Chap 1: Geographical Diversity-NCERT Geography Notes Class 7 Social Science

Comprehensive Chapter-notes on the Geographical Diversity of India for Class 7 NCERT Social Science Book ‘Exploring Society Part 1’. Master India’s major physical divisions: Himalayas, Gangetic Plains, Peninsular Plateau, Thar Desert, Coastlines, and Islands for quick study and exam prep. #SirjiNotesC7

Chapter Notes on “Geographical Diversity of India” – Class 7 NCERT Social Science Book, “Exploring Society Part 1”

Introduction (Given in the beginning of the textbook)

Using the Physical Map of India

• A physical map shows natural features such as mountains, plains, plateaus, deserts, rivers, seas, and islands.
• Different colours on the map represent different heights (altitudes) of land.
  • Darker colours usually show higher regions like mountains.
  • Lighter colours show plains and low-lying areas.
• The legend (key) of the map helps us understand what each colour and symbol means.
• While studying this chapter, students should regularly refer to the physical map to locate places and landforms.

India’s Location and Size

• India is the seventh-largest country in the world.
• It is located in the continent of Asia.
• India, along with Pakistan, Bangladesh, Nepal, Bhutan, Sri Lanka, and Myanmar, forms the Indian Subcontinent.
  • It is called a subcontinent because it is a large and distinct part of a continent.

Major Physical Regions of India

For easy study, India is often divided into five major geographical regions:

• The Great Mountain Zone (Himalayas)
• The Plains of the Ganga and the Indus
• The Desert Region
• The Southern Peninsula
• The Islands

These regions together show the great geographical diversity of India. At this level, we study them in a broad and simple manner, without too many details.

Natural Boundaries of India

• The Himalayan Mountain Range forms a natural barrier in the north.
• The Thar Desert and the Arabian Sea lie in the west.
• The Indian Ocean lies to the south.
• The Bay of Bengal lies to the east.
• These natural features:
  • Separate India from other regions
  • Influence climate, culture, and history
  • Have helped shape India’s civilisation over time

Latitude, Longitude and Map Reading

• India lies roughly between:
  • 8°N to 37°N latitudes
  • 68°E to 97°E longitudes (approximate)
• Latitudes and longitudes help us:
  • Locate India accurately on the globe
  • Understand climate and time differences

Understanding Geographical Diversity

• A quick look at the physical map shows:
  • Snow-covered mountains
  • Vast fertile plains
  • Dry desert regions
  • Plateaus and coastal areas
  • Islands surrounded by seas
• The variety of colours on the map clearly indicates India’s varied relief and altitude.

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Main Notes: Chapter-Notes #SirjiNotesC7 based on the main text of Chapter 1: Geographical Diversity from the Class 7 NCERT Social Science book ‘Exploring Society Part 1’.

1. The Himalayas

Location and Extent

• The Himalayan Range stretches across the northern boundary of India like a massive natural wall.
• On the physical map, the Himalayas appear as a long, continuous mountain chain.
• By reading the map legend, we can see that:
  • Most Himalayan regions lie at very high altitudes
  • Several areas rise above 8000 metres

Height and Importance

• Many Himalayan peaks rise over 8000 metres and are collectively called the ‘Eight Thousanders’.
• The Himalayas extend across six Asian countries:
  • India, Nepal, Bhutan, China, Pakistan, and Afghanistan
• The highest mountain in the world, Mount Everest, is part of this range.

The Himalayas as the ‘Water Tower of Asia’

• During summer, snow melts in the Himalayas.
• This meltwater feeds major rivers such as:
  • Ganga
  • Indus
  • Brahmaputra
• These rivers and their tributaries:
  • Supply water for drinking
  • Support agriculture
  • Help in industrial activities
• Because they give rise to many important rivers, the Himalayas are called the ‘Water Tower of Asia’.

Cultural and Spiritual Importance

• The Himalayas are considered sacred in many belief systems.
• Numerous temples and monasteries are located here.
• The region attracts:
  • Pilgrims
  • Monks
  • Spiritual seekers from different parts of the world

1.1 Formation of the Himalayas

• Long ago, India was part of a large landmass called Gondwana, close to Africa.
• India slowly drifted northwards.
• About 50 million years ago, it collided with the Eurasian landmass.
• This collision caused the land between them to:
  • Crumple and fold, like a carpet pushed from one side
• This process led to the formation of the Himalayan Mountains.
• India is still moving northwards at about 5 cm per year.
• As a result, the Himalayas are still rising, growing about 5 mm each year.

