India: Physical Environment

1. Indian Physiography

India’s land is divided into distinct physiographic regions – each with unique terrain and significance. These include the Himalayan Mountains, the Northern Plains, the Peninsular Plateau, the Coastal Plains, and the Islands. Together, these regions form the varied landscape of India, from the highest peaks to fertile plains and extensive coastlines.

Himalayan Mountains (Northern Mountains)

• Features: Young fold mountains formed by the collision of the Indian and Eurasian plates. Stretch in a vast arc in the north (~2,400 km), with lofty peaks including Kanchenjunga (8,598 m, India’s highest peak). Consist of parallel ranges (Great Himalaya or Himadri, Middle Himalaya or Himachal, Outer Himalaya or Siwalik’s).
• Significance: Act as a natural barrier to cold winds from Central Asia, protecting India’s climate. Induce the monsoon rains by forcing moist winds to rise. They are the source of perennial rivers (Indus, Ganges, Brahmaputra) that feed the plains. Also rich in forests and biodiversity, and have strategic importance.

Northern Plains (Indo-Gangetic Plains)

• Features: Vast alluvial plains formed by deposition from the Indus, Ganga, Brahmaputra, and their tributaries. Stretch across north India from Punjab to Assam. Extremely flat, with fertile soils (newer alluvium khadar near rivers, older alluvium bhangra on slightly raised terraces).
• Significance: Among the most fertile and densely populated areas in the world. Well-suited for irrigation and intensive agriculture (rice, wheat, sugarcane, etc.) due to rich soil and abundant groundwater. Known as the food basket of India. The flat terrain enables infrastructure and urban settlement. These plains also form a corridor connecting India’s western and eastern regions.

Peninsular Plateau

• Features: The oldest and most stable landmass of India (a part of ancient Gondwanaland). A huge tableland in central and southern India, bounded by the Western Ghats (west) and Eastern Ghats (east). Composed of hard igneous and metamorphic rocks, with hill ranges like Aravalli (very old, eroded), Vindhya, Satpura, and the Deccan Trap region. Average elevation 600–900 m, with some peaks (e.g., Anaimudi 2,695 m in Western Ghats).
• Significance: Rich in minerals and resources (coal, iron, manganese, etc.) due to its geological history. Forms the core of the Indian peninsula, with stable terrain ideal for dams and mineral-based industries. The plateau’s rivers (e.g., Narmada, Godavari) have waterfalls and hydroelectric potential. Its diverse topography (valleys, uplands) supports varied crops and ecosystems, though soils are less fertile than in the plains.

Coastal Plains

• Features: Narrow plains along the coast flanking the Peninsular Plateau on east and west. The Western Coastal Plain (along the Arabian Sea) is relatively narrow (50-100 km wide) and divided into regions like Konkan and Malabar. The Eastern Coastal Plain (along the Bay of Bengal) is broader, with extensive river deltas (e.g., of the Mahanadi, Godavari, Krishna, Kaveri). Coastline length ~6,000 km.
• Significance: The coastal plains host many ports and harbors (e.g., Mumbai, Chennai) facilitating trade. The eastern plains’ deltas are fertile and support rice cultivation (the “Rice Bowl” of India). The western coast has lagoons and backwaters (Kerala) aiding inland navigation and fisheries. Both coasts support coconut, spices, and fishing-based economies and are important for tourism and tropical ecosystems (mangroves, beaches).

Islands

• Features: Two main island groups: Andaman and Nicobar Islands in the Bay of Bengal, and Lakshadweep Islands in the Arabian Sea. Andamans are a chain of over 300 islands (some volcanic, e.g., Barren Island) in the Bay of Bengal, dense with tropical forests. Nicobar group lies further south (close to the equator). Lakshadweep is a group of 36 coral atolls and islands off the south-west coast.
• Significance: These islands extend India’s territory into strategic sea lanes. Andaman & Nicobar Islands are rich in biodiversity (coral reefs, tropical rainforests) and home to indigenous tribes. They have strategic naval value (situated near the Malacca Strait) and growing tourism. Lakshadweep islands are known for their coral ecosystems and fisheries; they also attract tourists for their beaches and lagoons. Both island groups are important for India’s maritime security and Exclusive Economic Zone resources.