Get summaries, questions, answers, solutions, notes, extras, PDF and guide of Chapter 3 Destruction of Ecosystem, NBSE Class 9 Environmental Education textbook, which is part of the syllabus of students studying under Nagaland Board. These solutions, however, should only be treated as references and can be modified/changed.
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Summary
Land is a special resource that supports life. When people overuse or misuse natural resources, it harms the ecosystem. Sometimes, too much carbon dioxide or methane in the air can also cause harm. Natural disasters and human actions can destroy ecosystems. This destruction leads to problems like global warming, water shortages, and the loss of animal species.
Many things cause ecosystems to break down. Cutting down trees for farming or building cities reduces the number of plants and animals. Pollution in the air, water, and soil makes life hard for living things. Climate change caused by burning fuels changes weather patterns and affects animals. Overfishing, hunting too much, and cutting too many trees make it hard for nature to recover. Non-native plants or animals can hurt local species. Building cities takes away natural homes for animals.
The way people use land changes over time. Land can be used for forests, farming, or building houses. In some places, most land is used for farming, while in others, very little is. In areas with few people, there is enough land for animals to graze and for fun activities. In crowded places, even hills are turned into farms, and forests are cleared for houses. People have changed land for big farms, housing, factories, roads, schools, and shops.
Population growth changes how land is used. More people means more need for food, minerals, roads, and houses. Moving from villages to cities creates problems. Villages lose people, and cities become overcrowded. Factories and cities grow by taking over farmland and forests. More houses are built to fit everyone. Cars and trucks need roads, which take up space. Dams are built to produce energy, but they flood forests and farms. This forces people to move and changes the area.
Cutting forests for wood or farming harms the environment. Shifting cultivation, where farmers clear land and then leave it, is bad for animals and pollutes the air. Tourism and adventure activities create garbage and disturb wildlife. Mining for metals and stones damages the ground. War destroys land and pollutes the air, water, and soil. All these actions change how land is used and harm nature.
The 20th century saw a big rise in population. Migration from villages to cities affects both areas. Industrialization changes how land is used. Cities grow by taking over farmland and forests. Traffic jams and slums are common in big cities. Dams, deforestation, tourism, mining, and war all change how land is used. These changes affect the environment and the lives of animals and people.
Textbook solutions
Multiple Choice Questions (MCQs)
1. How much land is used for agriculture in Barbados?
(a) 70% (b) 77% (c) 75% (d) 80%
Answer: (b) 77%.
2. In 1950, the total population of the world was:
(a) 30 million (b) 40 million (c) 29 million (d) 35 million
Answer: (b) 40 million.
3. Who is the largest producer of hydropower in the world?
(a) India (b) Canada (c) England (d) America
Answer: (b) Canada.
4. Process of obtaining minerals from the earth’s crust is called:
(a) Logging (b) Dwelling (c) Mining (d) None of these
Answer: (c) Mining.
5. Rate of exhaustion of resources is …………..than the rate of replenishment for renewable resources.
(a) Slower (b) Faster (c) Equal (d) None of these
Answer: (b) Faster
Very Short Answer Questions
1. What do you understand by landuse?
Answer : Landuse refers to the land that is put to a particular use, such as forest, farming, construction, pasture, wasteland, etc. The pattern of landuse varies from area to area and country to country.
2. Which years experienced maximum increase in the population growth?
Answer : The 20th century witnessed a tremendous increase in population growth.
3. What are slums?
Answer : Slums are areas that develop in the big cities of developing countries, often characterized by poor living conditions and inadequate housing.
4. Name the common dwelling units in the cities?
Answer : The common dwelling units in the cities are houses or apartments that are constructed to accommodate the growing population, particularly due to the continuous entry of migrating populations into urban areas.
5. Which people indulge in shifting agriculture?
Answer : Shifting agriculture is practiced by people in regions such as North-East India, Central Africa, North-Eastern South America, and Asia. It is an ancient farming method widely used in these areas.
6. Name two types of mining?
Answer : The two types of mining are surface mining and underground mining.
Short Answer Questions
1. Why does rural urban migration take place in developing countries?
Answer : Rural to urban migration takes place in developing countries because people are shifting from rural areas due to low wages, uneconomic landholdings, poor facilities for education and health, and other factors that operate in rural areas, forcing people to move out. Additionally, as countries shift from an agricultural to an industrial base, streams of migration into urban areas occur, posing a lot of problems.
2. Why are industrial areas located at the outskirts of the city?
Answer : Industrial areas are located at the outskirts of the city because industries cause pollution, and therefore, they are allocated land away from the main urban areas to minimize their harmful effects on the population living in the city.