Meaning of the Word ‘Himalaya’

• The word Himalaya comes from Sanskrit:
  • Hima = snow
  • Ālaya = abode
• Meaning: ‘Abode of Snow’

1.2 Main Ranges of the Himalayas

The Himalayas are divided into three major ranges:

1. Himadri (Greater Himalayas)

• Highest and most rugged range
• Includes peaks like Mount Everest and Kanchenjunga
• Remains snow-covered throughout the year
• Very harsh living conditions
• Few human settlements

2. Himachal (Lower Himalayas)

• Located south of the Himadri
• Has a moderate climate
• Rich in biodiversity
• Supports human habitation
• Famous hill stations include:
  • Nainital
  • Darjeeling
  • Shimla
  • Mussoorie

3. Shivalik Hills (Outer Himalayas)

• Lowest and outermost range
• Consists of rolling hills and dense forests
• Rich in wildlife
• Acts as a transition zone between:
  • The Himalayas
  • The Gangetic (Northern) Plains

Let’s Explore – Map Skill

Using physical and political maps, students can locate Himalayan states such as: Jammu & Kashmir, Ladakh, Himachal Pradesh, Uttarakhand, Sikkim, Arunachal Pradesh

Don’t Miss Out

Human Adaptation

• Traditional houses in the western Himalayas are built using kath-kuni or dhajji-dewari style.
• Made from local stone and wood
• These houses:
  • Keep interiors warm
  • Are resistant to mild earthquakes

The Great Himalayan National Park

• Located in Himachal Pradesh
• Known for rich biodiversity of plants and animals
• Declared a UNESCO World Heritage Site
• Conservation is carried out by:
  • The government
  • Local village communities

Exam Tip

• Remember the three Himalayan ranges in order:
  Himadri → Himachal → Shivalik
• Link the Himalayas with:
  • River systems
  • Climate
  • Culture
  • Natural protection of India

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2. The Cold Desert of India

Meaning of a Cold Desert

• Deserts are usually associated with hot and dry conditions.
• However, some deserts are extremely cold, and Ladakh is India’s cold desert.

Location and Climate

• Ladakh lies in the northern part of India, in the Himalayan region.
• It experiences:
  • Very low rainfall
  • Severe winters, with temperatures dropping below –30°C
• Due to the cold and dryness, vegetation is sparse.

Physical Features

• The landscape of Ladakh is:
  • Rugged and rocky
  • Marked by deep valleys
  • Dotted with lakes such as Pangong Tso
    • ‘Tso’ means lake
• The land surface resembles the surface of the moon, so it is called ‘moonland’.

Formation of the Terrain

• The terrain was formed when:
  • The Indian landmass collided with Eurasia
  • The rocks were folded and uplifted
• This region was once part of an ancient ocean.
• As a result:
  • Rocks are mainly made of sand and clay
  • Wind and rain erosion shaped the land into its present form

Flora and Fauna

• Despite harsh conditions, Ladakh supports unique wildlife, such as:
  • Snow leopards
  • Ibex
  • Tibetan antelopes

Life and Culture of the People

• The Ladakhi people live a simple and hardy life, adapted to extreme conditions.
• The region is known for:
  • Ancient Buddhist monasteries
  • Colourful festivals like:
    • Losar
    • Hemis Festival

Key Points for Exams

• Ladakh is a cold desert, not a hot one.
• Very low rainfall and extreme cold define the climate.
• The term ‘moonland’ refers to its unique landforms.
• Culture and lifestyle show human adaptation to geography.

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3. The Gangetic Plains

Location and Extent

• The Gangetic Plains lie south of the Himalayas.
• They form part of the Northern Plains of India.
• This region is vast, flat, and highly fertile.

Rivers and Soil Fertility

• The plains are nourished by major rivers originating from the Himalayas:
  • Ganga
  • Indus
  • Brahmaputra
• These rivers, along with their many tributaries:
  • Bring mineral-rich alluvium
  • Continuously renew the soil
• Due to this, the land is:
  • Extremely fertile
  • Ideal for agriculture
• The rivers are also used for generating electricity.

Role in Indian Civilisation

• The Gangetic Plains have been the heart of Indian civilisation for thousands of years.
• Easy availability of water and fertile land supported:
  • Early settlements
  • Growth of towns and cities
• Even today, a large proportion of India’s population lives in this region.

Agriculture and Economy

• Fertile soil allows:
  • Abundant agricultural production
  • Multiple cropping
• Agriculture forms the main livelihood of the people living here.

