Very Short Answer Questions

Q1. List out the factors affecting land use pattern of an area.
Ans1: Factors affecting the land use pattern of an area are:
Physical Factors: Climate, Topography, Water availability, Soil, Minerals, etc.
Human Factors: Population Density, Need & Desire of People, Cost, Development of Technology, etc.

 

Q2. Why is land use planning essential?
Ans2: Proper land use planning is essential for the optimum utilization of land.

 

Q3. In what different ways is land degradation caused?
Ans3: Common causes of land degradation are: Deforestation, Overgrazing, Urbanization, Dumping of Chemical Wastes, Excessive use of Fertilizers, Bad Farming Techniques, etc.

 

Q4. State the factors affecting soil formation?
Ans4: Factors affecting soil formation are: Relief, Parent Rock, Climate, Time and Organisms.

 

Q5. How water is called a renewable resource?
Ans5: Water is called renewable resource because it gets renewed through the process of Hydrological Cycle.

 

Q6. Suggest different ways to conserve water.
Ans6: Some of the important ways to conserve water are:
1. Decrease of water pollution
2. Proper irrigation method: Sprinklers and Drip irrigation can be used.
3. Water Harvesting Method
4. Water conservation in the home:

• Check faucets and pipes for leaks.
• Check your toilets for leaks.
• Use your water meter to check for hidden water leaks.
• Install water-saving shower heads and low-flow faucet aerators.
• Put plastic bottles or float booster in your toilet tank.
• Insulate your water pipes.
• Take shorter showers.
• Turn off the water after you wet your toothbrush.
• Use your dishwasher and clothes washer for only full loads.
• When washing dishes by hand, don't leave the water running for rinsing.

 

Short Answer Questions

Q7. What steps have been taken to conserve forest and wildlife?
Ans: Following are few steps that have been taken to conserve forest and wildlife:
(a) National Forest Policy framed by the government should be implemented.
(b) National Parks, Wildlife Sanctuaries, Bioreserves, Botanical Gardens have been setup.
(c) Special Projects (E.g. Project Tiger, Project Elephant, etc.).
(d) Celebration of Van Mahotsav.
(e) Every National festival is followed by tree plantation ceremony.
(f) Large scale afforestation or planting of tress is undertaken.
(g) Controlling of deforestation and overgrazing.
(h) Practices like shifting agriculture have been stopped.
(i) Social Awareness Programmes to be implemented.
(j) Wildlife Protection Act 1972.

 

Q8. Explain the difference between weathering and erosion.
Ans8:

 

Q9. Explain the different methods of soil conservation.
Ans9: Some methods of soil conservation are:
1. Mulching – Bare ground between plants is covered with a layer of organic matter like straw. It helps to retail soil moisture.
2. Contour Ploughing – Ploughing along contours can decrease the flow of water down the slopes.
3. Terrace Cultivation – Steps can be cut out on the slopes making terraces.
4. Strip Cropping – Strips of grass are grown between the crops. This breaks the force of wind.
5. Shelter Belts – Rows of trees are planted to create shelter. Thus, the speed of wind is reduced.
6. Rock Dam – Rocks are piled to slow the speed of wind.
7. Contour Barriers – Stones, grass and soil are used to make barriers. Trenches are made in front of the barriers to collect water.
8. Afforestation, Crop Rotation, Control over Deforestation and Overgrazing, etc.

 

Q10. State three points of differences between tropical evergreen and deciduous forests.
Ans10:

 

Long Answer Questions

Q11. Write a note on different types of soil.
Ans11: Different types of soil are:
1. Alluvial Soil:

•  It is the most important and most fertile type of soil found in India covering about 40 per cent of the total land area.
•  Soil is formed by the deposition of sediments brought down by the rivers.
•  The alluvial soil is found mostly in the Northern Plains and Coastal Plains of India.
•  The fine particles of sand, silt and clay are called alluvium. The alluvial soil can be divided into old alluvium, also called Bangar, and new alluvium, called Khadar.

2. Black Soil:

•  The black soil is also called the Black Cotton Soil. Cotton grows best in this soil.
•  Black soil is formed from the weathering of the igneous rocks.
•  The black soil is mostly found in the Deccan Trap, covering large areas of Maharashtra, Gujarat and western Madhya Pradesh. It is also found in some parts of Godavari and Krishna river valleys, covering parts of Karnataka, Andhra Pradesh and Tamil Nadu.

3. Red Soil:

•  Red soil is derived from the weathering of the igneous and metamorphic rocks.
•  The red colour is due to the high percentage of iron contents.
•  Red soil is found in the southern and eastern parts of the peninsular plateau.

4. Laterite Soil:

• The laterite soil is widely spread in India and is mainly found on the summits of the Western Ghats, Eastern Ghats, Rajmahal Hills, Vindhyas, Satpuras and Malwa plateau.
•  Due to intensive leaching, the laterite soil generally lacks fertility and is of low value for crop production. But when manured and timely irrigated, the soil is suitable for producing plantation crops like tea, coffee, rubber, coconut, etc.
• Leaching is a process in which heavy rains wash away the fertile part of the soil.

