Eastern Ghats in Odisha
Overview and Extent
The Eastern Ghats constitute a discontinuous chain of mountains running parallel to the east coast of India, and in Odisha they form the most prominent physiographic feature separating the coastal plains from the interior tablelands. The range enters Odisha from Andhra Pradesh in the south and extends northeastwards through Koraput, Rayagada, Kalahandi, Kandhamal, Gajapati, Nayagarh, Mayurbhanj, and Keonjhar districts. Unlike the Western Ghats, the Eastern Ghats lack continuity and are broken by numerous river gaps, most notably the Mahanadi, Brahmani, Vansadhara, and Rushikulya rivers. These gaps have historically served as important corridors for transport and trade between the coast and the interior.
Major Peaks and Hill Ranges
The highest peak of the Eastern Ghats in Odisha is Deomali, standing at 1,672 metres in Koraput district, which is also the highest point in the entire state. Other notable peaks include Mahendragiri (1,501 metres) in Gajapati district, Sinkaram Gutta (1,620 metres), and Turiakonda (1,591 metres). The range is known by different local names along its length: the Niyamgiri Hills in Kalahandi, the Gandhamardan Hills in Balangir-Bargarh, the Malayagiri range in Angul, and the Similipal massif in Mayurbhanj. The Mahendragiri group of hills near the Andhra border is particularly significant, as it is associated with numerous mythological references in Hindu epics and represents the northern extremity of the Deccan Peninsula’s east-flowing drainage divide.
Geological Composition
The Eastern Ghats are composed primarily of the Eastern Ghats Granulite Belt, one of the oldest and most deeply eroded orogenic belts in India, with rocks dating back to the Archaean and Proterozoic eons. The dominant rock types include charnockites, khondalites, leptynites, and quartzites. The khondalites — garnet-sillimanite-graphite schists — are of particular economic importance as they host major deposits of bauxite and manganese. The bauxite cappings on these hills, formed by prolonged chemical weathering, constitute some of the largest bauxite reserves in Asia. The Niyamgiri Hills are a prime example, with high-grade bauxite deposits that have been at the centre of significant environmental and tribal-rights debates.
Biodiversity and Forest Cover
The Eastern Ghats harbour rich biodiversity, with forest types ranging from tropical moist deciduous to dry deciduous and semi-evergreen. The Similipal Biosphere Reserve in Mayurbhanj district is the most extensive protected area within this range, home to tigers, elephants, leopards, and the rare melanistic tiger. The Koraput-Kalahandi region is recognised as a centre of genetic diversity for rice, with hundreds of traditional varieties still cultivated by tribal farmers. The forests are dominated by sal, teak, bamboo, and a variety of medicinal plants. Several Important Bird Areas (IBAs) lie within this range, supporting populations of endemic and migratory species. However, mining, shifting cultivation, and deforestation have posed serious threats to the ecological integrity of the region.
Tribal Population
The Eastern Ghats are home to some of the most ancient tribal communities of India, including the Dongria Kondh, Kutia Kondh, Lanjia Saora, and Gadaba tribes. The Dongria Kondh of the Niyamgiri Hills are a Particularly Vulnerable Tribal Group (PVTG) whose livelihoods and culture are intimately tied to the hills and forests. These communities practise terraced agriculture, podu (shifting cultivation), and collection of non-timber forest products. The hills are integral to their spiritual beliefs, with many peaks and streams considered sacred. The interplay between tribal rights, forest conservation, and mineral extraction remains one of the most complex socio-political issues in this region.