Physiographic Regions of India

Physiographic Regions of India: 

Introduction

India’s physiographic landscape is an extraordinary diversity of landforms shaped over millions of years by tectonic forces, erosion, and climatic conditions. The nation can be divided into six major physiographic divisions based on their distinct physical features, geological composition, climate, and vegetation. Understanding these regions is crucial for comprehending India’s geography, resource distribution, settlement patterns, and environmental dynamics.

The six physiographic regions of India are:

1. The Northern and North-Eastern Mountains

2. The Northern Plains

3. The Peninsular Plateau

4. The Indian Desert

5. The Coastal Plains

6. The Islands

1. The Northern and North-Eastern Mountains

Overview and Extent

The Northern and North-Eastern Mountains comprise one of the most prominent physiographic features of India, extending approximately 2500 km in length and covering about 17% of India’s geographical area. These mountains are the youngest and loftiest mountain chains in the world, formed due to the convergence of the Indo-Australian (Indian) plate in the south and the Eurasian plate in the north.

Geological Formation

Formation History: Approximately 70 million years ago, the Indo-Australian plate separated from Gondwanaland and began moving towards the Eurasian plate at a speed of about 12 cm per year. This resulted in the contraction of the Tethys Sea—an ancient ocean that once occupied the region where the Himalayas now stand. The sediments deposited on the Tethys Sea bed, brought by rivers from the Tibetan plateau in the north and Gondwana land (Deccan Plateau) in the south, were compressed and folded. Since the Indian plate consisted of denser material than the Eurasian plate, it began to subduct beneath the Eurasian plate, causing massive lateral compression and folding of these sediments. This compression and folding occurred over three distinct phases spanning the last 50 million years, resulting in the formation of the Himalayas.

Key Point: The Himalayas are characterized by continuous uplift, as the Indian plate continues to move northward, causing the mountains to rise at a rate of approximately 1-2 cm per year.

Divisions of the Northern and North-Eastern Mountains

The Northern and North-Eastern Mountains are divided into three major groups:

A. The Himalayas

Extent and Structure: The Himalayas extend in an east-west direction, passing through 12 Indian states and forming a natural boundary with China and other neighboring countries. They exhibit tremendous altitudinal variations, with the eastern section showing greater variations than the western section.

Sub-divisions of the Himalayas:

The Himalayas are further subdivided into distinct ranges based on their latitudinal arrangement (from north to south):

1. Trans-Himalayas (Tibetan Himalayas)

• Located north of the Great Himalayan Range

• Stretch in an east-west direction for about 1,000 km

• Average elevation: approximately 3,000 meters above mean sea level

• Comprise the Karakoram Range, Ladakh Range, and Zaskar Range

Karakoram Range: The northernmost Trans-Himalayan range, forming India’s boundary with Afghanistan and China. It spans 110-130 km in width and houses some of the world’s highest peaks and largest glaciers. K2 (Mount Godwin-Austen), located in this range, stands at 8,611 meters and is the second-highest peak in the world. Other notable glaciers include the Siachen Glacier.

2. The Great Himalayan Range (Himadri)

• The most prominent and highest Himalayan range

• Contains the world’s highest peaks, including Mount Everest (8,848 m) and Kanchenjunga (8,586 m)

• Average elevation: 6,000-7,500 meters

• Characterized by perpetual snow and large glaciers

• Forms the main watershed of India

3. The Lesser Himalayas (Himachal)

• Located south of the Great Himalayas

• Average elevation: 1,500-4,500 meters

• Characterized by rugged terrain with deep valleys and gorges

• Major ranges include the Mussoorie, Nag Tiba, Pir Panjal, and Dhauladhar ranges

• Includes notable hill stations like Shimla and Darjeeling

• Narrow and closely aligned to the Great Himalayas

4. The Shiwalik Range (Outer Himalayas)

• The southernmost and youngest Himalayan range

• Average elevation: 900-1,500 meters

• Made of younger sediments (gravel, clay, silt)

• Runs parallel to the main Himalayas

• Forms the transition zone between mountains and plains

• Creates the ‘doons’ or ‘duns’—flat, fertile valleys between the Lesser Himalayas and Shiwalik range, the most famous being Dehra Dun

Regional Divisions of the Himalayas:

Based on longitudinal extent, the Himalayas are divided into four regional sections:

Punjab Himalayas (Western Himalayas)

• Located between the Indus River (west) and Sutlej River (east)

• Distance: approximately 560 km

• Spread across Jammu and Kashmir and Himachal Pradesh

• Also called Kashmir and Himachal Himalayas

• Major ranges: Karakoram, Ladakh, Pir Panjal, Zaskar, and Dhaola Dhar

• General elevation decreases towards the west

• All major rivers of the Indus system flow through this region

Kumaon Himalayas (Uttarakhand Himalayas)

• Located between the Sutlej River (west) and Kali River (east)

• Distance: approximately 320 km

• Spread across Uttarakhand

• The Lesser Himalayas are represented by the Mussoorie and Nag Tiba ranges

• The Shiwalik in this region runs between the Ganga and Yamuna rivers

• Notable features: flat valleys (duns/doons) between the Lesser Himalaya and Shiwalik range

Nepal Himalayas

• Located between the Kali River (west) and Tista River (east)

• Distance: approximately 800 km

• Most elevated section of the Himalayas

• Contains the highest concentration of peaks exceeding 8,000 meters

• Home to Mount Everest and Kanchenjunga

Assam Himalayas (Eastern Himalayas)

• Located between the Tista River (west) and Brahmaputra River (east)

• Distance: approximately 720 km

• Spread across Sikkim, Assam, and Arunachal Pradesh

• Elevation is much lesser than Nepal Himalayas

• Southern slopes are very steep; northern slopes are gentle

• The Himalayas take a sudden southward turn after the Dihang gorge, marking the transition to the Purvanchal

B. The Trans-Himalayan Ranges Beyond India

Hindu Kush: Located to the west of the Himalayas, extending from central and eastern Afghanistan into northwestern Pakistan. It stretches approximately 800 kilometers and forms the western section of the Hindu Kush Himalayan Region. The highest point is Tirich Mir (7,708 meters) in the Chitral District of Pakistan. The eastern end merges with the Karakoram Range.

C. The Eastern Hills or Purvanchal

Eastern Hills or Purvanchal are the southward extensions of the Himalayas running along the north-eastern edge of India. At the Dihang gorge, the Himalayas take a sudden southward bend, forming a series of comparatively low hills collectively called the Purvanchal. These hills are convex to the west and run along the India-Myanmar border from Arunachal Pradesh in the north to Mizoram in the south.