5. Mountain Soil:

•  The mountain soil is generally found on the hill slopes covered with forests.
•  This type of soil is found in the Himalayan region, the Western and Eastern Ghats and in some parts of the Peninsular India.
•  This soil is rich in humus, but poor in potash, phosphorus and lime.
•  This soil is especially suitable for producing plantation crops, such as tea, coffee.

6. Desert Soil:

•  The desert soil is found mostly in the arid and semi-arid regions, receiving less than 50 cm of annual rainfall.
•  Such regions are mostly found in Rajasthan and the adjoining areas of Haryana and Punjab. The Rann of Kachchh in Gujarat is an extension of this region.
•  The desert soil has sand (90 to 95 per cent) and clay (5 to 10 per cent).

 

Q12. Explain the reasons for water shortage or scarcity in a given region.
Ans12: Man uses water not only for drinking, cooking, washing, bathing, etc., but also for other activities like agriculture, industry, generation of hydroelectricity, navigation, etc.
Due to overpopulation, industrialization and urbanization, the consumption of water has increased manifold. Increased agricultural production to meet the growing needs of the population, modern lifestyle of the people and greater use of electricity in industries has resulted in water scarcity in many parts of the world. Above all the pollution of water bodies is due to irresponsible and reckless attitude of mankind. This has reduced the availability of fresh water for human consumption.

 

Q13. List out the causes for depletion of forest and wildlife.
Ans13: Deforestation, Overgrazing by animals, Forest fires, Hunting of animals, Industrialization, Urbanization, Increase in Population, etc. are some of the activities of the human beings, which has caused the depletion of forest and wildlife.

 

Q14. State four mitigation strategies to reduce the impact of landslides.
Ans14: Some of the mitigation strategies to reduce the impact of landslides are:
(a) Construction should be done using proper engineering methods.
(b) Constructing retaining walls.
(c) Improving drainage and slope management system.
(d) Proper land use planning.
(e) Afforestation.

 

Q15. How are forest fire caused? List out a few steps to prevent forest fire.
Ans15: Wildfires can be ignited by a variety of occurrences. In addition to lightning, human-related activities start a large number of fires every year. Unattended or out-of-control campfires, a discarded burning cigarette, arson, or even equipment use can set off a blaze.
Following are few steps to prevent forest fire:
1. Watch posts to be setup to prevent forest fire.
2. Modern fire fighting equipments and efficient communication technology should be used.
3. Timely detection of fire and air patrolling should be done.
4. Proper awareness among people and mock drill programmes to use fire extinguishers.
5. Be careful when smoking cigarettes in the forest. Extinguish them completely and do not throw butts near trees or dry leaves.
6. Completely extinguish your camp fire if you have been camping in the forest.
7. Avoid using fireworks in or near a forest.
8. Use caution when cooking on an open flame or grill in your backyard. Unattended fires can contribute to nearby forest fires.
9. Avoid spilling any industrial waste near forests. The wastes are normally toxic in nature and can prove to be one of the major causes of forest fires.

 

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Q1. Explain the importance of standard meridian of India.
Ans 1: The longitudinal extent of India is 30 degrees. The sun rises in the east and sets in the west, it takes 4 minutes for the sun to move across 1 longitude. Thus, the eastern most point of India would be 2 hours ahead of the western most point (30 x 4 = 120 minutes), in accordance with the local time. This difference in time might create confusion in air and rail timings and so many other things across the two states. To avoid this confusion a longitude passing through the midpoint of 68^o7' East (western most longitude) and 97^o25' East (eastern most longitude) is taken as the standard prime meridian of India. Thus, 82^o30' East longitude is taken as the Standard Time Meridian of India, as it passes through the middle of India (Mirzapur in Uttar Pradesh). With this same time is followed all over the country, making standard meridian of India very important for the smooth functioning.

 

Q2. Distinguish between Latitudes and Longitude.
Ans 2:

 

Q3. Describe the location and size of India.
Ans 3:
Size:

•  India is the seventh largest country in the world covering an area of 3.28 million square kilometers.
•  The country lies wholly in the Northern and Eastern hemispheres.
•  India covers 2.4 % of the total geographical area of the world.
•  The country is of a vast size and measures about 3,214 kilometers from North to South and about 2,933 kilometers from West to East.
•  Coastline: 7,516.6 km encompassing the mainland, Lakshadweep Islands, and the Andaman & Nicobar Islands.

Location:

•  The mainland stretches from Latitude 8^o4' North to 37^o6' North and from Longitude 68^o7' East to 97^o25' East.
•  The latitudinal & longitudinal extent of the country is almost same in degrees i.e. about 30 degrees.
•  The southernmost point in the Indian Territory, (in Great Nicobar Islands) is the Indira Point (6^o45'), while Kanya-kumari, is the southernmost point of Indian mainland.
•  Tropic of Cancer crosses the country at 23^o30' North dividing the country into almost two equal parts.
•  The 82^o30' East longitude is taken as Standard Time Meridian of India, as it passes through the middle of India (Mirzapur in Uttar Pradesh).
•  Indian Standard Time: GMT +05:30.

