How Do Ground Litter and Canopy Regulate Surface Runoff?—A Paired-Plot Investigation after 80 Years of Broadleaf Forest Regeneration

Abstract

Relatively minimal attention has been given to the hydrology of natural broadleaf forests compared to conifer plantations in Japan. We investigated the impacts of ground litter removal and forest clearing on surface runoff using the paired runoff plot approach. Plot A (7.4 m2) was maintained as a control while plot B (8.1 m2) was manipulated. Surface runoff was measured by a tipping-bucket recorder, and rainfall by a tipping-bucket rain gauge. From May 2016 to July 2019, 20, 54, and 42 runoff events were recorded in the no-treatment (NT), litter removed before clearcutting (LRBC), and after clearcutting (AC) phases, respectively. Surface runoff increased 4× when moving from the NT to LRBC phase, and 4.4× when moving from the LRBC to AC phase. Antecedent precipitation index (API11) had a significant influence on surface runoff in the LRBC phase but not in the NT and AC phases. Surface runoff in the AC phase was high regardless of API11. The rainfall required for initiating surface runoff is 38% and 56% less when moving from the NT to LRBC, and LRBC to AC phases, respectively. Ground litter and canopy function to reduce surface runoff in regenerated broadleaf forests.

Long-Term Monitoring and Research in Forest Hydrology: Towards Integrated Watershed Management

“…This Special Issue collected ten original contributions focused on forest hydrology based on long-term data and integrated watershed management. Two of them were developed in China [1,2] and Japan [3,4], while the rest were from the United States [5], Korea [6], Brazil [7], Vietnam [8], Indonesia [9], and Slovakia [10].…”

“…Topic 1 comprises eight publications, including various scales, such as global [2], large catchment [8], natural lake [4], experimental catchments [5,9], experimental plots [1,3], and simulations [6].…”

“…Nainar et al [3] investigated the impacts of ground litter removal and forest clearing on surface runoff using a paired runoff plot approach in the Ananomiya Experimental Watershed, Aichi, Japan. They found that the surface runoff increased four times when moving from the no-treatment to litter removed before the clearcutting phase, and 4.4 times when moving from the litter removed before clearcutting to after the clearcutting phase.…”

Comparison between biophysical analysis model and dimidiate pixel model for the estimation of forest canopy density

“…On the contrary, decreasing FCD increases the surface runoff. 18,19 Therefore, accurate estimation of FCD and its spatial distribution can help understand and monitor forest resource information and provide an important basis for forest management decision-making and forest ecosystem management.…”

“…Moreover, with increasing FCD, the interception effect of the forest canopy reduces the precipitation directly falling on the ground, thereby decreasing surface runoff. On the contrary, decreasing FCD increases the surface runoff 18 , 19 . Therefore, accurate estimation of FCD and its spatial distribution can help understand and monitor forest resource information and provide an important basis for forest management decision-making and forest ecosystem management.…”