Sub-divisions of Purvanchal:

1. Patkai Bum (Patkai Range)

• Northernmost range of Purvanchal

• Located along the boundary between Arunachal Pradesh and Myanmar

• Composed of strong sandstone

• Elevation: 2,000-3,000 meters

• Merges into Naga Hills to the south

2. Naga Hills

• Located to the south of Patkai Bum

• Highest peak: Saramati (3,826 meters)

• Along with Patkai Bum, forms the watershed between India and Myanmar

• Elevation varies significantly

3. Manipur Hills

• Situated to the south of Naga Hills

• Separated from Naga Hills by the Barail Range

• General elevation: less than 2,500 meters

4. Jaintia, Khasi, and Garo Hills

• Located to the south of Manipur Hills

• Represent an eastward continuation of the Indian peninsular block

• Separated from the main block by the Ganga and Brahmaputra rivers

• Less elevated than other Purvanchal hills

5. Mizo Hills (Lushai Hills)

• Located to the south of Manipur Hills

• Elevation: less than 1,500 meters

• Highest point: Blue Mountain (2,157 meters) in the south

Significance of the Purvanchal: These hills extend southward through the Myanmar range (Arakan Yoma) to the Andaman and Nicobar Islands and even into the Indonesian archipelago, representing a continuation of the Himalayan orogeny.

Characteristics of the Northern and North-Eastern Mountains

• Youth and Loftiness: The youngest mountain chains, formed only a few million years ago, containing the world’s highest peaks

• Structural Complexity: Series of parallel or converging ranges separated by deep valleys, creating highly dissected topography

• Gradient Variation: Southern slopes have steep gradients; northern slopes have comparatively gentler slopes

• Rugged and Versatile: Vast, rugged landscape supporting remarkable cultural, ethnic, and biological diversity

• Snowfall and Glaciation: Perpetual snow and extensive glacier systems, particularly in the higher ranges

• Water Source: Acts as the source of major river systems including the Indus, Ganga, Brahmaputra, and their tributaries

• Biodiversity: Highly diverse flora and fauna, with forests ranging from tropical to alpine

Significance of the Northern and North-Eastern Mountains

• Climate Regulation: Acts as a natural barrier against cold winds from Central Asia, influencing India’s climate patterns

• River Systems: Source of major perennial rivers vital for irrigation and hydroelectric power

• Cultural Heritage: Home to diverse ethnic communities and ancient civilizations

• Economic Importance: Rich mineral resources, timber, and agricultural products

• Tourism and Recreation: Major tourist destinations with scenic beauty and adventure activities

• Biodiversity Hotspot: One of the world’s richest regions in terms of species diversity

2. The Northern Plains

Overview and Location

The Northern Plains represent the second-youngest physiographic region of India after the Indian Desert. They form one of the world’s most fertile and densely populated regions, created by the massive alluvial deposits of three major river systems: the Indus, Ganga, and Brahmaputra, along with their numerous tributaries.

Extent and Dimensions

• Length (west to east): approximately 2,400 kilometers

• Width (north to south): approximately 150-320 kilometers, varying in different sections

• Total Area: over 7 lakh square kilometers (700,000 sq km)

• Highest Point: Ambala in Haryana at 291 meters above sea level, which acts as a watershed between the Ganga and Indus river systems

Boundaries

• North: Shiwalik Range

• West: Indian Desert

• South: Peninsular Plateau

• East: Puruvachal (Eastern) Hills

Formation and Geological History

The Northern Plains were formed through the continuous deposition of alluvial sediments brought down by the three major river systems over millions of years. The gentle slope of these rivers (unlike the steeper gradients of rivers in peninsular India) allows for slow water flow, facilitating sediment deposition and creating thick alluvial layers.

Sub-divisions of the Northern Plains

The Northern Plains are divided into four distinct zones based on their surface features and age of deposits:

A. Bhabar Plains

• Location: Lies at the break in slope, forming a narrow band between the Shiwalik foothills and the Tarai region

• Width: approximately 8-16 kilometers (sometimes 8-10 km in certain sources), running parallel to the Shiwalik foothills

• Characteristics:

  • Consists of coarse alluvial deposits (pebbles, boulders, gravel)

  • Highly porous due to loose material

  • Streams and rivers originating in the mountains often disappear in this region due to high permeability

  • Heavy material (rocks and boulders) deposited by mountain streams

• Vegetation: Only giant trees with deep root systems can survive here

• Agricultural Potential: Unsuitable for cultivation due to coarse soil and lack of water retention

• Resources: Building materials are available in abundance

• Significance: Acts as a transitional zone between mountain and plain regions

B. Tarai Plains

• Location: Lies immediately south of the Bhabar region

• Characteristics:

  • Marshy, swampy, and wet region where streams reappear after disappearing in Bhabar

  • Underground water emerges to the surface

  • Highly saturated soil conditions

  • Thick natural vegetation, particularly forests

• Vegetation: Lush natural vegetation supporting a wide range of fauna, including dense forests

• Climate: High humidity and moisture

• Development History: These forests have been extensively cleared in states like Uttar Pradesh to make way for cultivation of wheat, rice, and sugarcane

• Ecological Importance: Biodiversity hotspot despite human interference

• Width: Varies but generally narrower than Bhabar

C. Bhangar Plains

• Location: Extends south of the Tarai region

• Area: Represents the largest portion of the Northern Plains

• Composition: Composed of the oldest alluvial soil among the four zones

• Soil Characteristics:

  • Dark-colored, calcium-rich alluvium locally known as kankar

  • Clay is the predominant soil type, though loam and sandy-loam can be found

  • Presence of saline and alkaline efflorescence known as Reh in dry areas

  • Calcium carbonate accumulations form nodular structures

• Topography: Lies above the flood plains of rivers and presents terrace-like features

• Agricultural Potential: Moderately suitable for agriculture but less fertile than Khadar

• Characteristics: Well-drained, stable surface

D. Khadar Plains

• Location: Forms the active flood plains adjacent to river channels

• Composition: Composed of newer, younger alluvial deposits from recent sedimentation

• Soil Characteristics:

  • Soil is renewed almost every year during flood season

  • Highly fertile due to fresh alluvial deposits

  • Fine textured, nutrient-rich soil

• Agricultural Significance: Ideal for intensive agricultural activities, supporting high-yield crops

• Seasonal Variation: Experiences annual inundation during monsoon periods

• Fertility: Among the most fertile agricultural lands in the world

E. Delta Plains

• Location: Where major rivers meet larger bodies of water (seas or oceans)

• Formation: As rivers slow down, they lose sediment load and spread out, creating delta formations

• Characteristics: Distinctive shapes including arcuate, cuspate, and bird’s foot deltas

• Significance: Highly fertile regions supporting dense populations and intensive agriculture

Regional Divisions of the Northern Plains

The Northern Plains are also divided into three major regional sections based on the river systems:

Punjab Plains

• River System: Formed by the Indus River and its tributaries (Jhelum, Chenab, Ravi, Beas, Sutlej)

• Location: Forms the western part of the Northern Plains

• Geographic Extent: Between the Indus in the west and Sutlej in the east

• Features:

  • Doabs abound in this region (Doab refers to the fertile land between two rivers)

  • Named doabs: Bist Doab, Rachna Doab, Jech Doab, etc.