 

Q4. How is India connected to the world through the sea routes?
Ans 4: The Trans Indian Ocean routes which connect the countries of Europe in the West and the countries of East Asia provide a strategic central location to India. Note that the Deccan Peninsula protrudes into the Indian Ocean, thus helping India to establish close contact with West Asia, Africa and Europe from the western coast and with Southeast and East Asia from the eastern coast.
Since the opening of the Suez Canal in 1869, India's distance from Europe has been reduced by 7,000 kms.

 

Q5. How has land routes contributed in the exchange of ideas and commodities since ancient times?
Ans 5: The land routes have contributed in the exchange of ideas and commodities since ancient times. The ideas of the Upanishads and the Ramayana, the stories of Panchtantra, the Indian numerals and the decimal system thus could reach many parts of the world. The spices, muslin and other merchandise were taken from India to different countries. On the other hand, the influence of Greek sculpture, and the architectural styles of dome and minarets from West Asia can be seen in different parts of India.

 

Q6. Map Work:
(a) The Eastern and Western most Longitudes in degrees.
(b) The Northern and Southern most Latitudes in degrees.
(c) The southernmost point of Indian Mainland.
(d) The Standard Meridian of India
(e) The Island groups of India lying in the Arabian Sea and the Bay of Bengal.

Ans 6:

 

 

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Objectives and Goals:

• Natural Resource – Land, Soil, Water, Forest, etc.
• Land: the most important natural resource.
• Land use pattern (India and the World).
• Factors affecting the land use pattern.
• Land Degradation. Common causes of land degradation. Measures to control land degradation.
• Landslides and some mitigation strategies.
• Soil, factors of soil formation and the soil horizons.
• Different types of soils (i.e. Alluvial Soil, Black Soil, Red Soil, Laterite Soil, Desert Soil and Mountainous Soil).
• Degradation of soil and the methods used for the conservation of soil.
• Water, distribution of water bodies on the earth's surface, Hydrological Cycle.
• Problems related the availability water and the ways to conserve water.
• Natural Vegetation and Wildlife.
• Ecosystem, and distribution of natural vegetation in the world.
• Major natural vegetations of the world (i.e. Temperate Evergreen Forest, Temperate Deciduous Forest, Tropical Evergreen Forest, Tropical
• Monsoon Forest, Coniferous Forest, Mediterranean Forest Temperate Grassland, Tropical Grassland Tundra, Desert & Scrub).
• Depletion of forests and wildlife.
• Conservation of forests and wildlife.
• Mitigation strategies.

 

 

Important points to remember:

• Land is the most important natural resource.
• It covers only 29% of the total earth's surface and all this area is not habitable, rest 71% is covered with water bodies.
• 90% of the total world population resides in 30% of the land area and remaining 70% is uninhabitable or sparsely populated.
• Characteristics of land and climate are the two important factors for the uneven distribution of the population in this world.
• Areas having moderate climate, level land and fertile soil are the ideal conditions for the human habitation. These areas are densely populated because they support various economic activities.
• On contrary, rugged topography, steep slopes of mountains, low lying areas prone to water logging, deserts areas, thick forests are uninhabitable. These areas are less populated.

 

Land Use:  Different areas of the available land are used for different purposes like agriculture, forestry, mining, building houses, roads, industries, etc. this is called land use.

Factors effecting land use are: -

1. Climate            2. Topography            3. Water availability             4. Soil             5. Minerals

Population and Technology are also important factors of land use pattern.

 

Land can be divided on the basis of ownership:

1.   Private: This type of land is used by individuals, according to their needs.

2.  Common: Community land is used by people jointly for common use.

 

• LAND IS LIMITED BUT THE DEMAND IS INCREASING EVERYDAY.
• THE CHANGE IN LAND USE PATTERN SHOWS THE CHANGES IN THE SOCIETY.
• TODAY, SOIL EROSION, DEGRADATION OF LAND, LANDSLIDES, AND DESERTIFICATION ARE THE MAJOR THREATS TO THE ENVIRONMENT.

 

Land Degradation: 

It is the decline in the productive capacity of land for some time or permanently.

 

Common causes of land degradation are:

1. Deforestation

2. Overgrazing

3. Urbanization

4. Dumping of Chemical Wastes

5. Excessive use of Fertilizers

6. Bad Farming Techniques

 

Some of  the measures to control  land degradation are:

1. Constructing retention walls in the mountain areas to stop landslides.

2. Land Reclamation

3. Regulated use of chemical fertilizers and pesticides

4. Afforestation

5. Check on Overgrazing

6. Control of Mining Activities

 

Landslides:

Sliding of huge debris, rocks and other material down the slope is known as "Landslides". Landslides occur along with earthquakes, floods and volcanic eruptions.Landslides are common in mountainous regions and deep slopes.

