Subsurface storm flow formation at different hillslopes and implications for the ‘old water paradox’
Subsurface storm flow formation at different hillslopes and implications for the ‘old water paradox’
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不同山坡的地下风暴流形成及其对“旧水悖论”的影响
DOI：
10.1002/hyp.6687
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发表时间：
2008
影响因子：
3.2
通讯作者：
F. Naef
中科院分区：
文献类型：
--
作者：
P. Kienzler;F. Naef
虽然过去几十年的许多研究已经证明了山坡地下风暴流（SSF）的重要性，但它的形成仍然没有得到很好的理解。因此，我们研究了4个不同山坡在控制洒水试验和自然降雨条件下渗透土壤带中SSF的形成。使用人工示踪的洒水和222Rn作为天然示踪剂来测定事件和事件前的水组分。在不同的山坡上，SSF的形成和事件前水的比例有很大的差异。SSF的强度和事件前水分的比例都取决于优先流道中的SSF是直接来自降水还是间接来自土壤的饱和部分。土壤水分从土壤基质中的饱和斑块中迅速调动，随后释放到更大的孔隙中，在那里与事件水混合。因此，大量的事件前水包含在快速流动成分中，如地下风暴流和陆地流。这一发现对常用的水图分离方法产生了影响，并可能部分解释“老水悖论”。版权所有©2007 John Wiley & Sons， Ltd
Although many studies over the past several decades have documented the importance of subsurface stormflow (SSF) in hillslopes, its formation is still not well understood. Therefore, we studied SSF formation in the vadose soil zone at four different hillslopes during controlled sprinkling experiments and natural rainfall events. Event and pre‐event water fractions were determined using artificially traced sprinkling water and 222Rn as natural tracer. SSF formation and the fraction of pre‐event water varied substantially at different hillslopes. Both intensity of SSF and fraction of pre‐event water depended on whether SSF in preferential flow paths was fed directly from precipitation or was fed indirectly from saturated parts of the soil. Soil water was rapidly mobilized from saturated patches in the soil matrix and was subsequently released into larger pores, where it mixed with event water. Substantial amounts of pre‐event water, therefore, were contained in fast flow components like subsurface storm flow and also in overland flow. This finding has consequences for commonly used hydrograph separation methods and might explain part of the ‘old water paradox’. Copyright © 2007 John Wiley & Sons, Ltd.