NIOS Class 10 Economics Chapter 23 Environment and Sustainable Development

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NIOS Class 10 Economics Chapter 23 Environment and Sustainable Development

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Also, you can read the NIOS book online in these sections Solutions by Expert Teachers as per National Institute of Open Schooling (NIOS) Book guidelines. These solutions are part of NIOS All Subject Solutions. Here we have given NIOS Class 10 Economics Chapter 23 Environment and Sustainable Development, NIOS Secondary Course Economics Solutions for All Chapters, You can practice these here.

Environment and Sustainable Development

Chapter: 23

MODULE 8: CONTEMPORARY ECONOMIC ISSUES

TEXTBOOK QUESTIONS (SOLVED)

INTEXT QUESTIONS 23.1

Q.1. What is meant by environment? 

Ans. The environment encompasses all living and nonliving things occurring naturally on earth or some region thereof.

Q.2. Name two main components of environment.

Ans. (i) Biotic element.

(ii) Abiotic elements.

Q.3. Name two renewable and two non-renewable resources. 

Ans. (a) Renewable Resources: (i) Forest and 

(ii) Water.

(b) Non-renewable Resources:

(i) Petroleum

(ii) Coal.

INTEXT QUESTIONS 23.2

Q.1. What is a pollutant?

Ans. A pollutant is waste material or substance which causes an undesirable change in natural resources or eco-system.

Q.2. Name any two sources of air pollution.

Ans. (i) Smoke from factories.

(ii) Exhaust of automobiles.

Q.3. Name two harmful effects of water pollution. 

Ans. (i) It causes diseases like cholera, typhoid etc.

(ii) It kills aquatic life.

Q.4. What is meant by noise pollution? 

Ans. Excessive and displeasing environ- mental noise that disrupts the activity or balance of human and animal life is a noise pollution.

INTEXT QUESTIONS 23.3

Q.1. What is meant by degradation of soil?

Ans. Soil degradation refers to undesirable change or disturbance in the quality of soil.

Q.2. What are two different kinds of degradation of environment? 

Ans. (i) Soil degradation.

(ii) Habitat degradation.

INTEXT QUESTIONS 23.4

Q.1. What do you mean by sustainable development?

Ans. Sustainable development is a pattern of resource use that meets human needs with preserving the environment so that these needs can be met not only in the present, but also for generations to come.

Q.2. Give one example of recycling of products for sustainable development of the environment.

Ans. We can reuse rain water by rain- water harvesting.

TERMINAL EXERCISE

Q.1. Distinguish between renewable and non-renewable resources. Give at least two examples of each.

Ans. Renewable resources are those resources which may be renewed. Examples of renewable resources include trees in the forests and fishes in the ocean.

On the other hand, non-renewable resources are those resources which can get exhausted or depleted over time as they are used up.

Examples of non-renewable resources include fossil-fuels and minerals like coal, natural gas etc.

Q.2. With the advancement of human civilization many environmental problems have cropped. Do you agree? Give reasons for your answer.

Ans. Yes, we agree that with the advancement of human civilization, many problems have cropped. The cropped problems include pollution of air, and water, degradation of natural resources, like soil and forests and the depletion of non-renewable resources like fossil-fuels and minerals.

Q.3. What is meant by air pollution? Name any three major sources of air pollution.

Ans. Air Pollution: Air pollution is the introduction of chemicals, particular matter or biological materials that cause harm or discomfort to human or other living organisms or damage to the natural environment or built environment into the atmosphere.

Three Major Sources of Air Pollution: There are many major sources of air pollution. Three of them are as follows: 

(i) Smoke from power plants, factories, furnaces etc.

(ii) Exhaust of vehicles and automobiles; like cars, buses, bikes, aeroplanes, ships etc. 

(iii) Fumes from paint, varnish, aerosol sprays and other solvents.

Harmful Effects of Water Pollution: Following are harmful effects of air pollution.

(i) Causes Water Borne Diseases: Pathogens present in water causes a number of water borne diseases such as cholera, typhoid etc. affecting human beings and animals like.

(ii) Affecting the Chemistry of Water: Water pollution affects the chemistry of water. The pollutants including toxic chemicals can alter the acidity, conductivity and temperature of water.

(iii) Disturbing the Natural Food Cycle: It also kills life that inhabits water- based ecosystem like fish, birds, plants etc. and hence disturbs the natural food-cycle, which causes instability in ecosystems.

Q.4. What is water pollution ? Mention major sources of water pollution. What are its harmful effects?

Ans. Water Pollution: Water pollution is the contamination of water bodies (like rivers, oceans and ground water) by pollutants discharged directly or indirectly into water- bodies without adequate treatment to remove harmful compounds.