• Distribution: A major portion lies in Pakistan; Indian portion is in Punjab and Haryana

• Agricultural Significance: Highly productive agricultural region

Ganga Plains

• River System: Formed by the Ganga River and its tributaries

• Location: Extends between the Ghaggar River (west) and Tista River (east)

• Geographic Features:

  • Northern edge of Rajmahal Hills to Meghalaya Plateau

  • Formed by downwarping of a portion of Peninsular India

  • Sculptured by sedimentation of Ganga and Brahmaputra rivers

• Topographic Features:

  • Levees (natural embankments along river channels)

  • Abandoned paleochannels (old river courses)

  • Distinct regions: Bhabar, Tarai, Bhangar, and Khadar plains

• River Characteristics: Continuous shifting of river courses, making the region prone to periodic floods

  • Kosi River in Bihar earned the notorious epithet “Sorrow of Bihar” due to its destructive flooding

• States Covered: Haryana, Delhi, Uttar Pradesh, Bihar, parts of Jharkhand, and West Bengal

• Ganga-Brahmaputra Delta:

  • Largest delta globally

  • Includes the tidal woods of the Sunderbans (World’s largest mangrove swamp)

  • Unique ecosystem supporting diverse wildlife including crocodiles and Royal Tigers

Brahmaputra Plains

• River System: Formed by the Brahmaputra River and its tributaries

• Location: Forms the eastern part of the Northern Plains

• Geographic Extent: Located in Assam state

• Characteristics:

  • Less developed compared to Ganga and Indus plains in terms of agricultural intensity

  • Important region for tea cultivation

  • Subject to severe seasonal flooding

Characteristics of the Northern Plains

• Alluvial Composition: Entirely composed of alluvial deposits from river systems

• Gentle Slope: Rivers flow with gentle gradient, facilitating sediment deposition

• Fertility: Among the world’s most fertile regions due to fresh alluvial deposits

• Population Density: Extremely high population density due to fertile soil, abundant water, and favorable climate

• Climate: Moderate, with adequate rainfall during monsoon season

• Vegetation: Originally forested, now mostly cultivated

• Economic Importance: Agricultural backbone of India

Agricultural and Economic Significance

• Crop Production: Major producer of wheat, rice, sugarcane, pulses, and oil seeds

• Population Support: Supports approximately 40% of India’s population on about 20% of its land area

• Urban Development: Contains major cities including Delhi, Lucknow, Patna, and Kolkata

• Economic Hub: Generates significant portion of India’s national income

3. The Peninsular Plateau

Overview and Characteristics

The Peninsular Plateau, also known as the Deccan Plateau or Indian Peninsular Plateau, represents one of the most ancient landmasses on Earth. It is the largest physiographic division of India by area and constitutes one of the oldest and most stable geological features of the country.

Extent and Area

• Total Area: approximately 16 lakh square kilometers (1.6 million sq km), representing approximately 50% of India’s total area

• Geographic Boundaries:

  • Base (North): Southern edge of the Indo-Gangetic Plains, approximately from Gujarat to West Bengal

  • Apex (South): Kanyakumari (Cape Comorin), India’s southernmost point

  • West: Western Ghats mountain range

  • East: Eastern Ghats mountain range

Geological Composition and Age

• Rock System: Primarily composed of Archaean gneisses and schists (very ancient igneous and metamorphic rocks)

• Tectonic Origin: Part of the Gondwanaland (an ancient supercontinent that broke apart millions of years ago)

• Age: One of the oldest landforms of Earth, largely composed of rocks billions of years old

• Stability: A highly stable shield block that has undergone little structural change since its formation

• Land History: Has remained a land area for several hundred million years, never submerged beneath the sea except in a few localized areas

• Evolutionary Significance: Represents a peneplain—an extensively eroded plateau that has been gradually reduced to a low relief through prolonged erosion

Physiographic Features

• Shape: Roughly triangular, with the broad base in the north and tapering to Kanyakumari in the south

• Average Height: 600-900 meters above sea level (varies from region to region)

• Surface Characteristics: Aggregation of several smaller plateaus, hill ranges interspersed with river basins and valleys

• Topography: Undulating landscape with elevation variations, particularly higher in the north and lower in the south

River Drainage Pattern

• General Slope: Slopes from west to east, indicating the general direction of water flow

• Drainage Direction: Most peninsular rivers flow from west to east, draining into the Bay of Bengal

  • Major east-flowing rivers: Godavari, Krishna, Mahanadi, Cauvery, Penner

• Exceptions: Narmada and Tapti rivers flow from east to west

  • These flow is caused by rift formation from divergent tectonic plate boundaries in the region

  • Form deep, gorge-like valleys as they flow through the plateau

• River Characteristics: Rivers create extensive river basins and have carved deep valleys through the plateau

Boundaries of the Peninsular Plateau

• Northern Boundary: The Satpura, Maikal Range, and Mahadeo hills

• Western Boundary: Western Ghats

• Eastern Boundary: Eastern Ghats

• Southern Boundary: Extends to the southern tip at Kanyakumari

Sub-divisions of the Peninsular Plateau

The Peninsular Plateau comprises numerous smaller plateaus and plateaus subdivisions:

A. Major Plateaus

1. Marwar Plateau (Mewar Plateau or Upland of Eastern Rajasthan)

• Location: Located to the east of the Aravali Range in eastern Rajasthan

• Elevation: 250-500 meters above sea level, sloping downwards eastwards

• Geological Composition: Made up of sandstone, shales, and limestones of the Vindhayan period

• River System:

  • Banas River originates in Aravali Range with tributaries Berach and Khari

  • These rivers flow towards the northwest and merge into the Chambal River

  • Erosional activity creates a rolling plain appearance

• Topography: Rolling plain (having slight rises and falls in land form)

2. Central Highland (Madhya Bharat Pathar or Madhya Bharat Plateau)

• Location: East of the Marwar or Mewar Upland

• River System: Largely composed of the Chambal River basin, flowing in a rift valley

• Tributaries: Kali Sindh, Banas, Parwan, and Parbati rivers

• Topography: Gently undulating plateau with rounded hills of sandstone

• Notable Feature: Chambal River ravines or badlands in the northern section

• Vegetation: Thick woodlands cover the region

3. Bundelkhand Upland (Bundelkhand Plateau)

• Location: Between the Yamuna River in the west and the Vindhyan Scarplands in the east

• Geological Composition: Old dissected upland made of Bundelkhand gneiss (granite and gneiss)

• Extent: Comprises four districts in Madhya Pradesh and five in Uttar Pradesh

• Characteristics: Granite and sandstone hillocks

• Topography: Undulating (wave-like) surface due to erosive activity of rivers

• Agricultural Significance: Unsuitable for farming due to rugged terrain

• Rivers: Betwa, Dhasan, and Ken rivers traverse the region

4. Malwa Plateau

• Location: Central India, bounded by Aravali Range in the west, Vindhyan Hills in the south, and Madhya Bharat Pathar in the north

