Effects of rainfall intensity fluctuations on infiltration and runoff: rainfall simulation on dryland soils, Fowlers Gap, Australia
Effects of rainfall intensity fluctuations on infiltration and runoff: rainfall simulation on dryland soils, Fowlers Gap, Australia
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DOI：
10.1002/hyp.8317
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发表时间：
2012-07-15
影响因子：
3.2
通讯作者：
Dunkerley, David
中科院分区：
文献类型：
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作者：
Dunkerley, David
使用小地块和滴头降雨模拟器来探索模拟降雨事件中强度波动（事件剖面）对裸露结皮旱地土壤渗透和径流的重要性。降雨的平均降雨率为 10 毫米/小时。 14 个模拟降雨事件每个都涉及超过 5000 次强度变化，包括事件早期或事件后期强度峰值为 25 毫米/小时的多峰事件以及包括暂时停雨的事件。这些都是自然降雨中常见的事件概况，但在降雨模拟中很少涉及。出于比较目的，还采用了降雨模拟实验中常用的恒定强度的矩形事件剖面。结果表明，事件剖面对这些土壤的入渗和径流以及降雨事件剖面具有重要影响。强度不变的均匀事件产生最低的总径流、最低的峰值径流率和最低的径流比（0.13）。这些参数对于早期峰值剖面（径流比 0.24）有所增加，对于晚期峰值剖面（径流比 0.50）达到最大值。均匀事件剖面和不同强度事件剖面之间的径流比和峰值径流率差异均在 p 时具有统计显着性。
Small plots and a dripper rainfall simulator were used to explore the significance of the intensity fluctuations (event profile) within simulated rainfall events on infiltration and runoff from bare, crusted dryland soils. Rainfall was applied at mean rain rates of 10?mm/h. Fourteen simulated rainfall events each involved more than 5000 changes of intensity and included multipeak events with a 25-mm/h peak of intensity early in the event or late in the event and an event that included a temporary cessation of rain. These are all event profiles commonly seen in natural rain but rarely addressed in rainfall simulation. A rectangular event profile of constant intensity, as commonly used in rainfall simulation experiments, was also adopted for comparative purposes. Results demonstrate that event profile exerts an important effect on infiltration and runoff for these soils and rainfall event profiles. Uniform events of unvarying intensity yielded the lowest total runoff, the lowest peak runoff rate and the lowest runoff ratio (0.13). These parameters increased for early peak profiles (runoff ratio 0.24) and reached maxima for late peak profiles (runoff ratio 0.50). Differences in runoff ratio and peak runoff rate between the uniform event profile and those of varying intensity were all statistically significant at p