Rainwater infiltration in a vegetated slope subjected to high intensity rainfall

Abstract

Vegetation is widely accepted as an effective and environmentally friendly approach to mitigating slope failure. However, due to global warming, very high rainfall intensity might become more common. Rainwater infiltration in a sloping ground was studied, using a vegetated slope model subjected to very high rainfall intensity. The model slope was planted with the grass species Axonopus compressus to create two soil layers of uniform thickness, one with plant roots and one without. It was found that, for every simulated rainfall intensity used in this study, water infiltrated vertically in both soil layers. Furthermore, even under simulated rainfall of very high intensity, there existed a final infiltrated water content (${\theta }_f$) whose magnitude could be approximated from the k-function of the soil and the final infiltration capacity. Results from this study would enhance the knowledge of rainwater infiltration in a vegetated slope subjected to high rainfall intensity, and hence the stability assessment of vegetated slopes.