• Shape: Generally triangular

• Geological Composition: Composed of huge lava flows, covered in black soil

• River Systems:

  • Narmada, Tapti, and Mahi rivers drain westwards to the Arabian Sea

  • Chambal and Betwa rivers drain northwards to join the Yamuna and enter the Bay of Bengal

  • Ken and upper courses of other rivers drain to Bay of Bengal

  • Northern section drained by Chambal and its right-bank tributaries (Kali, Sindh, Parbati)

• Distinctive Features: Chambal ravines in the northern section

• Topography: Sloping surface traversed by rivers

• Soil: Covered in black soil, highly suitable for cotton cultivation

5. Chhattisgarh Plain

• Location: Eastern region of Peninsular Plateau

• Shape: Saucer-shaped depression

• Drainage: Drained by the upper stretch of the Mahanadi River

• Geographic Setting: Situated between the Hills of Odisha and the Maikala Range

• Geological Structure: Laid with nearly horizontal beds of limestone and shales

• Character: Basin formation with gentle topography

6. Telangana and Rayalaseema Plateaus

• Location: Southern part of the Peninsular Plateau, including parts of Telangana and Andhra Pradesh

• River Systems: Drained by three major river systems—Godavari, Krishna, and Penner

• Physiographic Character: Composed of Ghats and peneplains

• Topography: Varied relief with hills and plains

7. Maharashtra Plateau

• Location: Northern part of the Deccan Plateau in Maharashtra state

• Geological Composition: Primarily composed of basaltic rocks created by lava flows

• Formation History: Created by the Deccan Traps (horizontal lava sheets) from massive volcanic eruptions at the end of the Cretaceous period (66 million years ago)

• Topography: Step-like topography from horizontal lava sheets, appearing as a rolling plain due to weathering

• River Systems: Broad and shallow basins of Godavari, Bhima, and Krishna rivers

• Distinctive Features: Flat-topped, steep-sided hills and mountains

• Soil: Regur soil (black cotton soil) covers the whole region

8. Karnataka Plateau

• Location: Central region of the Deccan Plateau

• Characteristics: Elevated plateau region with mixed topography

Major Hill Ranges of the Peninsular Plateau

A. Western Ghats (Sahyadri Range)

• Extent: Stretch from Mount Abu in Gujarat to Kanyakumari in Kerala, a distance of approximately 1,600 kilometers

• Orientation: Run parallel to the western coastline from north to south

• Width: Average width about 50-100 kilometers, but vary in different sections

• States Covered: Gujarat, Maharashtra, Goa, Karnataka, and Kerala

• Local Names:

  • Sahyadri in Maharashtra

  • Nilgiri Hills in Karnataka and Tamil Nadu

  • Anaimalai Hills (Elephant Mountains) in Tamil Nadu and Kerala

  • Cardamom Hills in Kerala

• Continuity: Continuous escarpment with few passes

• Elevation: 600-1,200 meters average; even higher in the south

• Highest Peak: Anamudi (2,695 meters) located on the Anaimalai Hills in Kerala, representing the highest point of the Peninsular Plateau

• Other Major Peaks: Dodabetta (2,637 m) on Nilgiri Hills

• Geological Composition: Part of block mountains with tilted structure, currently undergoing further upliftment

• Rock System: Charnockite

• Watershed Importance: Acts as the most important watershed in southern India

• River Systems:

  • All major east-flowing rivers emerge from the Western Ghats but flow eastward

  • Short, swift rivers flow westward into estuaries: Tapti, Narmada, Mandovi, Zuari

• Rainfall: Receives 100cm+ rainfall annually all along the coast and western slopes

  • The 100 cm isohyte (line of equal rainfall) marks the crest of the Western Ghats

  • Windward side receives extremely heavy rainfall (over 150 cm) due to orographic effect

• Forests: Densely forested with lush vegetation

• Soil: Laterite soils found throughout

• Biodiversity: One of the world’s eight “hottest hotspots” for biological diversity

  • Host to 4,000+ species of flowering plants with 500+ endemics

  • Contains diverse fauna including lion-tailed macaques, Nilgiri tahr, Malabar civet, Indian bison, and endemic amphibians and birds

  • UNESCO World Heritage Site status

• Economic Importance: Source of valuable timber, cardamom, pepper, and other forest products

B. Eastern Ghats

• Extent: Stretch from Odisha in the north to Tamil Nadu in the south, covering approximately 1,750 kilometers

• States Covered: Odisha, Andhra Pradesh, Telangana, Tamil Nadu, and parts of Karnataka

• Continuity: Discontinuous and broken hill ranges, unlike the Western Ghats

• Breaks: Broken by major rivers including Mahanadi, Godavari, Krishna, and Cauvery

• Orientation: Run roughly north-south, parallel to the eastern coastline

• Elevation: 600-900 meters average (lower than Western Ghats in most places)

• Highest Peak: Arma Konda (Jindhagada) (1,680 meters) in Andhra Pradesh

• Other Notable Peaks: Shevaroy, Nallamala, Nagari, and Kalahandi ranges

• Geological Composition: Ancient fold mountains made of gneiss, khondalite, and Dharwar rocks

• Current Status: Mountains of denudation (heavily eroded)

• Rock System: Gneiss, Khondalite, Dharwar

• River Systems:

  • Major rivers originating from the Western Ghats cross the Eastern Ghats flowing eastward

  • Mahanadi, Godavari, Krishna, and Cauvery have cut through the Eastern Ghats

  • Most rivers drain into the Bay of Bengal

• Rainfall: Receives 60-100 cm annual rainfall (less than Western Ghats)

• Forests: Less forested than Western Ghats, mostly dry deciduous to moist deciduous forests

• Soil: Red and black soil prevalent

• Biodiversity: Moderate biodiversity with patches of rich flora and fauna, but significantly less than Western Ghats

• Fragmentary Profile: Due to broken nature, rivers have greater dominance over mountain terrain

C. Vindhya Range

• Location: Forms the northern boundary of the Peninsular Plateau

• Extent: Runs from Rajasthan in the west to Madhya Pradesh in the east

• Characteristics: Important watershed dividing northern and peninsular India

• Orientation: Runs roughly east-west

D. Satpura Range

• Location: South of the Vindhya Range

• Extent: Runs through Madhya Pradesh

• Characteristics: Important mountain range creating varied topography

E. Maikal Range and Mahadeo Hills

• Location: Northern boundary of the Peninsular Plateau

• Characteristics: Form part of the northern boundary system

Characteristics of the Peninsular Plateau

• Ancient Landmass: One of Earth’s oldest continuous landforms

• Geological Stability: Highly stable shield region with minimal structural changes

• Worn Topography: Extensively eroded surface representing a peneplain

• Varied Relief: Despite being a plateau, exhibits considerable relief variation

• Agricultural Potential: Diverse agricultural zones from fertile volcanic regions (Malwa, Maharashtra) to rocky, less fertile areas

