(a) Landslide is a major problem in Himalayan region. Discuss its causes and mitigation measures. 20 (b) Appraise why drought is…

India’s complex physiographic and hydro-climatic architecture exposes distinct geomorphic zones to differentiated disasters, ranging from mass wasting in the young fold mountains of the north to pervasive water stress across peninsular drylands.

Landslides in the Himalayan Region: Causes and Mitigation

The Himalayan arc is inherently prone to mass movements due to ongoing Indo-Eurasian tectonic convergence, high seismicity, fragile lithology of thrust zones (such as the Main Central Thrust), and extreme slope gradients with high relief energy. Intense monsoon downpours and glacial melt rapidly elevate pore-water pressure along shear planes, triggering slope failures.

These natural vulnerabilities are magnified by anthropogenic pressures. Unscientific road-widening, unmitigated blasting, slope toe-cutting for infrastructure, unregulated tourism, and deforestation remove stabilizing vegetative cover and disrupt the natural angle of repose.

Mitigation necessitates an integrated framework aligned with National Disaster Management Authority (NDMA) guidelines, balancing structural and non-structural interventions:

• Structural Measures: Slope stabilization using rock bolting, hydro-seeding, retaining walls, and wire-mesh geo-textiles. Dewatering through surface and sub-surface drainage network correction is critical to prevent pore-pressure buildup.
• Non-Structural Measures: Bio-engineering via deep-root species (such as vetiver grass), Landslide Hazard Zonation (LHZ) to regulate slope-loading, radar- and rain-gauge-coupled Early Warning Systems (EWS), and strict enforcement of Himalayan hill-building bylaws.

Drought as a Climatic Extreme in India

Drought is India’s most frequent climatic extreme due to an acute dependence on the South-West Monsoon, which delivers over 75% of annual precipitation within four months. This system is subject to spatial-temporal unpredictability and atmospheric anomalies, particularly the El Niño-Southern Oscillation (ENSO) and negative Indian Ocean Dipole phases. Regions in Northwest India and the Peninsular rain-shadow (Rayalaseema, Marathwada) face chronic vulnerability, with the rainfall coefficient of variation exceeding 30 to 40%.

This meteorological exposure translates rapidly into hydrological and agricultural distress because nearly 50% of India’s net sown area remains rainfed and devoid of assured irrigation. Decades of water-intensive cropping (like paddy and sugarcane) have led to severe groundwater overdraft, exhausting unconfined aquifers. The socio-economic vulnerability of small and marginal farmers amplifies drought impacts into rural livelihood shocks. Mitigating this risk requires bridging structural deficits through decentralized water harvesting under MGNREGA, promoting climate-resilient micro-irrigation, and scaling solarized agricultural pumping through PM-KUSUM to optimize groundwater extraction.

Ecological and Economic Challenges of River Linking

The National River Linking Project (NRLP) seeks to correct spatial water imbalances by inter-basin transfers, but it faces profound ecological and economic trade-offs:

Ecological Challenges: Inter-basin diversions disrupt natural fluvial regimes, reduce downstream freshwater discharge, and impede sediment transport, accelerating deltaic degradation and coastal erosion in the Godavari, Krishna, and Mahanadi mouths. Reservoir inundation leads to severe forest fragmentation and biodiversity loss. For instance, the Ken-Betwa Link Project (KBLP) submerges substantial core habitat within the Panna Tiger Reserve. Inter-basin water transfers also alter water chemistry, temperature, and estuarine salinity, threatening endemic aquatic fauna.

Economic Challenges: Mega-diversions require massive capital investments that risk cost overruns and locked fiscal resources. Projects carry heavy Resettlement and Rehabilitation (R&R) costs alongside socio-environmental compensations. Riparian conflicts over surplus-versus-deficit basin classifications exacerbate inter-state federal disputes under Article 262. Furthermore, the massive recurring energy costs required for lift hydraulics challenge long-term benefit-cost viability when compared to decentralized watershed conservation.

A forward-looking policy must balance macro-engineering with localized ecological realities. Enhancing disaster resilience requires shifting from reactive structural fixes toward integrated river basin management (IWRM), nature-based slope stabilization, and decentralized micro-watershed development to ensure long-term ecological and water security.