 

Mitigation Strategies:

1. Construction should be done using proper engineering methods.

2. Constructing retaining walls

3. Improving drainage and slope management system

4. Proper land use planning

5. Afforestation

 

SOIL

• THE UPPERMOST LAYER OF THE EARTH'S CRUST IS KNOWN AS SOIL. IT IS MADE UO OF LOOSE ROCK FRAGMENTS AND HUMUS.

             (Humus is a dark coloured stable form of organic matter that remains after most of plant or animals' residues have decomposed).

• MOST OF THE FOOD ITEMS LIKE WHEAT, RICE, PULSES, FRUITS, VEGITABLES, ETC. ARE OBTAINED FROM PLANTS THAT GROW ON SOIL.

 

Factors of Soil Formation:

1. Relief – Altitude and slope determines the accumulation of soil.

2. Parent Rock – It determines, colour, texture, chemical properties, mineral contents, etc.

3. Climate – Rainfall and temperature influence rate of humus and weathering.

4. Time – It determines thickness of soil profile.

5. Organisms – Microorganisms and vegetation affect the rate of humus formation.

 

Soil Horizons:

Soil profile refers to the different layers of the soil. There are four different layers:

1. Top Soil:  It is the uppermost layer.Rich in humus and minerals.Consists of Sand, Silt & Clay.

2. Sub Soil: It lies below the top soil and supports moisture

3. Weathered Rock

4. Bed Rock: Consists of solid layer of unweathered Rock.

 

Types of Soil:

Soils are classified on the basis of colour, texture, fertility, mineral content, etc. Broadly, soil is classified into six types: -

1.   Alluvial Soil

2.   Black Soil

3.   Red Soil

4.   Laterite Soil

5.   Desert Soil

6.   Mountainous Soil

 

1. Alluvial Soil:

It is the most important and most fertile type of soil found in India covering about 40 per cent of the total land area.Soil is formed by the deposition of sediments brought down by the rivers.The alluvial soil is found mostly in the Northern Plains and Coastal Plains of India.The fine particles of sand, silt and clay are called alluvium. The alluvial soil can be divided into old alluvium, also called Bangar, and new alluvium, called Khadar.

2. Black Soil:

The black soil is also called the Black Cotton Soil. Cotton grows best in this soil.Black soil is formed from the weathering of the igneous rocks.The black soil is mostly found in the Deccan Trap, covering large areas of Maharashtra, Gujarat and western Madhya Pradesh. It is also found in some parts of Godavari and Krishna river valleys, covering parts of Karnataka, Andhra Pradesh and Tamil Nadu.

3. Red Soil:

Red soil is derived from the weathering of the igneous and metamorphic rocks.The red colour is due to the high percentage of iron contents.Red soil is found in the southern and eastern parts of the peninsular plateau.

4. Laterite Soil:

The laterite soil is widely spread in India and is mainly found on the summits of the Western Ghats, Eastern Ghats, Rajmahal Hills, Vindhyas, Satpuras and Malwa plateau.Due to intensive leaching, the laterite soil generally lacks fertility and is of low value for crop production. But when manured and timely irrigated, the soil is suitable for producing plantation crops like tea, coffee, rubber, coconut, etc.

Leaching is a process in which heavy rains wash away the fertile part of the soil.

5. Mountain Soil:

The mountain soil is generally found on the hill slopes covered with forests.This type of soil is found in the Himalayan region, the Western and Eastern Ghats and in some parts of the Peninsular India.This soil is rich in humus, but poor in potash, phosphorus and lime.This soil is especially suitable for producing plantation crops, such as tea, coffee.

6. Desert Soil:

The desert soil is found mostly in the arid and semi-arid regions, receiving less than 50 cm of annual rainfall.Such regions are mostly found in Rajasthan and the adjoining areas of Haryana and Punjab. The Rann of Kachchh in Gujarat is an extension of this region.The desert soil has sand (90 to 95 per cent) and clay (5 to 10 per cent).

 

 DEGRADATION OF SOIL

Soil erosion is the degradation of soil by human activities. Following are  the factors responsible for  the soil erosion:

1. Deforestation

2. Overgrazing

3. Construction

4. Overuse of Chemical Fertilizers

5. Pesticides

6. Natural Calamities (Flood, landslides, etc.)

 

CONSERVATION OF SOIL

Soil conservation means protection, preservation and proper utilization of the soil.Some methods of soil conservation are:

1. Mulching – Bare ground between plants is covered with a layer of organic matter like straw. It helps to retail soil moisture.

2. Contour Ploughing – Ploughing along contours can decrease the flow of water down the slopes.

3. Terrace Cultivation – Steps can be cut out on the slopes making terraces.

4. Strip Cropping – Strips of grass are grown between the crops. This breaks the force of wind.

5. Shelter Belts – Rows of trees are planted to create shelter. Thus, the speed of wind is reduced.

6. Rock Dam – Rocks are piled to slow the speed of wind.

7. Contour Barriers – Stones, grass and soil are used to make barriers. Trenches are made in front of the barriers to collect water.