Major Sources of Water Pollution: Major sources of water pollution include industrial chemicals and effluents, nutrients, waste water, sewage etc.

Q.5. What is noise pollution? Name its major sources.

Ans. Noise Pollution: Noise pollution is an excessive and displeasing environmental noise that disrupts the activity or balance of human or animal life.

Major Sources of Noise Pollution: Following are major sources of noise pollution: 

(i) Vehicular traffic; like cars, buses, aeroplanes, trains etc.

(ii) Industrial processes like stone- cutting, making steel plates, sewing, printing etc.

(iii) Construction work on roads, bridges, buildings etc.

(iv) Various noises from stereos, television etc. 

(v) Consumer products like air- conditioners, refrigerators etc.

Q.6. What is meant by soil-degradation? What are its major causes? Write two harmful effects of soil- degradation.

Ans. Soil-degradation: Soil, degradation refers to an undesirable or deleterious change or disturbance in the quality of land.

Major Causes of Soil-degradation: Following are major causes of soil degradation: 

(i) Excessive’ use of chemical fertilizers and pesticides.

(ii) Water logging caused by excessive irrigation. 

(iii) Over grazing of animals in fields which reduces plant cover and leaves the soil prone to erosion.

Two Harmful Effects of Degradation: 

(i) It leads to a loss of quality and productivity of the soil in an area.

(ii) It leads to a change in the species of plants and animals.

Q.7. What do you mean by habitat degradation? Mention its major causes. What are harmful effects of habitat degradation?

Ans. Habitat Degradation: Habitat degradation refers to the process in which habitats lose their normal functioning or quality to support native life due to human activities.

Major Causes of Habitat Degradation: Following are major causes of habitat degradation:

(i) Deforestation and wood extraction for the timber industry.

(ii) Conversion of forest land into agricultural land.

(iii) Urban expansion of natural habitats. 

(iv) Soil erosion and desertification which can lead to whole forest degenerating into deserts.

(v) Slashing or slash and burn agricultural methods where forests are burnt and crops grown using the ashes as a natural fertilizers.

Harmful Effects of Habitat Degradation: Following are harmful effects of habitat degradation:

(i) It has led to the loss of many valuable ecosystem services like the nitrogen, phosphorus, sulphur and carbon-cycles.

(ii) It leads to loss of biodiversity and species extinction which upsets the natural balance and may alter the ecosystem.

(iii) It vastly increases an area’s vulnerability to natural disasters like flood and drought, crop failure, spread of disease and water contamination.

(iv) It has also bad effect on agricultural land.

Q.8. What is meant by depletion of resources? Give two examples of resources whose reserves have been diminishing rapidly in the last 100-150 years.

Ans. Depletion of Resources: It refers to the exhaustion of raw materials in an area or region. Resource depletion is most commonly used in reference to farming, fishing and mining.

Two Examples of Resources whose reserves have been diminishing: The reserves of petroleum and natural gas have been diminishing rapidly for the last 100-150 years.

Q.9. What is meant by sustainable development? Suggest two ways by which we can contribute to sustainable development.

Ans. Sustainable Development: Sustainable development is a pattern of resource use that aims to meet human needs while preserving the environment so that their needs can be met not only in the present, but for generation to come. In other ways sustainable development is a kind of development that takes into account the needs of the economy and the environment without compromising either of the aspects.

Two ways to contribute to Sustainable Development: (i) Recycling i.e. using again or re-processing.

(ii) Consumption should be restrained to meeting our basic needs.

SOME IMPORTANT QUESTIONS FOR EXAMINATIONS

VERY SHORT ANSWER TYPE QUESTIONS

Q.1. What does the production of various goods and services require?

Ans. The production of various goods and services requires resources-both man-made and natural.

Q.2. State any two problems caused by the production of various goods and services.

Ans. (i) Pollution of air by fumes emitted by factories.

(ii) Pollution of our drinking water by sewage discharged into rivers.

Q.3. What are the impacts on resources when the demand for goods, services and resources are increasing? 

Ans. Resources are getting depleted and also being damaged irreparably.

Q.4. How do we destroy nature?

Ans. We destroy nature when we cut down forests, pollute the air and rivers and dig minerals from the earth.

Q.5. What does the environment encompass?

Ans. The environment encompasses all living and nonliving things occurring naturally on earth and some region thereof.

Q.6. Give any four examples of living elements.

Ans. (i) Birds.

(ii) Animals.

(iii) Plants. and 

(iv) Forests.

Q.7. Give any four examples of non- living elements.

Ans. (i) Air.

(ii) Water.

(iii) Rocks.

(iv) Sun.

Q.8. Differentiate between biotic elements and abiotic elements.