Transport and Communication

• The flat terrain of the Northern Plains has helped in developing:
  • Extensive road networks
  • Well-connected railway lines
• Rivers such as the Ganga and Brahmaputra have been used for:
  • Travel
  • Trade
  • Transport of goods for centuries

Don’t Miss Out – A Unique River

• Most Indian rivers are named after goddesses.
• Brahmaputra means ‘son of Brahma’.
• Unlike many rivers, it:
  • Becomes larger in summer
  • Because it is fed by melting Himalayan snow and monsoon rainfall

Let’s Explore – Thinking with Maps

The high concentration of lights in satellite images of the plains indicates:

• Dense population
• Large cities and towns
• Better transport and economic activity

Exam Tip

Always link the Gangetic Plains with:

• Rivers
• Fertile soil
• Dense population
• Development of civilisation and transport

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4. The Great Indian Desert (Thar Desert)

Location and Appearance

• The Thar Desert, also known as the Great Indian Desert, lies to the west of India.
• On the physical map, it appears as a yellowish region.
• It is marked by:
  • Vast stretches of golden sand dunes
  • Rugged terrain
  • A wide-open sky

Sand Dunes

• Sand dunes are hill-like formations made of sand.
• They are formed when:
  • Strong winds shift and deposit sand
  • Over time, the sand is shaped into mounds or hills
• Some dunes rise as high as 150 metres.
• Though made of sand, dunes have a distinct shape because wind constantly reshapes them.

Extent and Climate

• The Thar is a vast arid region.
• Most of it lies within India, covering parts of:
  • Rajasthan
  • Gujarat
  • Punjab
  • Haryana
• The climate is harsh, with:
  • Very high temperatures during the day
  • Cold nights
  • Scarcity of water

Role as a Natural Barrier

• Due to its extreme conditions, the Thar Desert:
  • Limits human and animal movement
  • Acts as a natural barrier in the western part of India

Life of the People

• People living in the Thar Desert have adapted their lifestyle to the environment.
• Their:
  • Food habits
  • Clothing
  • Daily practices
    are suited to conserve water and withstand heat.

Don’t Miss Out – Water Conservation

• Water is very scarce in the desert.
• Women often travel long distances to fetch water.
• Traditional practices include:
  • Cleaning utensils with sand instead of water
  • Reusing water after rinsing
• Rajasthan is famous for traditional water-harvesting systems, such as:
  • Taanka
  • Kunds
• These systems collect and store rainwater, often used for drinking.

Exam Tip

Remember the Thar Desert for:

• Sand dunes
• Harsh climate
• Water scarcity
• Human adaptation and conservation practices

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5. The Aravalli Hills

Age and Relief

• The Aravalli Range is among the oldest mountain ranges in the world.
• It is about 2.5 billion years old.
• The range consists of:
  • Many peaks and ridges
• Mount Abu is the highest peak, rising to over 1700 metres.
• Most hills of the Aravallis are moderate in height, between 300 and 900 metres.

Location

• The Aravalli Range stretches across several states:
  • Delhi
  • Rajasthan
  • Haryana
  • Gujarat
• A short journey can take one from:
  • Mount Abu in the Aravallis
  • To Jodhpur in the Thar Desert
• This shows how India’s geography changes sharply over short distances.

Role in Geography and Climate

• The Aravallis play an important role in northwestern India.
• They act as a natural barrier by:
  • Preventing the eastward expansion of the Thar Desert
• Thus, they help protect nearby regions from becoming desert-like.

Mineral Wealth

• The Aravallis are rich in valuable minerals, such as:
  • Marble
  • Granite
  • Zinc
  • Copper
• These minerals have supported:
  • Mining
  • Construction activities
    for many centuries
• Evidence from ancient mines at Zawar shows that:
  • Indians mastered zinc extraction over 800 years ago

Historical Importance

• The hills provided natural protection, making them ideal locations for forts.
• Famous forts located in the Aravallis include:
  • Chittorgarh
  • Kumbhalgarh
  • Ranthambore

Exam Tip

Remember the Aravallis for:

• Oldest mountain range
• Barrier against desert expansion
• Mineral resources
• Historic forts and human use

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6. The Peninsular Plateau

Meaning of a Plateau

• A plateau is a landform that:
  • Rises above the surrounding land
  • Has a mostly flat surface
  • Often has steep sides

Location and Shape

• India has several plateaus; the most important is the Peninsular Plateau.
• It lies in the middle and southern part of India.
• It has a triangular shape.
• It is a very old landform.
• Since it is surrounded by water on three sides:
  • Arabian Sea (west)
  • Bay of Bengal (east)
  • Indian Ocean (south)
• It is called a peninsular plateau.