8. Afforestation, Crop Rotation, Control over Deforestation and Overgrazing, etc.

 

 

WATER

THREE-FOURTH OF THE EART'S SURFACE IS COVERED WITH WATER.

 

Some Facts and Figures of Water:

1.   97 % of the total volume of water is covered by Seas and Oceans

2.   Out of 3% of the fresh water available, nearly 2% is in the form of "ICE" and is found in glaciers in Antarctica, Greenland, mountain regions, etc.

3. Only 1% of water is fit to use. It is found as underground water, surface water in rivers and lakes and also, water vapors' in the Atmosphere.

 

Water is available in three forms:

1.   Water vapor's

2.   Water in ocean, lakes & rivers

3.   Ice in the glaciers & ice caps

 

The fresh water is continuously being renewed and recharged through hydrological cycle.

Usage of Water:

1. Drinking                  2. Bathing                   3. Washing          4.  Cooking             5. Irrigation

6. Generating Electricity         7. Water used in Industries         8. Construction, etc.

 

PROBLEM OF WATER AVAILABILITY

• Water is available in abundance and is renewable. Then why we suffer from water scarcity?
• Water is not evenly divided around the world. Some places have lots and others have very little. Water supply is a big problem in some countries like, Africa, West Asia, South Asia, etc.
• According to Mr. Falkenmark (a Swedish Expert), Water Stress Indicator, a country or region is said to experience "water stress" when annual water supplies drop below 1,700 cubic metres per person per year. At levels between 1,700 and 1,000 cubic metres per person per year, periodic or limited water shortages can be expected. When water supplies drop below 1,000 cubic metres per person per year, the country faces "water scarcity".

 

CONSERVATION OF WATER

Some of the important ways to conserve water are: -

1.   Decrease of water pollution: Discharge of untreated sewage, agriculture chemicals & industrial effluents.

2.  Proper irrigation method:

      (a) Sprinklers can be used to irrigate very large area.

      (b) Drip irrigation can be used in dry regions, where evaporation is very high.

3.  Water Harvesting Method: This water can be used for cleaning, washing, gardening, etc.

4.  Water conservation in the home: -

• Check faucets and pipes for leaks.
• Check your toilets for leaks.
• Use your water meter to check for hidden water leaks.
• Install water-saving shower heads and low-flow faucet aerators.
• Put plastic bottles or float booster in your toilet tank.
• Insulate your water pipes.
• Take shorter showers.
• Turn off the water after you wet your toothbrush.
• Use your dishwasher and clothes washer for only full loads.
• When washing dishes by hand, don't leave the water running for rinsing.

 

NATURAL VEGETATION AND WILDLIFE

• Natural Vegetation and wildlife exist only in the narrow zone of contact between the Lithosphere, Hydrosphere and Atmosphere that is called "Biosphere".
• For the survival, all things are interlinked and interdependent on each other. This is known as "Ecosystem".

 

DISTRIBUTION OF NATURAL VEGETATION

Growth of natural vegetation depends on "Temperature and Moisture"

 

 

Vegetation of the world is grouped as: -

(a) Forests

(b) Grasslands

(c) Scrubs

 

 

(d) Tundra

(The tundra is a vast region of cold and ice occupying the northern reaches of Europe, Asia and North America. Plant life ekes by on little sunlight for most of the year. Temperatures are cool even in summer, and the growing season is brief, making scrub vegetation the dominant form. Scrub is a general term for any plant life that remains dwarfed and close to the ground for its own protection.)

 

 

Some important facts about the Vegetation:

• Forests grow, where temperature and rainfall are plenty to support a tree cover.
• Size of the trees decreases with the decrease in the amount of water.
• Forests are broadly classified as "Evergreen and Deciduous Forests" depending on when they shed their leaves.
• Regions with moderate rainfall – Short trees and grass can be found.
• Dry regions with less rainfall – Thorny bushes, shrubs and scrubs are grown. In these regions, plants have deep roots and leaves have thorny and waxy surface, to reduce water loss through transpiration.

 

 

CONSERVATION OF NATURAL VEGETATION AND WILDLIFE

• Wildlife conservation is closely related with the conservation of the natural vegetation.
• Deforestation, Overgrazing by animals, Forest fires, Hunting of animals, etc are some of the activities of the man, which has caused destruction of natural vegetation and wildlife.
• India has a rich variety of "Flora and Fauna".
• Species of plants and animals that do not exist now but existed in the past are called "Extinct Species". E.g.  Mountain Quail, Pink Headed Duck, etc.
• Species of some animals are on the verge of extinction as their population has decreased considerably. Such species are known as "Endangered". E.g. Tiger, Leopard, etc.

 

CONSERVATION OF FORESTS:

• National Forest Policy has been implemented.
• National Parks, Bioreserves, Botanical Gardens have been setup.
• Celebration of Van Mahotsav.
• Every National festival is followed by tree plantation ceremony.
• Large scale afforestation or planting of tress is undertaken.
• Controlling of deforestation and overgrazing.
• Practices like shifting agriculture have been stopped.