3. Give a brief description of urban landscape?
Answer : Urban landscape is characterized by major changes in the landscape due to urbanization. Most cities grow by annexing agricultural or forest land, leading to a tremendous change when agricultural landscapes convert into roads, buildings, and other structures. Skyscrapers can be observed in metropolitan cities, with roads and streets criss-crossing each other. Busy markets, movement of people, noises, and traffic jams are typical features of the city landscape.
4. How does transport change the urban landscape?
Answer : Transport changes the urban landscape by making people interact with remote areas and promoting trade, but it also leads to increasing dependence on vehicles. The problems associated with auto-vehicles include air pollution, traffic congestion, highway accidents, and the consumption of large amounts of energy sources. Traffic jams, noise pollution, and air pollution are common features of the urban landscape. Additionally, bridges and flyovers are increasingly being constructed in urban areas to accommodate growing traffic.
5. How does dams affect the landscape of the region?
Answer : Dams affect the landscape of the region by requiring huge construction activity to build the dam and canals. Large amounts of river water are stored in the form of a lake, which is used to generate power, and this changes the entire landscape of the area. A significant amount of forest land is submerged in the lake created by the dam, and many farmlands are also submerged. Additionally, a large number of people are displaced due to dam construction. A serious impact of hydropower is the occurrence of earthquakes, though they are not very frequent. In rare cases of dam failure, devastating floods may occur. Thus, the construction of dams causes destruction of the ecosystem and changes the land use pattern.
6. List two activities that require clear cutting of forests?
Answer : Two activities that require clear cutting of forests are logging and mining.
7. List two effects of clear cutting of forests?
Answer : Clear cutting of forests makes the soil naked, leading to excessive erosion, and results in the loss of habitat for animals, disturbing the ecosystem.
8. Give reasons for the encroachment on agricultural land?
Answer : Fertile agricultural land is annexed due to fast-expanding cities, and amusement parks are also being constructed on agricultural land. This changes the landscape of the region and disturbs the ecosystem. Additionally, the growing population demands more food, but agricultural land is decreasing every year, putting pressure on cultivable land to grow more food.
9. How does tourism and pilgrimage affect the landscape?
Answer : Tourism, pilgrimage, recreation, and adventure activities affect the landscape in several ways:
(i) The clean environment starts becoming unclean because a large number of tourists need water, housing, sewage facilities, etc.
(ii) Nowadays, even National Parks and Wildlife Sanctuaries have become tourist spots, where rare species may become victims of human intervention.
(iii) Pilgrimage centers are often littered with garbage, which changes the landscape of the region.
(iv) Several recreational parks in big cities attract thousands of visitors daily, who litter the beautiful parks. Adventurous water games are more susceptible to spreading waterborne diseases.
(v) In mountains, adventurous sports attract many people, contributing to changes in the landscape and environmental degradation.
10. What is the effect of bomb explosion on the landscape?
Answer : When bombs explode, all the buildings are razed to the ground, and the landscape changes in seconds. Besides killing many people, even traditional weapons are very destructive, which are capable of destroying the environment with noise, air, soil, and water pollution.
Long Answer Questions
1. Rapidly growing population compels change in landuse pattern. Discuss.
Answer : Rural to urban migration affects rural as well as urban areas. The rate of exhaustion of resources is faster than the rate of replenishment for renewable resources. Increasing population growth creates unprecedented demand for the resources. In order to meet the requirements of the growing population, the landuse is changed for more food, more minerals, more roads, more cities, and more houses. The growth of the human population gives birth to conditions like urbanization and industrialization. Due to industrialization, depletion of resources and erosion of land surface also arise. Fertile agricultural land is sacrificed for city growth, affecting agricultural production, which is enhanced by the application of chemical fertilizers, further deteriorating the ecosystem.
Change in landuse pattern is to a great extent associated with industrialization. Most cities grow by annexing agricultural or forest land. Slums develop in the big cities of developing countries. Traffic jams are a common feature of the urban landscape. Dams, deforestation, and shifting cultivation affect landuse patterns. Tourism, mining, and war also contribute to the changing landuse pattern.
2. How does rural-urban migration affect the rural and urban areas?
Answer : Rural-urban migration affects both rural and urban areas in the following ways:
In rural areas:
i. Villages become under-populated as people move to urban areas due to factors like low wages, uneconomic landholdings, and poor facilities for education and health.
ii. Rural resources remain underutilized.