Ans. Biotic elements are living; like birds whereas abiotic elements are non-living like air.

Q.9. Give one point of significance of the environment.

Ans. The environment provides various resources to man-both renewable and non-renewable.

Q.10. What are renewable resources?

Ans. Renewable resources are those resources which are replenished easily over time and hence can be used without the possibility of the resource being depleted or exhausted.

Q.11. Give any two examples of renewable resources. 

Ans. (i) Trees in the forests.

(ii) Fishes in the ocean.

Q.12. What are non-renewable resources?

Ans. Non-renewable resources are those resources which can get exhausted or depleted over time as they are used up.

Q.13. Give any two examples of non- renewable resources.

Ans. (i) Coal.

(ii) Gas.

Q.14. Within what period, all our current energy sources would have been used up?

Ans. Within around 50-75 years.

Q.15. By whom are harmful wastes and by-products absorbed, cleaned and recycled?

Ans. Harmful wastes and by-products are absorbed, cleared and recycled by various natural processes.

Q.16. How does the environment sustain life?

Ans. The environment sustains life by providing bio-diversity.

Q.17. With the rapid use of resources, a lot of accompanying environment problems has cropped up. Name any three such problems.

Ans. (i) Pollution of air and water; 

(ii) Degradation of natural resources and

(iii) Depletion of non-renewable resources.

Q.18. What does the term “Pollution” refer to?

Ans. The term “Pollution” refers to an undesirable change in the quality of natural resources or natural ecosystem.

Q.19. Write down the ill-effect of e pollution. 

Ans. Pollution adversely affects the health of the living beings.

Q.20. By which of the living beings is pollution caused?

Ans. Pollution is caused by pollutant.

Q.21. What is a pollutant?

Ans. A pollutant is a wasteful material or substance which causes undesirable change in natural resources or ecosystems.

Q.22. Give any three examples of pollutants.

Ans. (i) Smoke.

(ii) Dust and poisonous gases in the atmosphere. 

(iii) Sewage from cities in water.

Q.23. What is air pollution?

Ans. Air pollution is the introduction of chemicals, particulate matter or biological materials that cause harm or discomfort to human or other living organisms or cause damage to the natural environment.

Q.24. What does polluted air include? 

Ans. Polluted air includes air sulphur oxide, nitrogenous gases, carbon monoxide, carbon dioxide, toxic chemicals and particular matter.

Q.25. How many people die each year from causes directly attributable to air pollution, according to the World Health Organisation?

Ans. According to the World Health Organisation, 2.4 million people die each year from causes directly attributable to air pollution.

Q.26. Out of air pollution and automobile accidents, which causes worldwide more deaths per year? 

Ans. Air Pollution.

Q.27. State any four diseases caused by air pollution.

Ans. (i) Wheezing.

(ii) Coughing.

(iii) Difficulty in breathing. and 

(iv) Aggravation of existing respiratory and cardiac conditions.

Q.28. Write down the bad effects of the diseases caused by air-pollution.

Ans. The bad effects of the diseases caused by air-pollution are: 

(i) Increased medication.

(ii) Increased doctor or emergency room visits.

(iii) More hospital admission and 

(iv) Permanent death.

Q.29. Classify the sources of air- pollution. 

Ans. (i) Artificial resources.

(ii) Natural resources. 

Q.30. What do you mean by artificial resources? 

Ans. Artificial resources mean those resources which are caused by human beings.

Q.31. State any two major artificial sources of air-pollution.

Ans. (i) Smokes from power plants, factories, furnaces etc.

(ii) Exhaust of vehicles and automobiles like cars, buses, bikes, aeroplanes, ships etc.

Q.32. Write any two major natural resources of air pollution.

Ans. (i) Dust from natural sources usually barren land.

(ii) Methane emitted by the digestion of food by animals.

Q.33. What is water pollution? 

Ans. Water pollution is the contamination of water bodies by pollutants discharged directly or indirectly into water bodies without adequate treatment to remove harmful compounds.

Q.34. What do you mean by water bodies?

Ans. Water bodies mean lakes, rivers, oceans and ground water.

Q.35. State the major sources of water pollution.

Ans. (i) Industrial chemicals and effluents.

(ii) Nutrients.

(iii) Waste water.

(iv) Sewage.

Q.36. State any three water-born diseases.

Ans. (i) Cholera.

(ii) typhoid.

(iii) diarrhoea.

Q.37. Write any two harmful effects of water pollution.

Ans. (i) It kills life that inhabits water.

(ii) It disturbs the natural food-cycle which causes instability in ecosystems.

Q.38. State any two major sources of water pollution.

Ans. (i) Oil spill and leakages from tankers and oil rigs. 

