Major Domains of the Earth Class 6 Notes CBSE Geography Chapter 5 [Free PDF Download]

Earth is the only planet that can support life. Because of the presence of life-sustaining materials such as land, air, and water, this is conceivable. The earth's constituents meet and interact on the surface of the planet. The Lithosphere is the earliest component of the earth. It is the solid portion of the earth on which we live, made up of dirt and rocks. The atmosphere is the earth's second realm. It's the gaseous layer that surrounds the planet. It is made up of gases such as oxygen, nitrogen, carbon dioxide, and others. The Hydrosphere is the earth's third domain. Water bodies and water in all forms, including ice, water, and water vapor, are included. The biosphere is a limited zone where land, water, and air collide, containing living organisms.

Lithosphere: 

• The solid section of the earth made up of rocks and soil is known as the lithosphere, and it is made up of rocks from the crust and layers of soil containing nutritional elements.

• The earth's surface is divided into vast landmasses known as continents and huge water bodies known as oceans, and these nutritional components sustain organisms on the planet. All of the world's oceans are linked.

• In all regions, the ocean level is the same. The elevation of the sea level is assumed to be zero, and elevations are calculated accordingly. From here, a variety of different places are measured.

• Mount Everest is the world's highest mountain peak with an elevation of 8,848 meters above sea level.

Continent: 

On the planet, there are seven continents separated by sea bodies. They are: 

Asia: Asia is the world's largest continent, covering one-third of the planet's total land area. It is located in the Eastern Hemisphere and is crossed by the Tropic of Cancer. The Ural Mountains separate Asia from the European continent. Asia and Europe's combined landmass has been given a name.

Europe: This continent is surrounded on three sides by the sea. It is located west of Asia and is significantly smaller than it. It is traversed by the Arctic Circle.

Africa: Africa is the world's second-largest continent and the only place on the planet where the Tropic of Cancer, the Equator, and the Tropic of Capricorn all pass through. Seas and oceans surround it. The continent's majority is located in the Northern Hemisphere. The Nile, the world's longest river, travels through Africa.

The Sahara, the world's largest and hottest desert, is located here.

North America: The Isthmus of Panama connects North America with South America. It is the world's third-largest continent, spanning both the Northern and Western Hemispheres.

South America: South America is located almost entirely in the Southern Hemisphere. The Andes, the world's longest mountain range, flows across it. It is crossed by the world's largest river, the Amazon.

Australia: Australia is the world's smallest continent, located entirely in the Southern Hemisphere. The island continent, as it is known, is bordered on all sides by oceans and water.

Antarctica: Antarctica is entirely located in the Southern Hemisphere. This continent's southern pole is located in the center. Antarctica is permanently covered in huge ice sheets and has no human settlements. In Antarctica, there are research stations. Maitri and Dakshin Gangotri are the names of two Indian research institutes.

Hydrosphere: 

• Because water covers more than 71 percent of the Earth, it is commonly referred to as the "blue planet." The hydrosphere is made up of water in all of its forms, including flowing water in rivers, oceans, and lakes, ice in glaciers, water vapor in the atmosphere, and subsurface water.

• The oceans make up 97 percent of the hydrosphere. This water is excessively salty for human consumption.

• A large portion of freshwater is found in ice sheets and glaciers, as well as subsurface water.

Oceans: 

• The earth's oceans make up the majority of the hydrosphere. They're all linked together.

• The ocean currents are always moving. Waves, tides, and ocean currents all-cause movement in the ocean.

• The Pacific Ocean, the Atlantic Ocean, the Indian Ocean, the Southern Ocean, and the Arctic Ocean are the world's oceans.

• The Pacific Ocean is the world's largest, covering one-third of its surface.

• Mariana Trench is located in the Pacific Ocean and is the deepest portion of the earth. It encircles North and South America, Asia, and Australia and is typically round.

• The Atlantic Ocean, the world's second-biggest ocean, is formed like an 'S' and is bordered on the east by Europe and Africa and on the west by North and South America.

• The Southern Ocean is found in the Southern Hemisphere and encompasses the Antarctic continent.

• The Arctic Ocean surrounds the north pole and is located within the Arctic Circle. The Bering Strait connects it to the Pacific Ocean.