• Mineral Wealth: Rich repository of minerals including iron ore, coal, manganese, and other valuable minerals

• Biodiversity: Supports diverse ecosystems with tropical forests in some areas and dry deciduous forests in others

• Population Distribution: Supports significant population, particularly in fertile regions

Significance of the Peninsular Plateau

• Mineral Resources: One of India’s primary sources of minerals (iron ore, coal, manganese, bauxite)

• Agricultural Production: Contributes significantly to India’s agricultural output, particularly cotton, sugarcane, and other crops

• River Systems: Home to major river systems crucial for irrigation and hydroelectric power

• Biodiversity: Supports diverse plant and animal species

• Economic Activity: Industrial and mining hub

• Water Resources: Sources of major rivers for irrigation

4. The Indian Desert

Overview and Nomenclature

The Indian Desert, commonly referred to as the Thar Desert or the Great Indian Desert, is one of the world’s major arid regions and represents one of India’s six physiographic divisions. The name “Thar” is derived from “Thul,” the local term for the sand ridges prevalent in the region.

Location and Extent

• Geographic Position: Located to the northwest of the Aravali Hills

• Primary Area: Western Rajasthan (approximately 85% of the desert lies in India)

• Extension: Extends to adjacent parts of Pakistan (approximately 15%)

• States Covered: Primarily Rajasthan; also present in parts of Gujarat, Punjab, and Haryana

• International Boundary: Acts as a natural barrier demarcating the border between India and Pakistan

• Total Area: Covers an area exceeding 200,000 square kilometers

Geological History and Formation

Ancient Past: The region was not always a desert. Evidence indicates that most of the arid plain was under the Tethys Sea from the Permo-Carboniferous period and was later uplifted during the Pleistocene age.

Evidence of Past Environment:

• Wood fossils at the Aakal fossils park dating back approximately 180 million years (Jurassic period)

• Marine deposits found around Brahmsar near Jaisalmer, confirming the region’s marine history

• Dry beds of ancient rivers (such as the Saraswati), indicating the region was once fertile and had regular water flow

Geological Classification: Although geologically part of the Peninsular Plateau region (composed of gneisses, schists, and granites), the desert appears as an aggradational plain on the surface.

Climate-Based Formation: The desert formation resulted from distinct climatic and geographical factors leading to low rainfall in western Rajasthan:

• Monsoon Deflection: Summer monsoon winds prefer an easterly trajectory, bypassing the western region

• Rain Shadow Effect: The Aravali Range and surrounding hills create a rain shadow, reducing precipitation

• Precipitation Gradient: Rainfall gradually diminishes from east to west, with the westernmost regions receiving minimal precipitation

Characteristics and Classification

The Indian Desert is divided into two main sub-regions based on aridity levels:

A. Marusthali (The True Desert or Dead Land)

• Definition: The proper desert region characterized by extreme aridity

• Climate: Arid climate with very low vegetation cover

• Topography:

  • Eastern part: Rocky with outcrops of gneisses, schists, and granites

  • Western part: Covered by shifting sand dunes that undergo continuous changes in shape and size

• Sand Characteristics: Aeolian (wind-deposited) sand accumulated over 1.8 million years

• Dune Types: Multiple types of sand dunes present:

  • Barchan (Barkhan): Crescent-shaped sand dunes sculptured by unidirectional wind action, widespread throughout the desert

  • Longitudinal Dunes: Running parallel to the wind direction

  • Star Dunes: Multi-directional dune patterns

• Sand Movement: Dunes are highly mobile due to strong winds that rise each year before the monsoon onset

• Plain Features: Interspersed with sandy plains and low barren hills called bhakars

• Name Derivation: Called “Marusthali” because of the harsh, lifeless character of the region

B. Bagar (Semi-Desert Region)

• Definition: The semi-desert area east of the Aravalli Range with semi-arid conditions

• Location: Lies between the Aravalli Range and the true desert (Marusthali)

• Topography:

  • Thin layer of sand coverage

  • Sandy plains and low hills

  • Less dramatic sand dune formations than Marusthali

• Drainage:

  • Southern section: Drained by the Luni River

  • Northern section: Contains numerous salt lakes

• Water Features: Salt lakes and playas (temporary lakes) with brackish water, which is a major source of salt extraction

  • Notable salt lakes: Sambhar, Kuchaman, Didwana, Pachpadra, Phalodi (Rajasthan), and Kharaghoda (Gujarat)

• Seasonal Streams: The Rajasthan Bagar region has numerous short seasonal streams originating from the Aravalli Range

• Fertile Patches: These streams support agriculture in some fertile patches called Rohi, providing localized agricultural opportunities

• Transitional Zone: Represents transition between desert and more humid regions

Major Features and Hydrography

A. River Systems

Luni River (The Primary River of the Desert)

• Significance: The only important river of the Indian Desert

• Origin: Originates in the Pushkar Valley of the Aravalli Range near Ajmer

• Character: A seasonal stream (not perennial)

• Flow Direction: Flows towards the southwest into the Rann of Kutch

• Drainage Function: Divides the Bagar region into northern and southern sections

• Northern Section (Thali or Sandy Plain): The region north of Luni is known as Thali or sandy plain

Inland Drainage Systems:

• Several streams in the region disappear after flowing a short distance

• Represent typical inland drainage pattern by joining lakes or playas

• Examples: Sambhar Lake and other salt water bodies

B. Salt Lakes and Water Bodies

• Salty Lakes: Receive rainwater during monsoon and evaporate during dry season

• Salt Source: Salt comes from the weathering of rocks in the region

• Notable Salt Lakes: Sambhar, Kuchaman, Didwana, Pachpadra, Phalodi (in Rajasthan), Kharaghoda (in Gujarat)

• Economic Importance: Major source of salt production

Climatic Characteristics

Climate Type: Arid and Subtropical

Temperature:

• Winter: Extremes can reach near-freezing (close to 0°C)

• Summer: Can exceed 50°C (extremely hot)

• Average: Temperature varies significantly with season

Precipitation:

• Annual Rainfall: 100 to 500 mm per year (very low)

• Seasonal Distribution: Almost all precipitation occurs during June to September (southwest monsoon period)

• Rainfall Gradient: Decreases from east to west

  • Eastern parts may receive up to 500 mm

  • Western Marusthali receives as low as 100 mm

• High Evaporation: High evaporation rates exceed precipitation in most areas

Wind Patterns:

• Strong winds characteristic of the region, particularly before monsoon onset

• Wind-blown Sand: Significant sand movement and dune migration due to wind action

Vegetation and Flora

• Sparse Vegetation: Very low vegetation cover due to aridity

• Adapted Plants: Specialized xerophytic (drought-adapted) plants suited to arid conditions

• Tree Species: Scattered trees like acacia, khejri, and other desert-adapted species

• Grass Cover: Limited grassland, mostly replaced by scrub vegetation

• Vegetation Gradient: Denser vegetation in the eastern Bagar region, sparser in western Marusthali

