蓄水容量空间分布的分析,发现Erlang分布能更好地拟合流域的蓄水容量曲线,进一步基于Erlang分布进行流域产流的推导,提出了基于Erlang分布蓄水容量曲线的流域产流模型。应用结果表明,基于Erlang分布的流域产流模型,增加了模型的适应性,模拟结果更接近流域实际的产流过程,比新安江模型能取得更高的模拟精度。此外,该产流模型的参数可由流域地形和土壤类型数据估算,为无资料地区的产流计算提供了一种可行的途径。 相似文献
3.
4.
黄河数字流域模型是“数字黄河”的重要组成部分,在数字流域模型框架下,以坡面为基本单元,建立了包括植被截留、融雪、地表蓄滞、表层土蓄滞、中层土蓄滞和深层土蓄滞共6层的产流模型.模型在垂向上考虑3层出流:地表超渗产流、表层土侧向渗流和中层土侧向渗流,既反映当前的降水过程,又体现前期降水过程和土壤前期含水量的影响,比较适合黄河流域的产流特点.在坡面产流的基础上,还给出了坡面单元侵蚀产沙公式,用于建立流域产沙数学模型.应用建立的模型,给出了3个计算实例:黄河全流域水量计算、小花区间汛期洪水模拟和多沙粗沙区产沙计算.实践表明:建立的模型基本具备了在黄河全流域进行降雨-径流模拟、侵蚀产沙计算的功能,辅以降雨预报模块则可进行洪水预报. 相似文献
5.
6.
首先构建一个以自然子流域为计算单元的分布式水文模拟系统,每一个计算单元内,利用土壤水蓄水容量曲线表示张力水的空间分布,在单元之间,认为坡度大的单元土壤层厚度和蓄水容量小,同样的降雨先产流。通过建立计算单元蓄水容量与地形坡度间的关系,考虑了地形坡度对产流的影响。在淮河流域上游大坡岭流域的应用结果表明,所用方法得到了理想的模拟结果。 相似文献
7.
基于饱和产流理论,针对辽宁中部平原“三水”转化规律,在实验研究资料分析基础上,建立了“三水”转化水文模型,模型将包气带土壤计算层分为上,下两层进行双层和损计算,对土壤张力水,应用指数型张力蓄水容量曲线计算总产水量,对土壤重力水,应用抛物线型重力水容量分布曲线进行地下水库调节,计算出地表径流量和地下径流量。 相似文献
8.
9.
10.
峰丛洼地坡面流径流过程——以丫吉试验场为例 总被引:1,自引:0,他引:1
选取裸露型和土壤植被覆盖型两种峰丛洼地地貌结构.通过降雨量、pH、电导率(Ec)、CO2分压和流量的过程线来分析降雨中详细的产流过程.裸露性坡地因包气带结构简单仅存在局部的超渗产流和表层岩溶带的回归流.水化学性质较稳定;有土壤植被覆盖的坡地的产流过程可以分为3个阶段:补偿阶段(可出现超渗产流)、饱和径流阶段、稳定阶段,补偿阶段仅在降雨强度大于入渗强度时可产生坡面流,饱和径流阶段坡面流流量与降雨强度成正比.稳定阶段坡面流流量趋于稳定,不随雨强的变化而变化,坡面流的水化学性质变化剧烈,pH、电导率(Ec)、CO2分压基本上同步变化,水漫(T)在降雨前期变化规律不明显.后期与pH、Ec等呈相反变化. 相似文献
11.
应用SWAT99.2模型(Soil and Water Assessment Tool),系统地研究了红壤丘岗集水区4种林草系统(自然草被、阔叶林、混交林和针叶林)的地表径流、根层渗漏、蒸发蒸腾、土壤蓄水量的时空特点,并用实测的地表径流对模型进行校正和验证,月地表径流的Nash-Sutcliffe模拟效率系数达到0.74,模拟值和观测值的决定系数达0.90。结果表明,降水的年内分配不均造成了径流、渗漏、土壤蓄水量月份之间的差异,年际间气象条件(特别是降水)的差异性导致了水量平衡支出项的年际差异,其中径流量和渗漏量受降水的影响最大,蒸发蒸腾量次之,土壤蓄水量的年变化量受降水的影响最小;林地能有效地减少区域的地表径流量,其中以阔叶林和混交林的效果最好;林地入渗性能大于草地;蒸发蒸腾量是林地水量平衡支出中最大的一项,且3种林地的蒸发蒸腾量均大于草地。水量平衡的预测结果显示,土地利用方式是区域短期水量平衡的主要影响因子。 相似文献
12.
