Analysis of runoff–storage relationships to evaluate the runoff-buffering potential of a sloping permeable domain
Analysis of runoff–storage relationships to evaluate the runoff-buffering potential of a sloping permeable domain
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DOI：
10.1016/j.jhydrol.2008.07.023
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发表时间：
2008-10
影响因子：
6.4
通讯作者：
M. Tani
中科院分区：
文献类型：
--
作者：
M. Tani
分析了稳定状态下径流系统的径流-库容关系，作为降雨-径流响应缓冲潜力的指标。在这一关系中，响应给定径流增加的大量储存增加表明在水平衡方程中具有较高的缓冲潜力。将该方法应用于倾斜渗透域。理查兹方程的二维形式被用来计算径流和储水量。大孔隙的存在表现为饱和附近导水系数的增大效应。径流量-库容关系受水量分布的控制。压头值的分布大致可分为3个区：垂直非饱和流I区、非饱和下坡流U区和饱和下坡流S区。通过径流-蓄能关系对压头分布分类的依赖关系，系统地评价了径流缓冲潜力。对于渗透性高的土壤，潜力通常很高，但在低径流率范围内，S区没有产生，潜力相当小。大孔效应通过增大I区使高缓冲电位范围向高径流速率范围转移。因此，中等大小的大孔效应使储水量在径流增加的情况下最大程度地增加。
The runoff–storage relationship for a runoff system in a steady-state is analyzed as an indicator of the buffering potential of rainfall-runoff responses. In this relationship, a large storage increase in response to a given runoff increase indicates high buffering potential in the water balance equation. The evaluation method is applied to a sloping permeable domain. A two-dimensional form of the Richards equation is used to calculate runoff and storage. Macropore existence is represented by an enlargement effect of hydraulic conductivity near saturation. The runoff–storage relationship is controlled by the distribution of hydraulic quantities. The distribution of a pressure-head value is approximately classified into the following three zones: the I zone with vertical unsaturated flow, the U zone with unsaturated downslope flow, and the S zone with saturated downslope flow. The runoff-buffering potential is systematically evaluated by dependencies of the runoff–storage relationship on the classification of the pressure-head distribution. The potential is generally high for soil with a high permeability, but rather small in the range of low runoff rates where the S zone is not created. The macropore effect causes the range of high buffering potential to shift to high runoff rates through enlargement of the I zone. As a result, a moderate magnitude of the macropore effect gives the maximum increase in storage in response to a given increase in runoff.