Fauna and Wildlife

• Desert-adapted Animals: Adapted to extreme temperatures and water scarcity

• Notable Species:

  • Desert foxes, jackals, and other small carnivores

  • Camels and other livestock

  • Desert birds and reptiles

  • Various insects and arachnids

Geographic Boundaries

Bordering Regions:

• West and Northwest: Indus River plain (irrigated areas of Pakistan)

• North and Northeast: Punjab Plain

• Southeast: Aravalli Range (forms a natural boundary)

• South: Rann of Kachchh (salt marsh)

Subdivisions within the Desert

Regional Classifications:

• Wet Desert: Eastern parts receiving more rainfall (up to 500 mm)

• Dry Desert: Western Marusthali receiving minimal rainfall (100 mm)

• Rocky Outcrops: Eastern sections with exposed bedrock

• Sand Dune Regions: Western sections dominated by sand formations

Economic and Ecological Significance

• Agricultural Potential: Limited agricultural activity in Bagar region; major portions unsuitable for cultivation

• Salt Production: Major source of salt extraction from salt lakes

• Pastoral Activities: Limited grazing in semi-desert Bagar region

• Mining: Potential for mineral extraction

• Tourism: Desert tourism and adventure activities

• Strategic Importance: Border region with strategic and defense significance

Human Settlement and Land Use

• Sparse Population: Very low population density in desert proper

• Settlement Pattern: Concentrated around water sources (wells, oases)

• Traditional Lifestyle: Nomadic and semi-nomadic pastoral communities

• Modern Development: Limited modern agricultural and industrial development

• Challenges: Water scarcity remains the primary challenge for human settlement

Significance of the Indian Desert

• Natural Barrier: Separates India from Pakistan

• Climate Regulator: Influences regional and continental climate patterns

• Unique Ecosystem: Represents a distinct physiographic region with specialized flora and fauna

• Economic Resources: Salt production and limited mineral resources

• Cultural Heritage: Home to unique traditional communities and cultural practices

5. The Coastal Plains

Overview and Extent

The Coastal Plains of India refer to the stretches of narrow, flat, low-lying land situated along the Indian coastline, lying as a crucial interface between the peninsular plateau and the sea. These plains form one of the six major physiographic divisions of India and play vital roles in India’s economy, ecology, and culture.

Geographic Extent

• Total Length: Stretch for approximately 6,000-6,150 kilometers along the Indian coastline

• Mainland Coastline: 6,100 kilometers of mainland coastline

• Island Coastlines: Include the Andaman, Nicobar, and Lakshadweep islands

• Total Coastline: 7,516.6 kilometers including islands

• States/Union Territories: Touch 13 states and union territories

Geological Formation

Tectonic History: The straight and regular coastline of India resulted from the faulting of Gondwana land during the Cretaceous period (approximately 66 million years ago), when the supercontinent fragmented.

Coastal Plain Formation: These plains are formed by alluvial deposits from rivers and the action of sea waves, creating a transition zone between terrestrial and marine environments.

Major Divisions of Coastal Plains

The Coastal Plains are divided into two major parts that meet at the southernmost tip of India at Kanyakumari:

A. Western Coastal Plains

Location and Extent:

• Lie between the Western Ghats and the Arabian Sea

• Stretch from the Rann of Kutch (Gujarat) in the north to Kanyakumari in the south

• Distance: approximately 1,600 kilometers

Geographic Span:

• States Covered: Gujarat, Maharashtra, Goa, Karnataka, and Kerala

• Northern Boundary: Gulf of Cambay (Gulf of Khambhat)

• Southern Boundary: Cape Comorin (Kanyakumari)

Physical Characteristics:

• Width: Very narrow, averaging about 50-100 kilometers

• Narrower in Middle: Particularly narrow in the middle sections

• Broader Areas: Slightly broader in northern and southern parts

• Topography: Generally flat coastal strip

Coastline Type: Submergent coastline, resulting in indented shoreline with numerous natural harbors and creeks

Major Subdivisions (from north to south):

1. Konkan Coast

• Location: Covers the western coasts of Maharashtra, Goa, and northern Karnataka

• Extent: Northern section of Western Coastal Plains

• Characteristics: Highly dissected coastline with numerous creeks and inlets

2. Kanara Coast (Karavali)

• Location: Central section of Western Coastal Plains in Karnataka

• Characteristics: Intermediate region between Konkan and Malabar

3. Malabar Coast

• Location: Covers the western coast of southern Karnataka, Kerala, and southern Tamil Nadu

• Characteristics: Fertile coastal region with high rainfall

• Climate: Receives highest rainfall in India due to southwest monsoon

• Lagoons: Characterized by backwater lagoons and connecting lakes

• Fertility: Highly fertile region supporting diverse crops

River Systems:

• Short, swift rivers originating from Western Ghats

• Fast-flowing, perennial rivers flowing into estuaries

• Major rivers: Tapti, Narmada, Mandovi, and Zuari

• Form estuaries rather than deltas due to swift flow and short courses

• Rapid flow creates limited delta formation

Alluvial Composition: Made up of alluvium brought down by short streams originating from the Western Ghats

Coastal Features:

• Dotted with numerous coves (small bays), creeks, and inlets

• Submergent coastline provides natural conditions for port development

• Rocky promontories interspersed with sandy beaches

Natural Harbors: Abundant natural harbors facilitating maritime trade

• Notable: Mumbai, Kochi (Cochin)

Fertility and Agriculture:

• Except for the Malabar Coast region, much of the Western Coastal Plain is relatively infertile for agricultural purposes

• Limited agricultural productivity compared to eastern coast

• Rich in spices and plantation crops (coconut, spices)

Economic Significance:

• Major fishing centers

• Ports and maritime trade hubs

• Tourism destinations

• Coconut and spice cultivation

B. Eastern Coastal Plains

Location and Extent:

• Lie between the Eastern Ghats and the Bay of Bengal

• Extend from West Bengal in the north to Tamil Nadu in the south

• Distance: approximately 2,000+ kilometers

Geographic Span:

• States Covered: West Bengal, Odisha, Andhra Pradesh, Telangana, and Tamil Nadu

• Northern Boundary: Extends from West Bengal to the Ganges Delta region

• Southern Boundary: Extends to Kanyakumari

Physical Characteristics:

• Width: Generally wider and more level than Western Coastal Plains

• Breadth: Varies from narrow in north to broader in south

• Topography: More gently sloping than western coast

Coastline Type: Emergent coastline (also called risen coastline), resulting in a smooth, regular shoreline with fewer natural harbors

Major Subdivisions (from north to south):

1. Northern Circars (Northern Section)

• Location: Odisha and northern Andhra Pradesh

• Characteristics: Transitional zone with features of both northern and southern sections

• Extent: From Ganga Delta to approximately Krishna River

2. Coromandel Coast (Southeastern Section)

• Location: Covers the southeastern coast, primarily in Andhra Pradesh, Tamil Nadu