Atmosphere: 

• The atmosphere is a blanket of air that surrounds the planet like a blanket and protects the biosphere from the destructive effects of sun rays.

• It stretches up to a height of 1600 kilometers and is separated into five layers. The basis on which leaves are divided is largely composition and temperature.

• Oxygen and nitrogen are the two major gases that make up the atmosphere. These two gases make up nearly all of the dry and clean air we breathe.

• The atmosphere contains 21 percent oxygen and 78 percent nitrogen. Other gases, like carbon dioxide and argon, make about 1% of the volume and are needed by living organisms for respiration. Nitrogen is required for plants and other living organisms to grow.

Biosphere: 

• The biosphere is the region where land, ocean, and air collide.

• Life can be found in the zone, and Earth is the only planet with a biosphere.

• There are a variety of organisms here, ranging from bacteria to massive animals.

• The biosphere is divided into two broad categories: plant kingdom and animal kingdom.

• The lithosphere, atmosphere, and hydrosphere have become unbalanced as a result of pollution and excessive use of earth resources.

• The air is polluted by emissions from industrial power plants, thermal power plants, and automobiles. Due to rising Carbon dioxide level, global warming is caused .

• Wastewater is poured into lakes and rivers, contaminating them.

• In many locations, agriculture and grazing have resulted in soil removal. Forest cutting has resulted in erosional processes, posing a threat to the lithosphere.

Important Questions and Answers

1. What are the four domains of the earth?

Ans: The earth's four domains are as follows: 

Lithosphere: The lithosphere is the rock and soil layer on which we all live.

Atmosphere: The atmosphere is a blanket of air that surrounds the world. It gives us oxygen to breathe and shields us from the sun's damaging rays.

Hydrosphere: Water in all forms, including flowing waters in rivers, oceans, and lakes, groundwater, and water vapor in the atmosphere, makes up the hydrosphere.

Biosphere: The biosphere is the domain of the earth where the other three domains come into contact. This domain is home to all living things. This is the only domain on the planet.

2. Despite being called the blue planet, earth faces a scarcity of water. Why?

Ans: The oceans contain 97 percent of the water in the hydrosphere. Ocean water is salty and unsafe for human consumption. A significant amount of freshwater is stored in glaciers and ice sheets among the remaining 3%, making them inaccessible to humans. As a result, the amount of water available for human consumption is highly limited. This is why, despite being known as the blue planet, freshwater for human consumption is scarce.

3. What do you understand by the term biosphere?

Ans: The biosphere is a small area of the earth where the other three domains of atmosphere, lithosphere, and hydrosphere interact. There are live beings in this domain. Only the planet Earth is home to this domain. Species of all kinds, from bacteria to massive animals, can be found here.

4. Why has there been an imbalance between the three layers of the earth?

Ans: Pollution and indiscriminate use of earth resources have contributed to an imbalance in the three domains of the hydrosphere, atmosphere, and lithosphere.

The air is polluted by emissions from automobiles, industrial power plants, and thermal power plants. Carbon dioxide levels in the atmosphere are rising, resulting in rising global temperatures and global warming. Water bodies are polluted by wastewater released into lakes and rivers from industrial and agricultural regions. In many areas, especially in hilly terrain, agriculture and grazing have resulted in soil removal. Forest cutting has resulted in erosional processes, posing a threat to the lithosphere. 

5. Write a short note on the Pacific and Atlantic oceans.

Ans: Pacific Ocean: The Pacific Ocean is the world's largest ocean. The Pacific Ocean is estimated to cover one-third of the Earth's surface. The Mariana Trench is located in the Pacific Ocean and is the world's deepest point. The Pacific Ocean, which surrounds North and South America, Australia, and Asia, is generally round.

Atlantic Ocean: The Atlantic Ocean, the world's second-biggest ocean, is formed like an 'S' and is bordered on the east by Europe and Africa and on the west by North and South America. The ocean's coastline is heavily indented and uneven. The Atlantic Ocean is the busiest in the world from a commercial standpoint because it provides the optimum location for natural harbors and ports.

6. Write briefly about the continents of the world.

Ans:

Asia: Asia is the world's largest continent, accounting for one-third of the planet's total land area. The Ural Mountains separate Asia from the European continent. Eurasia is the combined landmass of Asia and Europe.

