Effects of rainfall intensity and slope on interception and precipitation partitioning by forest litter layer

• Published in: Catena (Giessen) Vol. 172; pp. 711 - 718
• Main Authors: Du, Jie, Niu, Jianzhi, Gao, Zhaoliang, Chen, Xiongwen, Zhang, Linus, Li, Xiang, van Doorn, Natalie S., Luo, Ziteng, Zhu, Zhijun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-01-2019
• Subjects: Earth and Related Environmental Sciences; Forest litter; Geovetenskap och miljövetenskap; Interception; Natural Sciences; Naturgeografi; Naturvetenskap; Oceanografi, hydrologi och vattenresurser; Oceanography, Hydrology, Water Resources; Physical Geography; Precipitation partitioning; Rainfall intensity; Slope gradients; Precipitation partitioning; Slope gradients; Interception; Rainfall intensity; Forest litter
• ISSN: 0341-8162; 1872-6887
• DOI: 10.1016/j.catena.2018.09.036

Rainfall interception and other hydrologic processes affected by the forest litter layer are usually related to litter characteristics and rainfall conditions, with limited studies that consider the influence of slope. To simulate the hydrological functions of the litter layer at different slope gradients, artificial rainfall experiments were conducted at four rainfall intensities (from 30 to 120 mm hr−1) in horizontal and inclined trays (with the slope of 0°, 10°, 20° and 30°) with litter of Pinus tabuliformis or Quercus variabilis. The results indicated that (1) the dynamic process of litter interception had 3 phases: a rapid intercepted phase within the first 5 min, a moderate intercepted phase and a post-rainfall drainage phase; (2) the maximum interception storage (Cmax) and the minimum interception storage (Cmin) of Q. variabilis were larger than those of P. tabuliformis; (3) Cmax and Cmin were correlated with slope for both types of litter, whereas only Cmax was correlated with rainfall intensity; and (4) lateral flow amount significantly increased with both slope gradient and rainfall intensity only for Quercus variabilis, whereas drainage volume showed significant correlation with rainfall intensity. Moreover, the ratio of lateral runoff and drainage was affected by slope gradient whereas percentage of litter interception had a good relationship with rainfall intensity, rather than slope, with litter interception and drainage contributing the smallest and the largest proportions, respectively. Overall, the results demonstrate the effect of rainfall and slope factors on hydrological processes in the forest litter layer.
•Different rain intensities and slopes were tested for litter hydrologic process.•Litter interception was a dynamic process including three phases.•Both Cmax and Cmin of Q. variabilis were larger than P. tabuliformis.•Slope affected both Cmax and Cmin while rain intensity only affected Cmax.•Rain partitioning of litter layer was affected by both rain intensity and slope.