Chapter 2 Physical Features Of India

Overview

India is characterized by a diverse range of physical features, including mountains, plains, deserts, plateaus, and islands. Geologically, the Peninsular Plateau is one of the oldest landmasses, while the Himalayas and the Northern Plains are the most recent formations. The chapter details the six major physiographic divisions of India:

The Himalayan Mountains

These young, fold mountains form India's northern border, stretching about 2,400 km from the Indus to the Brahmaputra. They are the world's loftiest and most rugged mountain barriers, with varying widths and greater altitudinal variations in the east. The Himalayas are divided into three parallel longitudinal ranges:

• Great or Inner Himalayas (Himadri): The northernmost and most continuous range, featuring loftiest peaks (average height 6,000m) and perennially snow-bound glaciers.
• Himachal or Lesser Himalaya: South of the Himadri, this rugged range consists of compressed and altered rocks. It is known for valleys like Kashmir, Kangra, and Kullu, and famous hill stations.
• Shiwaliks: The outermost range, composed of unconsolidated sediments, with altitudes varying between 900-1100m. Longitudinal valleys between the lesser Himalayas and the Shiwaliks are called Duns (e.g., Dehra Dun).

The Himalayas are also regionally divided by river valleys: Punjab (Indus-Satluj), Kumaon (Satluj-Kali), Nepal (Kali-Teesta), and Assam (Teesta-Dihang). Beyond the Dihang gorge, the Himalayas turn south, forming the Purvachal or Eastern hills, composed of sedimentary rocks and including the Patkai, Naga, Manipur, and Mizo hills.

The Northern Plains

Formed by the interplay of the Indus, Ganga, and Brahmaputra river systems and their tributaries, the Northern Plains are a vast, fertile expanse of alluvial soil covering about 7 lakh sq. km. They are densely populated and agriculturally productive. The plain is divided into sections:

• Punjab Plains: Formed by the Indus and its tributaries, largely in Pakistan.
• Ganga Plain: Extends between the Ghaggar and Teesta rivers, covering North India, UP, Bihar, Jharkhand, and West Bengal.
• Brahmaputra Plain: Lies primarily in Assam.

Within these plains, relief features are further categorized based on variations in their soil deposits:

• Bhabar: A narrow belt (8-16 km) parallel to the Shiwalik foothills, where streams disappear.
• Terai: A wet, swampy region south of Bhabar, formed by re-emerging streams, historically forested but now cleared for agriculture.
• Bhangar: Formed of older, higher alluvium, with calcareous deposits (kankar), presenting terrace-like features.
• Khadar: Newer, younger alluvial deposits of floodplains, renewed annually and highly fertile.

The Indus River system's tributaries form 'Doabs' (land between two rivers), and Punjab itself is derived from words meaning 'five waters'. Majuli, in the Brahmaputra, is the world's largest inhabited riverine island.

The Peninsular Plateau

This tableland is composed of ancient crystalline, igneous, and metamorphic rocks, formed from the breaking and drifting of the Gondwana landmass. It features broad, shallow valleys and rounded hills, divided into two main parts:

• Central Highlands: North of the Narmada river, including the Malwa Plateau. It is bounded by the Vindhyan range to the south and the Aravali hills to the northwest. Its eastward extensions are known as Bundelkhand and Baghelkhand, with the Chotanagpur Plateau marking the further eastern extension.
• Deccan Plateau: A triangular landmass south of the Narmada river, flanked by the Satpura range and extending eastwards as the Mahadev, Kaimur, and Maikal ranges. It is higher in the west and slopes gently eastward. The Meghalaya, Karbi-Anglong Plateau, and North Cachar Hills are eastward extensions separated by a fault. The Western Ghats and Eastern Ghats form the western and eastern edges, respectively.

The Western Ghats are continuous, higher (900-1600m), and cause orographic rain, with notable peaks like Anai Mudi. The Eastern Ghats are discontinuous, lower (600m), and dissected by rivers. The black soil area, known as the Deccan Trap, is of volcanic origin. The Aravali Hills, on the western margins, are highly eroded and extend from Gujarat to Delhi.

The Indian Desert

Located west of the Aravali Hills, this is an undulating sandy plain with sand dunes, receiving very low rainfall (below 150 mm/year). It has an arid climate with sparse vegetation. The Luni is the only significant river. Barchans (crescent-shaped dunes) are prominent, especially near the Indo-Pakistan border.

The Coastal Plains

These are narrow coastal strips flanking the Peninsular Plateau:

• Western Coast: Sandwiched between the Western Ghats and the Arabian Sea. It comprises the Konkan coast (north), Kannad Plain (central), and Malabar coast (south).
• Eastern Coast: Wider and level, along the Bay of Bengal. It is known as the Northern Circar (north) and Coromandel Coast (south). Major rivers like Mahanadi, Godavari, Krishna, and Kaveri form extensive deltas here. Lake Chilika is a significant feature on the eastern coast.

The Islands

India has two major island groups:

• Lakshadweep Islands: Located near the Malabar coast of Kerala, composed of small coral islands. Kavaratti is the administrative headquarters. It boasts diverse flora and fauna, with Pitti Island serving as a bird sanctuary.
• Andaman and Nicobar Islands: An elongated chain in the Bay of Bengal, extending north-south. They are larger, more numerous, and scattered, divided into the Andaman (north) and Nicobar (south). Believed to be elevated parts of submarine mountains, they have significant strategic importance and rich biodiversity, experiencing an equatorial climate.

Each physiographic division contributes to India's natural resource wealth, from the water and forest resources of the Himalayas to the agricultural productivity of the Northern Plains, mineral wealth of the Plateau, and fishing/port activities along the coasts and islands, all contributing to the country's development potential.

India And The World

India's central location at the head of the Indian Ocean is of immense strategic importance, facilitating trade and contact with the West and East. Its land routes through the northern mountains have historically fostered the exchange of ideas and commodities, contributing to cultural diffusion. The opening of the Suez Canal further enhanced its connectivity with Europe.

India’s Neighbours

India shares land boundaries with Pakistan, Afghanistan, China, Nepal, Bhutan, Myanmar, and Bangladesh. Sri Lanka and the Maldives are its island neighbors across the sea to the south.

Exercise

The exercises at the end of the chapter focus on reinforcing geographical knowledge. They include multiple-choice questions to test understanding of key terms like 'Peninsula', 'Purvachal', and coastal regions. Short answer questions require recalling specific geographical features like the Bhabar, divisions of the Himalayas, plateaus, and island origins. Students are also asked to distinguish between related geographical concepts like Bhangar/Khadar and Western/Eastern Ghats. Further questions require identifying and contrasting major physiographic divisions, detailing the Northern Plains, and writing short notes on specific features like the Indian Desert, Central Highlands, and Island groups. Map-based exercises guide students to locate various mountain ranges, peaks, plateaus, hills, deserts, and islands on an outline map of India.