Variability of surface runoff generation and infiltration rate under a tree canopy: indoor rainfall experiment using Japanese cypress (Chamaecyparis obtusa)
Variability of surface runoff generation and infiltration rate under a tree canopy: indoor rainfall experiment using Japanese cypress (Chamaecyparis obtusa)
复制标题
DOI：
10.1002/hyp.7551
复制
发表时间：
2010-02
影响因子：
3.2
通讯作者：
K. Nanko;Y. Onda;Akane Ito;S. Ito;S. Mizugaki;H. Moriwaki
中科院分区：
文献类型：
--
作者：
K. Nanko;Y. Onda;Akane Ito;S. Ito;S. Mizugaki;H. Moriwaki
为了估计森林地区地表径流产生的变化和裸露地表的渗透率，在带有喷嘴（高度为16 m）的大型降雨模拟器中使用13个径流箱和一棵移植的日本柏树（高度为9.8 m）进行了室内试验。应用降雨和12种不同强度和动能（KE）的穿透雨（发现在测量点和冠层结构）的地表径流进行了测量。虽然没有观察到任何地表径流的应用降雨，地表径流观察到穿透在每个径流箱。与降雨相比，穿透雨由于冠层滴水的产生而具有较大的滴度，因此具有较高的动能，从而降低了入渗能力。穿透雨的最大稳定入渗速率（IRMAX）最低（44·2 mm h−1）。地表产流和入渗速率变化很大的树冠下，即使降雨量的应用是相同的，径流箱具有相同的初始土壤性质。IRMAX的变化范围为44·2 ~ 120·2 mm h−1，是由穿透雨强度和动能的变化引起的。与IRMAX相关性最好的指标是有效单位动能（KE 0 mm：J m−2 mm−1）。预测森林地区的地表径流，需要估计穿透雨的量和动能的空间变化。版权所有© 2010约翰威利父子有限公司.
To estimate the variability of surface runoff generation and the infiltration rate on a bare surface in a forested area, indoor experiments were conducted using 13 runoff boxes and a single transplanted Japanese cypress tree (9·8 m in height) in a large‐scale rainfall simulator with spray nozzles (at a height of 16 m). The surface runoff was measured for applied rainfall and for 12 kinds of throughfall with different intensities and kinetic energy (KE) (found among measuring points and canopy structures). While no surface runoff was observed for the applied rainfall, surface runoff was observed for throughfall in each runoff box. Compared with the applied rainfall, the throughfall had larger drops due to canopy drip generation and thus had higher kinetic energy, which decreased the infiltration capacity. The maximum stable infiltration rate (IRMAX) was lowest for throughfall (44·2 mm h−1). Surface runoff generation and infiltration rates varied greatly under the canopy, even though the rainfall applications were identical and the runoff boxes had identical initial soil properties. The variability of IRMAX, ranging from 44·2 to 120·2 mm h−1, was caused by the variability of the throughfall intensity and kinetic energy. The index showing the best correlation to IRMAX was the effective unit kinetic energy (KE0 mm: J m−2 mm−1). The prediction of surface runoff generation in a forested area requires estimations of the spatial variations of the amount and kinetic energy of throughfall. Copyright © 2010 John Wiley & Sons, Ltd.