Which condition can lead to increased risk of landslides?

• A. Stable groundwater levels
• B. Loss of vertical vegetative structure
• C. Presence of solid bedrock
• D. Flat terrain

Answer: (B)

The condition that can lead to an increased risk of landslides is the loss of vertical vegetative structure. Vegetation plays a critical role in maintaining soil stability, as plant roots help bind the soil together, reducing erosion and providing structural support. When there is a loss of this vegetative structure, such as through deforestation, land clearing, or fire, the soil becomes more susceptible to erosion and can lose its cohesion. Without the anchoring effect of the roots, the soil may become unstable, leading to potential landslides, especially on inclined surfaces where gravitational forces are at play.

In contrast, stable groundwater levels help maintain the soil's moisture balance and can support plant life, further reinforcing the soil structure. The presence of solid bedrock contributes to stability as it provides a strong foundation that resists movement. Flat terrain usually has a lower risk of landslides compared to steep slopes, as the gravitational forces on horizontal surfaces are not strong enough to trigger a landslide event. Therefore, the loss of vegetative structure is particularly a significant factor in the increased risk of landslides.