Introduction
The Aravalli range, dating back over a billion years to the Precambrian era, stretches approximately 700 km across Gujarat, Rajasthan, Haryana, and Delhi. Despite being one of the most degraded mountain systems in India, it remains central to water security, climate regulation, biodiversity conservation, and livelihood support in north and north-western India. The current policy moment exposes tensions between mineral exploitation, urbanisation, and ecological protection.
Why in the News
The Aravalli range has returned to public debate following a new definition notified by the Centre in October 2023, subsequently accepted by the Supreme Court in November, which excludes nearly 90% of the Aravalli landscape from protection against mining and development. This marks a sharp departure from earlier judicial and administrative approaches, which treated large parts of the range as ecologically sensitive regardless of formal forest classification.
How extensive is the Aravalli range and why does its geography matter?
- Spatial spread: Extends across four states and 37 districts, underscoring inter-state ecological interdependence.
- Length and distribution: Covers about 700 km, with 560 km located in Rajasthan alone, indicating uneven conservation pressures.
- Topographical role: Forms a physical barrier separating the Thar Desert from the Indo-Gangetic plains, limiting eastward sand movement.
Why are the Aravallis described as a natural sand and climate barrier?
- Desertification control: Blocks desert sand from advancing into Delhi, Haryana, and western Uttar Pradesh, reducing dust storms and land degradation.
- Air quality protection: Prevents sand ingress that worsens air pollution episodes in urban centres such as Delhi-NCR.
- Climate moderation: Acts as a climatic shield for north-west India, similar in function to the Western Ghats for peninsular India.
What role do the Aravallis play in groundwater recharge and river systems?
- Aquifer recharge: Rocky, fractured, and porous formations allow rainwater to percolate underground instead of surface runoff.
- Water security: Supports groundwater reserves for rapidly expanding urban centres such as Gurugram, Faridabad, and Sohna.
- River origins: Forms part of the watershed for rivers flowing into both the Arabian Sea and the Bay of Bengal, including tributaries linked to the Chambal system.
How does the Aravalli ecosystem support biodiversity and wildlife?
- Habitat diversity: Supports dry deciduous, semi-arid, and savanna ecosystems, enabling species adaptation in arid conditions.
- Protected areas: Hosts 22 wildlife sanctuaries, with 16 in Rajasthan alone.
- Tiger reserves: Includes Ranthambore, Sariska, and Mukundra, three of India’s critical tiger landscapes.
- Species presence: Supports fauna such as leopard, sloth bear, hyena, jackal, desert fox, and diverse avifauna.
What human activities are driving the degradation of the Aravallis?
- Mining and quarrying: Extensive legal and illegal extraction of stone and minerals, weakening hill structures.
- Deforestation: Reduces soil stability and accelerates erosion.
- Urbanisation: Expansion of cities like Gurugram and Alwar encroaches on hill systems and recharge zones.
- Ecological fragmentation: Creation of at least 12 major gaps in the range, enabling desert sand movement eastwards.
Why has the new Aravalli definition triggered concern?
- Regulatory dilution: Redefines Aravallis largely based on elevation and revenue records, excluding large ecologically active areas.
- Protection rollback: Removes mining and development restrictions from nearly 90% of the range.
- Ecological risk: Weakens safeguards for groundwater recharge zones and wildlife corridors.
- Governance gap: Shifts focus from ecosystem function to narrow land classification criteria.
Conclusion
The Aravalli range functions as a critical ecological infrastructure for northern India by regulating desert expansion, sustaining groundwater recharge, and supporting biodiversity across a densely populated region. The ongoing degradation of the range, driven by mining, deforestation, and regulatory dilution, undermines these life-supporting functions and amplifies risks of desertification, water stress, and ecological fragmentation. Ensuring landscape-level protection of the Aravallis is therefore essential not merely for environmental conservation, but for long-term economic resilience and human security in north and north-western India.
PYQ Relevance
[UPSC 2020] The process of desertification does not have climatic boundaries. Justify with examples.
Linkage: This question is relevant to GS-I (Physical Geography) as it examines desertification as a geomorphological and environmental process driven by both climatic and anthropogenic factors. The Aravalli degradation exemplifies how mining, deforestation, and urbanisation enable desert expansion beyond arid climatic zones, validating the non-climatic spread of desertification.