Mountain Ranges Around the Plateau

• The plateau is bordered by:
  • Western Ghats
  • Eastern Ghats

Western Ghats

• Taller and more continuous than the Eastern Ghats
• Run along the western coast like a wall
• Many waterfalls flow down their steep slopes during the monsoon
• Declared a UNESCO World Heritage Site
• Known for:
  • Rich biodiversity
  • Source of many rivers
• The northern part is also called the Sahyadri Hills

Eastern Ghats

• Lower in height
• Broken into smaller and discontinuous hills
• Run along the eastern coast

The Deccan Plateau

• Lies between the Western and Eastern Ghats
• A vast area of flat highlands
• Forms the largest part of the Peninsular Plateau

Rivers of the Peninsular Plateau

• The plateau tilts slightly towards the east.
• Hence, many rivers flow from west to east and drain into the Bay of Bengal.
• Important east-flowing rivers include:
  • Godavari
  • Krishna
  • Kaveri
  • Mahanadi
• Some rivers flow westwards, such as:
  • Narmada
  • Tapti
• These rivers drain into the Arabian Sea.
• Rivers are important for:
  • Farming
  • Industries
  • Hydroelectric power

Natural Resources

• The Peninsular Plateau is rich in:
  • Minerals
  • Forests
  • Fertile land
• This makes it vital for India’s economy.

Tribal Communities

• Dense forests of the plateau are home to many tribal communities, such as:
  • Santhal
  • Gond
  • Baiga
  • Bhil
  • Korku
• These communities have:
  • Distinct languages
  • Unique traditions
  • A lifestyle closely connected to Nature
• Tribal populations are mainly found in:
  • Jharkhand
  • West Bengal
  • Odisha
  • Assam
  • Madhya Pradesh
  • Chhattisgarh
  • Maharashtra
  • Telangana
  • Gujarat

Waterfalls and Their Importance

• Rivers flowing over the uneven surface of plateaus form waterfalls.
• These waterfalls:
  • Attract tourists
  • Help in hydroelectric power generation
  • Provide water for irrigation

Exam Tip

Link the Peninsular Plateau with:

• Old landform
• Western & Eastern Ghats
• River flow direction
• Minerals, forests, and tribal life

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7. India’s Amazing Coastlines

Length and Natural Beauty

• India has a very long coastline, measuring over 7,500 km.
• The coastline is marked by:
  • Beautiful beaches
  • Rocky cliffs
  • Lush green forests
• Coastal regions show great variety:
  • Some beaches have golden sand
  • Others have black rocks
  • Some nearby islands have coral reefs
  • Others are covered with dense jungles
• This variety makes India’s coastline geographically rich and diverse.

Let’s Explore – Map-Based Understanding

• Many rivers flow into the Bay of Bengal, such as:
  • Ganga
  • Mahanadi
  • Godavari
  • Krishna
  • Kaveri
• India has coastal states along both coasts.
• When rivers split into many streams near the sea, it is called a delta.

7.1 The West Coast of India

Location

• The West Coast stretches from Gujarat to Kerala.
• It passes through:
  • Maharashtra
  • Goa
  • Karnataka

Rivers and Landforms

• Most rivers:
  • Originate in the Western Ghats
  • Are short and fast-flowing
• These rivers usually form estuaries rather than deltas.
• The coastline features:
  • Coves
  • Creeks
  • Estuaries
• The largest estuaries are formed by:
  • Narmada
  • Tapti

Economic Importance

• The west coast has many important ports and cities.
• These ports have been centres of:
  • Trade
  • Commerce
  • Economic activity
    for thousands of years

7.2 The East Coast of India

Location

• The East Coast lies between:
  • The Eastern Ghats
  • The Bay of Bengal
• It stretches from the Ganga delta in the north to Kanyakumari in the south.

Plains, Rivers and Deltas

• The east coast has wide and flat coastal plains.
• Many large rivers flow into the Bay of Bengal, such as:
  • Mahanadi
  • Godavari
  • Krishna
  • Kaveri
• These rivers form large and fertile deltas.

Lakes and Lagoons

• Important water bodies include:
  • Chilika Lake
  • Pulicat Lake
• A lagoon is a shallow body of water separated from the sea by a natural barrier.

Deltas and Agriculture

• Deltas are formed when rivers deposit sediments at their mouth.
• Over time, these sediments form triangular or fan-shaped landforms.
• The deltas of rivers like:
  • Godavari
  • Krishna
  • Kaveri
  • Mahanadi
• These areas are very fertile, making them ideal for farming.