In urban areas:
i. Cities become overpopulated, leading to acute pressure on urban resources.
ii. The land use pattern is altered to meet the requirements of the growing urban population.
iii. Urbanization leads to major changes in the landscape, such as agricultural or forest land being converted into roads, buildings, and other infrastructure.
iv. Skyscrapers, busy markets, movement of people, noise, and traffic congestion become typical features of the urban landscape.
v. Migration affects not only the ecosystem of rural areas but also of urban areas.
3. Describe the role played by the industries in affecting the landuse.
Answer : Industries play a significant role in affecting land use as they require land to build. Huge amounts of forests have been cut down for industrialization. As more industries are set up, there is an increased need for human resources or manpower. The adverse effects of industrialization include the requirement of more land to build houses or apartments for the settlement of people. Industries also cause pollution and are therefore allocated land in the outskirts of cities, referred to as industrial areas. This area is created either by sacrificing fertile agricultural land or forests. Lush green fields and forests are converted into large structures with smoke-releasing smokestacks. Thus, the change in land use patterns is significantly associated with industrialization.
4. What is urbanization? How does it change the landuse pattern?
Answer : Urbanization is the process of growing urban population and is related to industrialization. It leads to major changes in the landscape, such as cities growing by annexing agricultural or forest land. This results in a tremendous change when agricultural landscapes convert into roads, buildings, etc. Urbanization causes changes in landuse patterns by increasing the demand for housing, infrastructure, and other urban facilities, which often come at the expense of fertile agricultural land and forests.
5. What type of dwelling units develop in the cities? Give reasons.
Answer : In cities, common dwelling units include houses, apartments, and slums. Houses or apartments are constructed to accommodate the growing population, particularly due to the continuous entry of migrating populations into urban areas. This creates pressure on land, leading to changes in land use patterns. Slums, on the other hand, develop in the big cities of developing countries, often as a result of rural-to-urban migration, where people move to cities in search of better opportunities but end up living in informal settlements due to a lack of affordable housing.
6. Give a detailed account of the causes of deforestation?
Answer : Deforestation takes place due to several factors, which include:
i. Increasing population growth has led to the fast exploitation of forests as man tries to get too much in little time from forests, exerting immense pressure on them.
ii. Growing demand for wood, which is a major building material, has resulted in large-scale cutting of trees.
iii. More area is required to put under cultivation to meet the food requirements of the growing population, leading to the sacrifice of forest cover.
iv. The clear-cutting technique of felling trees, where all the trees of an area are removed abruptly, is very harmful as it makes the soil naked and leads to excessive erosion.
v. Habitat for animals is lost due to deforestation, disturbing the ecosystem severely.
7. How does mining affect the landuse pattern?
Answer : Mining affects the landuse pattern as it involves extracting useful minerals from the surface of the earth, including the seas. The increasing demand for power exhausts reserves of coal, petroleum, etc., and rapid urbanization requires large amounts of construction materials like limestone, marble, slate, and granite. All these minerals are extracted from the surface or beneath the surface of the earth. The methods of obtaining minerals damage the landscape severely. In many cases, several gases are also released into the atmosphere, and a lot of coal dust spreads in areas where coal mining is practiced, which can damage the landscape and ecosystem severely.
8. War besides killing several people also affects the landuse. Explain.
Answer : War impacts land use in various ways. International tensions between neighboring countries lead to a warlike situation, where defense forces occupy a significant amount of area along international borders. During such situations, forests are often cleared for the easy movement of troops and war materials. When war actually breaks out, fields are frequently damaged by vehicles like tanks rolling on the ground. Additionally, bunkers are constructed by digging into the land. Explosions caused by bombs destroy buildings and drastically alter the landscape within seconds. Even traditional weapons contribute to environmental destruction through noise, air, soil, and water pollution.
Extras
Additional questions and answers
1. Which two greenhouse gases causing ecosystem degradation?
Answer: The two greenhouse gases causing ecosystem degradation are carbon dioxide and methane.
26. Outline three strategies that might help restore or protect ecosystems.
Answer: The following strategies might help restore or protect ecosystems:
- Protecting natural habitats.
- Reducing pollution.
- Promoting sustainable practices.
Additional MCQs
1. What is the main cause of ecosystem destruction?
A. Overexploitation
B. Natural calamities
C. Climate change
D. Invasive species
Answer: A. Overexploitation
62. Factors such as dams, deforestation, and shifting cultivation affect?
A. Landuse pattern
B. Population growth
C. Urban planning
D. Mining activity
Answer: A. Landuse pattern
Ron’e Dutta is a journalist, teacher, aspiring novelist, and blogger who manages Online Free Notes. An avid reader of Victorian literature, his favourite book is Wuthering Heights by Emily Brontë. He dreams of travelling the world. You can connect with him on social media. He does personal writing on ronism.
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