Analyzing the effects of eco-DRR practices on slope stability in a landslide-prone transport corridor in the Western Ghats, India

This study focuses on the effectiveness of ecosystem-based disaster risk reduction (eco-DRR) in stabilizing the Kallar-Ponmudi road corridor in the Western Ghats of Kerala, India, which is susceptible to rainfall-induced shallow landslides. To assess slope stability, the authors used a physics-based, GIS-integrated program that simulates the timing and distribution of shallow landslides triggered by rainfall. Using this model, the authors selected high susceptibility regions as the location of their study to evaluate the effectiveness of different eco-DRR measures in stabilizing the slopes. 

Five different slope conditions were tested under artificial rainfall. The results show that vegetative measures, particularly deep-rooted plants like vetiver grass, significantly enhanced slope stability compared to other reinforcements. Vegetative solutions using shallow- and deep-rooted species also strengthen soil through root reinforcement. Additionally, shallow roots reduce surface erosion whereas deep roots facilitate improved shear strength and subsurface stability, while also being readily available and low-cost.