• Boundaries:

  • North: Utkal Plains

  • East: Bay of Bengal

  • South: Cauvery River

  • West: Eastern Ghats

• Extent: From Krishna River to Cauvery River

• Climate: Drier than western coast

• Characteristics: Known for its historic ports and maritime trade

3. Southern Section

• Location: Tamil Nadu and coastal areas south of Cauvery

• Characteristics: Transition to southern peninsular coastline

River Systems:

• Large rivers forming extensive, fertile deltas

• Delta formation: Rivers slow down and fan out into deltas, creating rich alluvial plains

• Major rivers: Mahanadi, Godavari, Krishna, and Cauvery

• These rivers create some of India’s most fertile agricultural regions

• Rivers flow from west to east, directly across the Eastern Ghats

Alluvial Characteristics: Made up of fertile alluvial deposits from major river systems

Lagoons and Lakes: Important water bodies

• Chilka Lake: Large lagoon on Odisha coast

• Pulicat Lake: Lagoon on Andhra Pradesh-Tamil Nadu border

• Various connecting lagoons and backwaters

Coastal Features:

• Smooth, relatively straight coastline due to emergent nature

• Sandy beaches more common than rocky shores

• Delta formations at river mouths

• Fewer natural harbors compared to western coast

Fertility and Agriculture:

• Highly fertile due to extensive river deltas and fresh alluvial deposits

• Best agricultural region on both coasts

• Crops: Rice (major staple), vegetables, coconut, spices

• Intensive agricultural activity

Economic Significance:

• Major agricultural production region

• Fishing centers

• Ports and maritime trade (though fewer natural harbors)

• Tourism destinations

• Rice and spice cultivation

Utkal Plains: Eastern coastal region in Odisha, sometimes identified as a distinct division

Comparative Features: Western vs. Eastern Coastal Plains

Ecological Importance

• Biodiversity Hotspots: Support diverse ecosystems

• Wetlands: Important for migratory birds and aquatic life

• Mangrove Forests: Particularly in deltas and estuaries

• Coral Reefs: Found in various coastal regions

Economic and Strategic Importance

• Trade Centers: Major maritime trade hubs with important ports

• Fishing Industry: One of India’s primary fishing regions

• Agriculture: Support high agricultural productivity in eastern plains

• Tourism: Popular tourist destinations

• Salt Production: Salt extraction from coastal areas

• Industrial Centers: Location of major industrial establishments

• Defense: Strategic importance for maritime security

Human Settlement and Development

• High Population Density: Densely populated regions

• Urban Centers: Location of major cities (Chennai, Kolkata, Visakhapatnam, etc.)

• Agricultural Communities: Farming communities in fertile delta regions

• Fishing Communities: Traditional and modern fishing populations

• Industrial Development: Significant industrial and manufacturing zones

Challenges and Issues

• Erosion: Coastal erosion affecting some regions

• Pollution: Marine and coastal pollution from industrial and urban centers

• Climate Change: Rising sea levels and increased cyclone activity

• Over-exploitation: Overfishing and resource depletion

• Urbanization Pressure: Uncontrolled urban expansion

Significance of Coastal Plains

• Economic Hub: Primary economic engine through agriculture, trade, and industry

• Population Center: Supports large urban and rural populations

• Agricultural Heartland: Major food production regions

• Maritime Gateway: Important for sea-based trade and commerce

• Biodiversity Reservoir: Important ecological region

• Strategic Location: Crucial for national security

6. The Islands

Overview and Geographic Significance

India has two major island groups situated in the Arabian Sea and the Bay of Bengal, along with several minor islands. These island territories are of significant strategic, economic, and cultural importance for India, extending the nation’s maritime jurisdiction and representing unique ecological systems.

Total Coastline Including Islands

• Island Coastlines: Contribute significantly to India’s total maritime boundary

• Total Indian Coastline: 7,516.6 kilometers including islands

• Mainland Coastline: 6,100 kilometers

• Island Contribution: Approximately 1,400+ kilometers from island territories

Major Island Groups

A. Andaman and Nicobar Islands

Location and Geographic Position:

• Located in the Bay of Bengal, approximately 1,200 kilometers from mainland India

• Geographic Coordinates: Lie between 6°45’N to 13°45’N latitude and 92°10’E to 94°15’E longitude

• Proximity: Located to the south of mainland and close to Myanmar (Burma)

• Distance from Mainland: Approximately 1,200 km from Calcutta

• Near Major Sea Routes: Close to the Malacca Strait and Ten Degree Channel

Island Composition:

• Total Islands: Composed of 265 islands (originally counted as 572 in some classifications)

  • Andaman Islands: Approximately 550 islands (203 major islands)

  • Nicobar Islands: Approximately 22 islands (62 major islands in some counts)

• Inhabited Islands: Only 37-38 islands are permanently inhabited

• Extent: Stretch for approximately 590 kilometers from north to south

Administrative Structure:

• Union Territory: Forms the Union Territory of Andaman and Nicobar Islands

• Capital: Port Blair located on South Andaman Island

Andaman Islands:

Geographic Features:

• Stretch north to south for about 800 kilometers

• Divided into three main island groups: North, Middle, and South Andaman

• Duncan Passage: Separates Little Andaman from South Andaman

• Great Andaman Group: Located in the north, separated from Nicobar group by the Ten Degree Channel

Major Islands:

• North Andaman: Contains the highest peak, Saddle Peak (737 meters)

• South Andaman: Contains Port Blair, the capital

• Middle Andaman: Central island group

• Havelock Island: Famous tourist destination known for beaches and water sports

• Radhanagar Beach: Popular beach on Havelock Island

Significant Channel:

• Ten Degree Channel: Important natural feature separating Andaman from Nicobar islands

Geographic Significance:

• Strategic location near Ten Degree Channel and Malacca Strait

• Important for maritime security and control of sea lanes

• Near major international shipping routes

Biodiversity and Ecology:

• Tropical Rainforests: Dense, biodiverse forests

• Coral Reefs: Fringed with coral reefs, supporting rich marine life

• Flora and Fauna:

  • Unique species found nowhere else

  • Andaman wild pig, saltwater crocodile, dugong

  • Diverse birdlife adapted to tropical environment

  • Endemic species of plants and animals

Indigenous Population:

• Great Andamanese: One of the tribal populations

• Onge: Indigenous tribe

• Jarwa: Semi-nomadic tribal group

• Sentinelese: Remote tribe with minimal outside contact, known for hostile behavior towards outsiders

• These groups represent unique human cultures and require special protection under Indian law

Development and Tourism:

• Established Settlements: Port Blair and other urban centers

• Tourism: Major tourist destination

• Infrastructure: Airports, ports, roads connecting major islands

• Popular Activities: Scuba diving, water sports, trekking, beach tourism

Nicobar Islands:

Geographic Features:

