降雨动态系统响应曲线修正方法在黄土区域水沙模拟中的应用

采用水沙模型对流域水沙过程进行计算是目前分析和研究黄土地区水土流失、水沙锐减等问题的有效途径由于降雨的时段均化和缺测、漏测、误测等问题,导致水沙模型的重要输入项和动力因子——降雨资料存在误差,进而影响水流和泥沙过程模拟精度因此,本研究将降雨动态系统响应曲线的误差修正方法与概念性水沙模拟模型相结合以提高水沙过程模拟精度此方法将水沙模型的水流模拟部分看作响应系统,通过修正水沙模型的重要输入项——面平均雨量,利用修正之后的面平均雨量系列,通过模型重新计算以提高模型对产汇流和产汇沙过程的模拟精度通过理想案例验证该方法可行性后,选择黄土地区曹坪流域进行检验,结果表明修正后的水流和泥沙过程模拟精度均有显著提高,平均提高幅度分别为17.56%和15.86%.

Application of rainfall dynamic system response curve method for streamflow and sediment simulation in loess region

It is an effective way to use the conceptual model of water and sediment to calculate the water-sediment process in loess region to analyze the current soil erosion and water-sediment reduction problems. There are errors in the rainfall data due to the temporal homogenization, missing measurements and mismeasurements, which influence the accuracy of the important input variable and dynamic factor of the model-rainfall, and then affect the accuracy of flow and sediment process simulation. Therefore, this study combines the rainfall dynamic system response curve method with the conceptual model of water and sediment to improve the accuracy of water and sediment process simulation. This method takes the water simulation part of the model as a response system to update the important input variable-mean area rainfall. Then the runoff, sediment yield and concentration is recalculated using the updated rainfall series to improve the accuracy of flow and sediment process simulation. After validating the feasibility of this method by the ideal case, an actual case is occurred in Caoping Basin in loess region. The results show that the method can both significantly improve the accuracy of the water and sediment simulation, and the average increases are 17.56% and 15.86% respectively.