NCERT Revision Notes Chapter 7 Conservation of Plants and Animals Class 8 Science
CBSE NCERT Revision Notes1
Answer
• Deforestation
→ Causes of Deforestation
→ Consequences of Deforestation
• Biodiversity
• Protected areas
→ Wildlife Sanctuary
→ National Parks
• Biosphere Reserves
• Red Data Book
• Migration
• Recycling of Paper
• Reforestation
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Answer
Causes of Deforestation
→ Natural causes
→ Forest fire
→ Severe droughts
→ Man-made causes
→ Using land for agricultural purposes
→ Rapid urbanization
→ Procurement of wood for fuel and furniture
Consequences of Deforestation
→ Increase in the level of carbon dioxide in atmosphere, which leads to global warming
→ Lowering of ground water levels
→ Increase in pollution level and temperature
→ Decrease in fertility of soil and amount of rainfall
→ Increase in frequency of droughts and floods
→ Desertification- conversion of fertile lands into deserts.
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→ Biodiversity is the species richness of the biosphere. It is defined as the number and variety of life forms such as plants, animals and microorganisms in an area.
→ It supports all the essential living resources such as wild life, fisheries and forests.
→ Forests help in maintaining the delicate balance of nature.
→ Animals living in forests are called wild animals.
→ The plants found in a particular area are known as flora of that area.
→ The animals found in a particular area constitute fauna of that area.
→ Those species of plants and animals, which are found only in a particular area, are called endemic species.
→ Species is a group of organisms in population which are capable of interbreeding.
→ The animals, whose numbers are diminishing to a level that they might face extinction, are called endangered animals.
For example: tiger, lion, and elephants
→ Project tiger was launched by the government of India to protect endangered tigers in their natural habitat.
→ The flora and fauna of a particular habitat can be protected through special protected areas.
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A protected area is a clearly defined geographical space which is recognised and managed by government to achieve the long term conservation of nature, culture and preserve ecosystem.
Wildlife sanctuary
→ It is the place where wild animals are protected from hunting and are provided with suitable living conditions.
For example: Madhumalai wildlife sanctuary in Tamil Nadu, Chilika bird sanctuary in Orissa, etc.
National parks
→ These are the areas reserved for wildlife. They are maintained and preserved by the government for the public to visit.
For example: Ranthambore National Park in Rajasthan, Kanha National Park in Madhya Pradesh, etc.
→ Satpura National Park is the first reserve forest of India.
Biosphere Reserves
→ It is a large protected land for conservation of wild life, plant and animals resources, and the traditional life of the tribal groups living in the area.
For example: Pachmarhi Biosphere Reserve and Nilgiri Biosphere Reserve in India.
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→ It is the source book maintained by IUCN (International Union for Conservation of Nature and Natural resources).
→ It keeps a track record of various endangered species of plants and animals.
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→ It is the movement of birds and animals from their original habitat to other places at a particular time.
→ Migratory birds fly to distant areas every year during a particular time because of climatic changes their original habitat becomes very cold and inhospitable lack of food availability
→ Numerous migratory birds including ducks, geese, flamingos, and cranes fly to India every year.
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Answer
→ One ton of paper is made from about seventeen fully-grown trees.
→ Papers should be recycled and reused to conserve forest.
→ Each paper can be recycled three to seven times.
→ Recycling of paper saves trees, energy and water.
→ It prevents the release of harmful chemicals emitted during paper manufacturing in nature.
8
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→ Restoring of destroyed forests by planting new trees is called reforestation.
→ It helps in checking environmental degradation.