Exam Tip

• West Coast → short rivers, estuaries, narrow plains
• East Coast → long rivers, deltas, wide plains

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8. Indian Islands

Meaning and Location

• Indian Islands are groups of islands spread across:
  1. Indian Ocean
  2. Arabian Sea
  3. Bay of Bengal
• They form an important part of India’s territory.
• India has two major island groups:
  1. Lakshadweep Islands – in the Arabian Sea
  2. Andaman and Nicobar Islands – in the Bay of Bengal

General Features

• These islands are known for:
  • Beautiful beaches
  • Coral reefs
  • Unique wildlife
  • Volcanic activity
• Several ancient tribal communities have lived here for tens of thousands of years.

8.1 Lakshadweep Islands

Location and Formation

• Lakshadweep is an archipelago located in the Arabian Sea.
• It lies close to the Malabar Coast of Kerala.
• It consists of 36 small islands, mostly coral islands.
• Not all islands are inhabited.

Importance

• India controls a large marine area around these islands.
• This helps in:
  • Fishing
  • Resource exploration
  • Environmental protection

8.2 Andaman and Nicobar Islands

Location and Structure

• This archipelago lies in the Bay of Bengal.
• It includes more than 500 large and small islands.
• The islands are divided into:
  • Andaman Islands
  • Nicobar Islands
• These islands are mostly volcanic in origin.

Strategic and Natural Importance

• Their location is strategically important.
• They act like India’s outposts, watching over sea routes.
• The islands have rich flora and fauna.

Historical Significance

• The Cellular Jail is located here.
• Many freedom fighters were imprisoned under harsh conditions.
• The jail has been preserved as a symbol of sacrifice and struggle for freedom.

Don’t Miss Out – Special Fact

• Barren Island, located in the Andaman and Nicobar Islands, is the only active volcano in India.
• It occasionally erupts, releasing smoke and lava.

Exam Tip

• Lakshadweep → Coral islands, Arabian Sea, near Kerala
• Andaman & Nicobar → Volcanic islands, Bay of Bengal, Cellular Jail

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9. The Delta in West Bengal and the Sundarbans

A delta is formed when a river slows down near the sea and deposits sediments. Over time, these deposits create a low-lying, triangular landform.

Location

• The Sundarbans are located in the delta region of:
  • Ganga
  • Brahmaputra
  • Their tributaries
• This region lies along the Bay of Bengal, on the eastern side of India.
• The delta spreads across two countries:
  • India (West Bengal)
  • Bangladesh

Special Features of the Sundarbans

• It has a unique landscape formed by:
  • Rivers
  • Sea water
  • Land
• The area is covered with dense mangrove forests.
• The Sundarbans is recognised as a UNESCO World Heritage Site.

Flora and Fauna

• It is home to a rich variety of wildlife.
• The most famous animal found here is the Royal Bengal Tiger.
• Mangrove trees help protect the coast from storms and floods.

Map Work Reminder

• Locate the Ganga–Brahmaputra delta on the physical map.
• Identify:
  • Bay of Bengal
  • West Bengal
  • The delta region shared by India and Bangladesh

Exam Tip

Sundarbans → Ganga–Brahmaputra delta, mangrove forests, UNESCO site, Royal Bengal Tiger

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10. The Hills of the Northeast

Location

• The hills of the Northeast are located in Meghalaya.
• These hills form part of the Meghalaya Plateau.
• The main hill ranges are:
  • Garo Hills
  • Khasi Hills
  • Jaintia Hills

Natural Features

• The region is known for:
  • Lush green landscapes
  • Heavy rainfall
  • Breathtaking waterfalls
• It receives one of the highest amounts of rainfall in the world.
• Due to abundant rainfall, the area has:
  • Dense forests
  • Fertile soil
  • Rich and unique wildlife

Climate and Environment

• Continuous rainfall supports:
  • Thick vegetation
  • Numerous streams and waterfalls
• The region plays an important role in maintaining ecological balance.

Don’t Miss Out – Special Example

• Mawlynnong Village, located in the East Khasi Hills, is known as the cleanest village in Asia.
• It is famous for:
  • Excellent cleanliness practices
  • Use of bamboo dustbins
  • Eco-friendly lifestyle
• The village is also known for living root bridges, formed by guiding tree roots over many years.

Map Work Reminder

• Locate Meghalaya on the political map.
• Identify:
  • Garo, Khasi, and Jaintia Hills
  • Nearby regions of Northeast India

Exam Tip

Meghalaya Plateau → Heavy rainfall, Garo–Khasi–Jaintia Hills, waterfalls, Mawlynnong

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