 

The government has taken some serious steps to protect the natural vegetation and wildlife. Some of them are given below: -

1.   Social Awareness Programmes.

2.   Wildlife Protection Act 1972.

3.   Special Projects: These have been launched to protect the endangered species. E.g. PROJECT TIGER - 29 Tiger reserves in India, PROJECT ELEPHANT – 14 Elephants reserves in India.

4.   Wildlife Sanctuaries: These are set up to prevent the extinction of animals. 510 wildlife centuries are there in India.

5.   National Parks: Areas where wild animals and natural vegetation are together preserved. There are 96 national parks in India.

6.   Bioreserves: These are large areas where vegetation, wildlife and environment are conserved to preserve the biological diversity. In total there are 14 bioreserves in India.

 

CHIPKO MOVEMENT

The modern Chipko movement started in the early 1970s in the Garhwal Himalayas of Uttarakhand,Then in Uttar Pradesh with growing awareness towards rapid deforestation.

The landmark event in this struggle took place on March 26, 1974, when a group of peasant women in Reni village, Hemwalghati, in Chamoli district, Uttarakhand, India, acted to prevent the cutting of trees and reclaim their traditional forest rights that were threatened by the contractor system of the state Forest Department. Their actions inspired hundreds of such actions at the grassroots level throughout the region.

 

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Objectives and Goals:

• The interior of the earth.
• The three different layer of the earth (i.e. Crust, Mantle and Core).
• Differences between rocks and minerals.
• The classification and characteristics of rocks (i.e. Igneous, Metamorphic and Sedimentary Rocks).
• The "Rock Cycle".
• The usefulness of rocks.

 

Some important points to remember:

• Lithosphere (outer part of earth's structure) was formed 5 billion years ago. 
• Geologists are the scientists who study the earth, its structure and substances. 
• Petrology is the science which studies rocks and its formations. 
• Fossils – remains of dead plants and animals are called fossils trapped in the layers of rocks. 
• Ore – a rock in which a particular mineral is found in large percentage is called an ore. 
• Plates – large blocks of earth's crust which are moving. 
• Magma – it is molten rock material inside the earth. 
• Rock cycle – rocks are continually being formed, destroyed and reformed due to changing weather conditions and forces of nature (eg. Wind, river, glaciers, earth movements, etc.)

 

The radius of Earth is 6371 kms.  Earth's interior is broadly divided into three layers: -

1. Crust – Forms only 0.5% of the total Earth's volume.

2. Mantle - Forms only 16% of the total Earth's volume.

3. Core - Forms only 83% of the total Earth's volume.

 

CRUST:

• Its is also called SIAL (Silica & Aluminum)
• The outermost and thinnest layer of Earth.
• It consists of lightest materials and its density is lowest.
• Average thickness varies from 5 to 8 kms under the ocean floors and 35 kms under the continental masses.
• Broken in large continental blocks called "Plates".
• Lower part of Crust (oceanic crust) is known as SIMA (Silica & Magnesium).

 

MANTLE:

• Layer located under the Crust is called "Mantle".
• Its thickness is about 2900 kms.
• This layer is in partially molted form.
• Lithosphere plates (Crust) floats on this layer.
• Layer is divided into two – Upper and Lower Mantle. The upper mantle is in solid form, whereas lower mantle is in semi-molten form.
• Average temperature: Upper Mantle – 870 degree Celsius and Lower Mantle – 2200 degree Celsius.
• This layer is made up of Iron, Magnesium and Silica.

 

CORE:

• The innermost layer, forming the metallic centre of the Earth.
• Core of the Earth is like a dense magnetic ball of minerals (Iron & Nickel). Hence, it is also called NIFE (NI – Nickel & Fe – Ferrous Magnesium i.e Iron).
• Temperature increases at the rate of 1degree Celsius for every 32 meters of depth.
• This layer is divided into two:

            (a) Outer Core: It is so hot that even metal also melts. Temperature is around 2200 degree Celsius.

            (b) Inner Core: Here the temperature is around 5000 degree Celsius.  Pressure is maximum in this layer.

 

MATERIAL OF THE EARTH'S CRUST

Earth's crust is composed of rocks and minerals. All solid materials of the earth's crust, whether hard or soft, that make up the earth's crust are called Rocks.

 

Characteristics of Rocks:

• They are made up of one or more minerals.They don't have a definite chemical composition.There are broadly 12 rocks forming minerals.
• Rocks form the solid mass of the earth's crust.
• The rock forming materials are known as "Minerals".
• Minerals are chemical substances found in nature. They have definite chemical composition and physical characteristics. Any variation in their proportion gives rise to a different mineral.
• Rocks containing minerals gives us metals like Copper, Iron, Gold, etc.

 

Rocks have different colours, mineral composition, hardness, etc. and according to their formation, rocks can be classified into three categories: -

1.  Igneous Rocks

2.  Sedimentary Rocks

3.  Metamorphic Rocks

 

1.  IGNEOUS ROCKS

The word 'Igneous' is derived from Latin word "Ignis" meaning "Fire".

