Question

Consider the following factors. Which of them are common causes of landslides?

1. Heavy rainfall can saturate soil, significantly increasing its weight and reducing its stability.
2. Soil erosion strengthens slopes by removing loose material, making them more resilient.
3. Earth tremors and seismic activity can destabilize the ground, triggering mass movements.
4. Areas under heavy snow are prone to landslides due to the weight of the snow and ground saturation from melting.

• A. മൂന്ന് മാത്രം
• B. ഒന്നും മൂന്നും നാലും
• C. ഒന്നും മൂന്നും
• D. നാല്

Answer 1

Answer:

B. ഒന്നും മൂന്നും നാലും

Landslides are often triggered by a combination of natural factors. Heavy rainfall is a major cause, as water infiltrates the soil, reducing friction and increasing its weight, leading to instability. Soil erosion, conversely, weakens slopes by removing the protective topsoil and vegetation, making them more susceptible to collapse. Earth tremors cause ground shaking that can dislodge unstable masses. Furthermore, the presence of heavy snow, especially during rapid melting, can saturate the ground and exert additional pressure, contributing to slope failure. Human activities like mining, construction, and deforestation can also increase the susceptibility of slopes to landslides by altering natural drainage patterns and removing stabilizing vegetation.