Hydraulic Causes for Basin Hydrograph Skewness
Hydraulic Causes for Basin Hydrograph Skewness
复制标题
流域过程线偏度的水力原因
DOI：
10.1002/2017wr021543
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发表时间：
2017
影响因子：
5.4
通讯作者：
A. Mejia
中科院分区：
文献类型：
--
作者：
W. Collischonn;A. Fleischmann;R. Paiva;A. Mejia
研究表明，过程线偏度取决于坡面和河网输运过程的相对优势，前者使过程线正偏，而后者则倾向于使过程线负偏。然而，最近，河流水力学在形成过程线中的作用得到了强调。我们提出了一组使用河流网络水动力模型的数值模拟实验，其中我们研究了渠道水力学如何影响过程线的形状，特别是其偏斜度。我们进一步研究基流，降雨强度，横截面的几何形状，和流域尺度上的单位线响应的影响。我们表明，河流水力学具有决定性的作用，因为正偏过程线可能会发生，即使当水输入到河流网络是负偏，并在集水区的宽度功能也是负偏。我们展示了额外的结果相关的非线性度的影响，在celestration和流量之间的关系，基流和降雨强度的影响。这些进一步证实，水力因素可能是决定性的过程线形状。
It has been suggested that hydrograph skewness depends on the relative dominance between hillslope and channel network transport processes, where the former ones make the hydrograph positively skewed while the latter tends to make it negatively skewed. More recently, however, the role of river hydraulics in shaping the hydrograph has been highlighted. We present a set of numerical modeling experiments using a hydrodynamic model of river networks in which we investigate how channel hydraulics influence the shape of the hydrograph, particularly its skewness. We further investigate the influence of base flow, rainfall intensity, cross section geometry, and basin scale on unit hydrograph response. We show that river hydraulics has a decisive role because positively skewed hydrographs may occur even when water inputs to the river network are negatively skewed, and in catchments whose width function is also negatively skewed. We show additional results related to the effect of the degree of nonlinearity in the relationship between celerity and discharge, the effects of base flow and rainfall intensity. These further confirm that hydraulic factors may be decisive in determining hydrograph shape.