针对降雨径流从坡面流下的过程中会发生下渗,导致土壤水非饱和带含水率增大这一动力学过程,从物理机制上对土壤水和地表水进行耦合,将二维平面地表水模型叠置在土壤水模型的顶部,对土壤水、地表水模型进行相同的空间和时间离散,在模型的计算过程中通过达西流关系对两者之间的水量交换进行计算(双层结点法耦合)或整合离散方程的整体法进行耦合。通过对两种耦合方法的比较以及与前人的实验结果对比,该模型与耦合方法能够准确地模拟和预测地表径流与土壤水分运动过程。研究结果可为分析地表水流与饱和-非饱和带水分与溶质耦合机理提供理论支持。 相似文献
13.
为实现中小流域降雨径流过程精细化模拟, 合理估算水文模型参数的空间分布具有重要意义。基于新版全球数字土壤制图系统(SoilGrids)构建栅格新安江模型(GXM)参数化方案, 对陕西省陈河流域2003—2012年16场洪水进行模拟, 与新安江模型计算结果进行对比, 开展基于洪水过程划分的自由水蓄水容量敏感性及空间分布特征量化分析。结果表明: GXM模拟的峰现时间误差水平降低约0.31 h, 洪峰和洪量模拟精度较高, 模型能够对土壤水饱和度等水文要素的动态空间分布进行较合理的模拟; 自由水蓄水容量参数对洪峰和涨洪过程的确定性系数以及涨洪段的洪量相对误差影响较大, 对退水过程影响小; 自由水蓄水容量在陈河流域河谷和山脊附近较大, 坡段中部较小。 相似文献
14.
15.
Shattri Mansor Nader Saadatkhah Zailani Khuzaimah Arnis Asmat Nor Aizam Adnan Siti Noradzah Adam 《Natural Hazards》2018,93(2):739-764
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). 相似文献
16.
在防止土壤侵蚀和雨后抑制蒸发的条件下,利用室内模拟降雨试验,研究了上方来水对坡面降雨入渗、湿润锋运移以及土壤水分再分布的影响。结果表明:对于初始含水量很低的土壤,与上方无来水相比,上方来水时降雨入渗过程中入渗率有一个上升的阶段,但平均入渗率反而降低;在降雨入渗初期,由于上方来水的沿程入渗,上方来水对坡面湿润锋运移的影响较大,但随后几乎没有影响,湿润锋的运移主要与基质势梯度有关;土壤水分沿坡面呈"波浪形"分布是坡面径流的波动性、上方来水(径流)的沿程入渗以及侧向沿坡向下流等综合作用的结果。 相似文献
17.
为了获取非饱和带水流过程的信息,借助流动电位正演模型,通过数值实验探讨非降雨和降雨两种条件下非饱和带流动电位和水流过程的关系,然后用南京中山植物园试验场地野外观测的流动电位和张力数据加以对比和验证。野外试验表明:流动电位可以有效地反映非饱和带水流过程。在夏季无降雨入渗的条件下,日周期变化的地表地下温度差导致水分的运动,流动电位准确地指示了非饱和带含水量和毛细压力的变化情况,从而指示出了水分运移的方向;在夏季有降雨入渗的条件下,降雨锋面推进之处,含水量和流动电位同时有明显的响应,进而根据不同位置的流动电位对降雨入渗响应的时刻差,直接求出入渗锋面的推进速度。 相似文献
18.
E. Zimmermann 《Hydrogeology Journal》2006,14(5):648-656
The Thornthwaite and Mather water budget is a simple and frequently applicable tool to estimate surpluses of water, which are not stored in the soil profile. Combining it with the empiric CN-method of the US Soil Conservation Service (US-SCS), which is applied to daily rainfall records, it is possible to estimate the runoff, and this way, from the difference between surpluses and runoff, to estimate the net infiltration that would recharge a phreatic aquifer. In order to apply both methods during a sequence of years, it is necessary to predict the number of rain events per month, and the rainfall depth for each event. In this work, the author proposes a methodology based on the theorem of Bayes to estimate the number of occurrences of rainy events in a considered month conditioning the forecast to the monthly rainfall. In addition, an exponential distribution to generate rainfall depth knowing the monthly rainfall was done. Both algorithms were applied in four stations of the southern region of Santa Fe province (Argentina). More than 7,600 forecasts of rain occurrences and rainfall depths were compared with the observed records. Moreover, the runoff values estimated by means of the US-SCS method, using the observed rainfall and using rainfalls predicted with the algorithms were also compared. In both cases, the obtained results were also very satisfactory. The proposed methodologies allow the correct application of the balance of Thornthwaite and Mather together with the US-SCS method and a good forecast of monthly runoff and net infiltration. 相似文献