• Located south of Andamans, separated by the Ten Degree Channel

• Comprise a chain of islands stretching south from the Andamans

Major Islands:

• Great Nicobar: The largest island of the group

  • Located at the southernmost position

  • Very close to Sumatra island of Indonesia

  • Strategic position controlling sea lanes

• Car Nicobar: The northernmost island of Nicobar group

• Indira Point: India’s southernmost territorial point, located on Great Nicobar

  • Strategic Importance: India’s southernmost possession, giving sovereignty over vast maritime areas

  • Located near major international sea routes

Biodiversity and Ecology:

• UNESCO World Biosphere Reserve: Part of designated biosphere reserve

• Unique Species:

  • Nicobar pigeon: Endemic bird species

  • Coconut crab: Largest terrestrial crab species

  • Endemic flora and fauna found nowhere else

• Biodiversity: Rich and unique ecosystem

Indigenous Population:

• Nicobarese: Indigenous people with distinct culture and language

• Shompen: Semi-nomadic tribe living in interior forests

• Unique cultural heritage and traditions

Strategic Importance:

• Southernmost Possession: Indira Point represents India’s southern territorial limit

• Sea Lane Control: Close to major maritime routes

• Naval Base: Strategic importance for defense

Geological Characteristics:

• Rock Composition: Made of tertiary sandstone, limestone, and shale

• Base Formation: Resting on basic and ultrabasic volcanoes (similar to Himalayan geology)

• Volcanic Features:

  • Barren and Narcondam Islands (north of Port Blair): Volcanic islands

  • Only active volcanoes in India (no active volcanoes in mainland India)

  • Mountainous Terrain: Most islands are mountainous

• Coral Reefs: Many islands are fringed with coral reefs

B. Lakshadweep Islands

Location and Geographic Position:

• Located in the Arabian Sea, approximately 400 kilometers west of Kerala coast

• Located off the coast of Kerala

• Geographic Coordinates: Lie between approximately 8°N to 12°N latitude

• Proximity to Mainland: Closest to Kerala coast

Island Composition:

• Total Islands: 36 coral islands

• Inhabited Islands: Only 10 islands are inhabited

• Major Islands: Minicoy Island (largest), Androth, Amini, Kavaratti, Agatti

• Capital: Kavaratti (also written as Kavaratti)

Administrative Structure:

• Union Territory: Forms the Union Territory of Lakshadweep

• Independent UT: Separate from Kerala

Geographic and Geologic Characteristics:

• Coral Atolls: Composed entirely of coral formations

• Atoll Structures: Circular or oval coral islands with lagoons

• Seabed Origin: Built up from coral growth on submerged rocks

• Shallow Waters: Surrounded by shallow lagoons

• Reef Systems: Extensive coral reef systems

Ecological Features:

• Coral Ecosystems: Rich coral reef biodiversity

• Marine Life: Diverse fish species and other marine organisms

• Lagoon Ecosystems: Unique ecosystems within lagoons

• Tropical Vegetation: Coconut palms and tropical trees on islands

• Seabird Species: Various seabird species

Economic Importance:

• Fishing: Primary economic activity; rich fishing grounds

• Coconut Cultivation: Coconut plantations on inhabited islands

• Tourism: Emerging tourist destination with pristine beaches and diving

• Unique Products: Coconut oil and other coconut products

Cultural Significance:

• Muslim Population: Predominantly Muslim community with distinct culture

• Language: Malayalam and local dialects spoken

• Traditions: Unique marine-based cultural practices

Strategic Importance:

• Maritime Boundary: Extends India’s maritime exclusive economic zone (EEZ) significantly

• Sea Lane Control: Located on important sea routes

• Defense: Strategic location in Arabian Sea

C. Other Islands and Minor Territories

Minor Island Groups and Territories:

• New Moore Island (South Talpatti): Disputed territory between India and Bangladesh

• St. Martin’s Island: Located near Bangladesh

• Various smaller islands along both coasts

Comparative Features of Major Island Groups

Geographic and Strategic Significance of Islands

Maritime Jurisdiction:

• These islands extend India’s maritime boundary significantly

• Contribute to Exclusive Economic Zone (EEZ) claims

• Indira Point on Great Nicobar is India’s southernmost territorial point

Strategic Importance:

• Defense and Security: Important for naval defense and maritime security

• Sea Lane Control: Located on major international shipping routes

• Geopolitical Significance: Important in India’s regional strategy

• Malacca Strait: Close proximity important for controlling this strategic strait

• Myanmar Border: Islands serve as strategic eastern border markers

Biodiversity Significance:

• Unique Ecosystems: Harbor species found nowhere else

• Coral Reefs: Among the world’s most biodiverse ecosystems

• Tropical Forests: Rich tropical vegetation in Andaman-Nicobar

• Migratory Routes: Important stops for migratory birds

• Conservation: Several areas designated as protected areas and biosphere reserves

Economic Importance:

• Fishing Resources: Rich fishing grounds

• Tourism: Growing tourist destinations

• Agricultural Products: Coconut and other products from Lakshadweep

• Trade: Strategic positions for maritime trade

Environmental and Scientific Importance:

• Research Centers: Important for environmental and biodiversity research

• Climate Studies: Important for understanding Indian Ocean climate

• Marine Biology: Rich opportunities for marine research

Challenges and Conservation Issues

Andaman and Nicobar Islands:

• Population Pressure: Growing population affecting ecosystems

• Deforestation: Pressure from development and agriculture

• Tribal Protection: Need to protect indigenous tribal populations

• Infrastructure Development: Balancing development with conservation

• Cyclone Vulnerability: Prone to tropical cyclones and storms

Lakshadweep Islands:

• Climate Change: Rising sea levels threatening coral atolls

• Coral Bleaching: Warming waters affecting coral reefs

• Fishing Pressure: Over-exploitation of fish resources

• Population Concentration: Pressure on inhabited islands

• Limited Land Area: Constraint for development

Common Issues:

• Marine Pollution: Oil spills and ship-based pollution

• Plastic Waste: Accumulation of marine plastic debris

• Overfishing: Depletion of fish stocks

• Climate Vulnerability: Increasing cyclone and storm intensification

Cultural and Indigenous Heritage

• Tribal Communities: Andaman-Nicobar host unique tribal populations with distinct cultures

• Traditional Knowledge: Indigenous communities possess valuable environmental knowledge

• Legal Protection: Special constitutional provisions for tribal protection

• Cultural Preservation: Efforts to preserve unique cultural heritage

Significance of the Islands

• Political Sovereignty: Assert India’s territorial claims and maritime boundaries

• Economic Development: Future potential for tourism and fishing

• Biodiversity Conservation: Protect unique and endangered species

• Military Strategy: Defense and security infrastructure

• Scientific Research: Study unique ecosystems and species

• Climate Archives: Important for understanding historical climate patterns

Comparative Analysis of Physiographic Regions

Formation Age Comparison

Elevation and Topography Comparison

Climate Comparison

Vegetation Comparison