• This is also called Primary rock. These are the first rocks to be formed. These are ancestors of all the rocks.
• Igneous rocks are the hardest rocks available and  it is formed by cooling and solidification of the Lava coming out from the interior of the Earth's interior. E.g. Granite, Basalt, etc.
• Solidification of rocks below the earth's surface is known "Intrusive rocks".
• The magma which reaches the earth's surface and gets solidified is known as "Extrusive Rocks".

Features of igneous rocks are: -

• These rocks do not form layers.
• They contain crystals of varying sizes.
• They do not contain fossils.

 

2.  SEDIMENTRY ROCKS

• The word 'Sedimentary' is derived from Latin word "Sedimentum" meaning "Settle Down".
• Particles that form a sedimentary rock by accumulating are called sediments.
• Before being deposited, sediment was formed by weathering and erosion in a source area, and then transported to the place of deposition by water, wind, ice, mass movement or glaciers which are called agents of denudation.

Features of igneous rocks are: -

• They are layered, called stratified rocks.
• They do not contains crystals.
• They contain fossils embedded in them.
• They are rich in coal and petroleum deposits.
• Examples of Sedimentary rocks are: - Sandstone, Clay, Limestone, etc.
• 70% of the total earth's surface is dominated with these rocks.

 

3.  METAMORPHIC ROCKS

• The word 'Metamorphic' is derived from Greek word "Metamorphose" meaning "Change of Form".
• When igneous or sedimentary rocks are subjected to great heat or pressure, the original character and appearance of the rock change into a new form. Thus, these rocks are formed by the alteration of other rocks. E.g. graphite, slate, Marble, etc.

Features of metamorphic rocks are: -

• They are hard in nature.
• Valuable minerals like gold & silver are found in these rocks.
• They do not contain fossils.
• Takes a long time to form.

 

ROCK CYCLE

Change into sedimentary rock or into metamorphic rock. Sedimentary rock can change into metamorphic rock or into igneous rock. Metamorphic rock can change into igneous or sedimentary rock. Hence, this cycle of change from one type of rock to another is called 'rock cycle'.

Rock Cycle: Rocks are continually being formed, destroyed and reformed due to changing weather conditions and forces of nature (eg. Wind, river, glaciers, earth movements, etc.)

             

 

ROCKS PROVIDE US:

• Different vegetations.
• Different types of minerals for industries.
• Different rock materials for construction purposes.
• Different chemicals for medicine and fertilizer industries.
• Source of fuels like coal and crude oil.Source of precious stones like, gold, silver, etc.

 

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Multiple Choice Questions:

Q1. A landmass bounded by sea on three sides is referred to as
(a) Coast                    (b) Peninsula
(c) Island                   (d) None of the above

Answer: (b) Peninsula

Q2. Mountain ranges in the eastern part of India forming its boundary with Myanmar are collectively called as
(a) Himachal              (b) Purvachal
(c) Uttarakhand          (d) None of the above

Answer: (b) Purvachal

Q3. The western coastal strip, south of Goa is referred to as
(a) Coromandel          (b) Kannad
(c) Konkan                 (d) Northern Circar

Answer: (b) Kannad

Q4. The highest peak in the Eastern Ghats is
(a) Anai Mudi             (b) Mahendragiri
(c) Kanchenjungaa     (d) Khasi

Answer: (b) Mahendragiri

 

Answer the following questions:

Q1. What are tectonic plates?
Answer: The crust of the earth is not in the form of a continuous plate rather in the form of broken pieces. These pieces of the earth's crust are called tectonic plates. Broadly, there are seven major plates: African Plate, Antarctic Plate, Eurasian Plate, Indo-Australian Plate, North American Plate, Pacific Plate and South American Plate.

 

Q2. Which continents of today were parts of the Gondwana land?
Answer: The Gondwana land included South America, Africa, Antarctica, Australia and India.

 

Q3. What is bhabar?
Answer: The rivers after descending from the mountains deposit pebbles in a narrow belt. The width of this belt is about 8 to 16 km and it lies parallel to the Shiwaliks. This region is known as bhabar. All the streams disappear in this region and the underground water level is deep in this region.

 

Q4. Name the three major divisions of the Himalayas from north to south.
Answer: Three major divisions of the Himalayas from north to south are:
(a) The Great or Inner Himalaya or Himadri
(b) The Lesser Himalaya or Himachal
(c) The Shiwaliks

 

Q5. Which plateau lies between the Aravali and the Vindhyan ranges?
Answer: The Central Highlands is the plateau which has Vindhya ranges in the South and Aravalis in the North West.

 

Q6. Name the island group of India having coral origin.
Answer: Lakshadweep is the island of India having coral origin.