Europe: Europe is a continent that is surrounded on three sides by the sea. Europe is located west of Asia and is significantly smaller than Asia. Europe is traversed by the Arctic Circle.

Africa: Africa is surrounded by seas and oceans on all sides. The continent's majority is located in the Northern Hemisphere. The Nile, the world's longest river, travels through Africa. The Sahara, the world's largest and hottest desert, is also located here.

North America: The Isthmus of Panama connects North and South America.

South America: South America is located almost entirely in the Southern Hemisphere. The Andes, the world's largest mountain range, extends from south to north through South America. The Amazon, the world's largest river, runs through it.

Australia: Australia is the world's smallest continent, located entirely in the Southern Hemisphere. The island continent, as it is known, is encircled on all sides by oceans.

Antarctica: Antarctica is a continent that surrounds the South Pole and is permanently ice-covered.

Short Details About the Major Domains of the Earth

Lithosphere: It consists of the solid layer of the earth on which the people live. The lithosphere consists of different landforms such as mountains, plateaus, valleys and so much more.

Atmosphere: Another part of the earth that comprises most of all the gaseous layers that tend to surround the earth is known as the atmosphere. Most components of the atmosphere include oxygen, carbon dioxide, nitrogen, and so much more. The main function of the atmosphere is to make sure that the earth is protected from the harmful UV rays and the heat of the sun.

Hydrosphere: This is the layer of the Earth which consists most of all the water bodies. The hydrosphere is known to cover about three-fourths of the entire planet and exists mostly in the form of several water bodies. Most of the common components of the hydrosphere consist of oceans, rivers, and other forms of water such as vapour, ice and so much more.

Biosphere: According to the Class 6 Geography Chapter 5, this is the domain of the earth which consists of all the different life forms such as plants, animals, microbes, and all the living things that exist in the environment. It is basically just a narrow zone in the environment where we can find water, land, as well as air altogether along with different life forms.

Lithosphere

The lithosphere can be defined as the solid layer which makes the earth. There are rocks and other materials in the earth’s crust which form this layer. Also, there are some other nutrients and elements which help in increasing the sustainability of the organisms. The earth's surface can be divided into 2 different forms. There are huge landmasses which can be called the continents and there are the water bodies which make up the oceans. There is an important connection between all the oceans in the world as the level of water always remains the same everywhere. The earth consists of 7 major continents known as Europe, Asia, South America, North America, Africa, Antarctica, and Australia.

Hydrosphere

We all know that the earth is also called the Blue plant. This is because of the presence of water bodies on the earth that cover about three-fourths of the entire planet. It is a known fact that water exists in about 71% of the entire planet. The hydrosphere is the domain of the earth that is composed mostly of water in all the different forms that it has. Most of the water bodies are in the form of oceans which are named as the Indian Ocean, The Pacific Ocean, the Arctic Ocean, the Atlantic Ocean, and the Southern Ocean. A very large portion of most water bodies tends to remain in the form of glaciers and ice sheets. Also, there are some water bodies which are utilized by humans and these are known as freshwater bodies.

Atmosphere

A certain layer of gas surrounds our entire planet which is known as the atmosphere. The atmosphere is responsible for providing the people with the air that they breathe. Not to mention that the major function of the atmosphere is to make sure that the harmful UV rays and the heat of the sun aren’t able to cause problems to the plants, animals, and other living beings. There are 5 different layers which divide the atmosphere. These layers begin from the surface of the earth and are differentiated based on their temperature and composition. The layers are known as Troposphere, Stratosphere, Mesosphere, Thermosphere, and Exosphere. Apart from that, the atmosphere is also home to many different gases such as Nitrogen, Oxygen, carbon dioxide, and others. 78% of the gases are Nitrogen, 21% are Oxygen and the rest of them are other gases.

Biosphere

The Biosphere is also described as the domain of life. It is a zone which is narrow and comprises all contact that happens between air, land, and water. This is the zone where all the living things exist and it is completely exclusive to this planet only. There are several species of different organisms that exist within the biosphere. Humans, plants, and other living organisms are the main components of the biosphere and the interactions that happen between them are also responsible for affecting the biosphere in a very crucial way.