Q. Differentiate the causes of landslides in the Himalayan region and Western Ghats.
Question from UPSC Mains 2021 GS1 Paper
Model Answer:
According to the Geological Survey of India (GSI), ~12.6% of India is landslide-prone. The Himalayan and Western Ghats hotspots exhibit markedly distinct causal mechanisms.
1. Natural Factors
- Geology & Tectonics: Himalayas are seismically active, young fold mountains with friable sedimentary rocks. The Ghats are stable, ancient shields with deep lateritic weathering.
- Topography: Himalayas possess precipitous, structurally complex slopes and loose glacial moraines. The Ghats feature steep western escarpments highly susceptible to soil piping.
- Hydrometeorological Triggers: Himalayan slides are triggered by cloudbursts, glacial lake outbursts, and rapid snowmelt (Chamoli, 2021). The Ghats are destabilized by intense, concentrated orographic monsoonal downpours (Wayanad, 2024).
2. Anthropogenic Factors
- Infrastructure Development: The Himalayas suffer from deep hydropower tunneling, blasting, and unscientific slope-cutting for roads (Joshimath subsidence). The Ghats are primarily destabilized by unregulated stone quarrying and mining (Malin, 2014).
- Land Use Alteration: Himalayan slopes are mechanically burdened by unregulated urbanization for tourism. The Ghats face mass ecological degradation by replacing deep-rooted endemic forests with shallow-rooted commercial plantations (rubber, tea).
Sustainable resilience demands region-specific approaches: strictly enforcing the Madhav Gadgil Committee eco-sensitivity guidelines for the Ghats and adhering to NDMA’s Landslide Susceptibility Zonation protocols in the Himalayas.