 

Q7. Distinguish between:

(a) Converging and diverging tectonic plates
Answer:

 

(b) Bhangar and Khadar
Answer:

 

(c) Western Ghats and Eastern Ghats
Answer:

 

Q8. Describe how the Himalayas were formed.
Answer: The Indian Peninsula drifted towards the north and finally collided with the much larger Eurasian Plate. As a result of this collision, the sedimentary rocks which were accumulated in the geosynclines (known as Tethys) got folded and formed the mountain systems of the West Asia and Himalaya.

 

Q9. Which are the major physiographical divisions of India? Contrast the relief of the Himalayan region with that of the Peninsular Plateau.
Answer: The landmass of India can be divided into following major physiographic divisions:
(a) The Himalayan Mountains
(b) The Northern Plains
(c) The Peninsular Plateau
(d) The Indian Desert
(e) The Coastal Plains
(f) The Islands

The following compares and contrasts between the reliefs of the Himalayan region with that of the Peninsular plateau:

 

Q10. Give an account of the Northern Plains of India.
Answer: The northern plain of India is formed by three river systems, i.e. the Indus, the Ganga and the Brahmaputra; along with their tributaries. This plain is composed of alluvial soil which has been deposited over millions of years. The total area of the northern plain is about 7 lakh square kilometer. It is about 2400 km long. Width is about 240 to 320 km. Northern plains are most densely populated areas of the country. Here, we find alluvial soil, thus making the plain very fertile and agriculturally very productive. Because of the three river systems, i.e. the Indus, the Ganga and the Brahmaputra; along with their tributaries, availability of water is there in abundance through the year.

The northern plain is divided into three sections, i.e. the Punjab Plain, the Ganga Plain and the Brahmaputra Plain.

1. Punjab Plains: The Punjab plains form the western part of the northern plain. This is formed by the Indus and its tributaries; like Jhelum, Chenab, Ravi, Beas and Sutlej. A major portion of this plains is in Pakistan. Doabs are found in Punjab plains.

2. Ganga Plains: This plain extends between Ghaggar and Tista rivers. The northern states, Haryana, Delhi, UP, Bihar, part of Jharkhand and West Bengal in the east lie in the Ganga plains.

3. Brahmaputra Plains: This plain forms the eastern part of the northern plain and lies in Assam.

Based on the relief features; the northern plain can be divided into four regions, viz. Bhabar, Terai, Bhangar and Khadar.

1.Bhabar: After descending from the mountains, the rivers deposit pebbles in a narrow belt. The width of this belt is about 8 to 16 kms. It lies parallel to the Shiwaliks. Bhabhar is the gently-sloping coarse alluvial zone below the Siwalik Hills (outermost foothills of Himalayas) where streams disappear into permeable sediments. The underground water level is deep in this region.

2. Terai: The terai region lies towards south of the bhabar belt. In this region, the streams reappear and make a wet, swampy and marshy region. This region was full of forest and wildlife but after partition all this area was cleared and was converted into agricultural land for the settlement of the migrants.

3. Bhangar: Bhangar is the largest part of the northern plain and is composed of the oldest alluvial soil. They lie above the flood plains. They resemble terraces. The soil of this region is locally known as kankar and is composed of calcareous deposits.

4. Khadar: The floodplains formed by younger alluvium are called Khadar. The soil in this region is renewed every year and is highly fertile. This region is very suitable for intensive agricultural activities.

 

Q11. Write short notes on the following:

 

(a) The Indian Desert
Answer: The Indian desert lies towards the western margins of the Aravali Hills. This region gets scanty rainfall which is less than 150 mm in a year. Hence they climate is arid and vegetation is scanty. Luni is the only large river but some streams appear during rainy season. Crescent-shaped dunes (barchans) abound in this area.

 

(b) The Central Highlands
Answer: The Central Highlands lies to the north of the Narmada river. It covers the major portion of the Malwa plateau. The rivers in this region flow from southwest to northeast; which indicates the slope of this region. It is wider in the west and narrower in the east. Bundelkhand and Baghelkhand mark the eastward extension of this plateau. The plateau further extends eastwards into the Chhotanagpur plateau.

 

(c) The Island groups of India
Answer: The Lakshadweep Islands are in the Arabian Sea. Its area is 32 sq km. The administrative headquarters of Lakshadweep is at Kavaratti island. This group of islands is rich in terms of biodiversity.
The Andaman and Nicobar Islands are bigger in size and has more number of islands. This group of islands can be divided into two groups. The Andaman is in the north and the Nicobar is in the south. These islands too have rich biodiversity.

 

 

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If your mobile networks are affected today, Friday the 13th, blame it on solar flares. Three extremely powerful solar flares that the sun has emitted could send shockwaves through earth on Friday, scientists fear, news.com.au reports. The solar flares may disrupt the communication lines, causing blackouts. The three solar flares were all 'X-class' flares, which are almost 10,000 times as powerful as normal background flares from the sun. Solar flares, according to Live Science, are 'powerful bursts of radiation that are unleashed from the sun and speed out into space. They can sometimes produce waves of plasma and charged particles, called coronal mass ejections (CMEs). When aimed directly at Earth, CMEs can trigger geomagnetic storms and knock out communications and power grids on Earth.'