(ii) Industrial effluents released by factories into water bodies.

Q.39. What is noise pollution? 

Ans. Noise pollution is an excessive and displeasing environmental noise that disrupts the activity of balance of human or animal life.

Q.40. Give any two harmful effects of noise pollution.

Ans. (i) Noise pollution in the form of unwanted sound can damage physiological and psychological health.

(ii) It can cause annoyance and aggression.

Q.41. State any two major sources of noise pollution.

Ans. (i) Vehicular traffic like cars, buses aeroplanes, trains etc.

(ii) Construction work roads, bridges etc.

Q.42. Give two types of degradation. 

Ans. (i) Soil degradation. and

(ii) Habitat degradation.

Q.43. What does soil degradation refer to? 

Ans. Soil degradation refers to an undesirable or deleterious change or destruction in the quality of soil.

Q.44. Write down an adverse effect of soil degradation. 

Ans. Soil degradation leads to a loss of quality and productivity of the soil in an area.

Q.45. State any two causes of soil degradation.

Ans. (i) Excessive use of chemical fertilizers and pesticides.

(ii) Overgrazing by animals in fields.

Q.46. How much is worldwide damage caused by soil erosion per year? 

Ans. World wide damage from soil erosion is about $ 5400 billion (₹ 20 lakh crores) per year.

Q.47. What does habitat degradation refer to?

Ans. Habitat degradation refers to the process in which habitats lose their normal functioning or quality to support native life due to human activities.

Q.48. Give one adverse effect of habitat degradation.

Ans. Habitat degradation leads to reduced carrying capacity of that area i.e. the number of animals or plants of a particular species the area can support.

Q.49. State any two major causes of habitat degradation.

Ans. (i) Deforestation and wood extraction for the timber industry.

(ii) Conversion of forest land into agricultural land.

Q.50. What does the economic term “depletion of resources” refer to?

Ans. The economic term “depletion of resources” refers to the exhaustion of raw materials in an area or region.

Q.51. Write down any four resources which are very essential in our life. 

Ans. (i) Petroleum.

(ii) Natural Gas.

(iii) Coal.

(iv) Uranium.

Q.52. What is sustainable development?

Ans. Sustainable development is a pattern of resources use that aims to meet human needs while preserving the environment so that these needs can be met not only in the present, but also for generations to come.

Q.53. We can contribute to sustainable development in many ways. Give only one way.

Ans. Finding substitutes for non- renewable resources and using renewable resources judiciously.

Q.54. How can we use rain water?

Ans. We can reuse rain water by rainwater harvesting. 

Q.55. Make a list of items that can be recycled.

Ans. (i) Plastic.

(ii) Papers.

(iii) Polythene.

(iv) Glass.

Q.56. What do you mean by absorptive capacity of environment? 

Ans. Absorptive capacity of environment means the ability of environment to absorb degradation.

Q.57. Give two examples mis use of resources. 

Ans. (i) Use of wood as a household fuel. 

(ii) Use of rivers to absorb industrial effluents.

Q.58. Give two examples of over use of resources.

Ans. (i) Excessive exploitation of fossil fuels.

(ii) Excess of tree felling.

Q.59. What does “Biodiversity Loss” refer to?

Ans. “Biodiversity Loss” refers to the extinction of plants, animals and micro- organism due to deforestation.

Q.60. Who causes pollution?

Ans. A pollutant causes pollution.

Q.61. Write down some common pollutants.

Ans. Smoke, dust and poisonous gases in the atmosphere and industrial effluents and sewage from cities in water are common pollutants.

Q.62. Name the pollution which causes annoyance and aggression, hypertension, high stress levels, hearing loss, sleep disturbances etc.

Ans. Noise pollution.

Q.63. Which pollution causes diseases such as cholera, typhoid, diarrhea etc.

Ans. Water pollution.

Q.64. Name the pollution which causes difficulty in breathing, wheezing, coughing and aggravation of existing respiratory and cardiac condition. 

Ans. Air pollution.

Q.65. Write down the alternatives of petrol and

Ans. CNG and LPG are the alternatives of petrol and diesel.

Q.66. Out of vegetarian and non- vegetarian food, which food is eco-friendly.

Ans. Vegetarian food.

Q.67. Who absorbs the smoke from chimneys and exhaust pipes of vehicles, sewage from cities and towns and industrial effluents?

Ans. The environment.

Q.68. Which pollution is caused by smoke, particulate matter and carbon monoxide from wild fires?

Ans. Air Pollution.

Q.69. What does volcanic activity produce?

Ans. Volcanic activity produces sulphur, chlorine and ash particles. 

Q.70. If the current rate of deforestation continues, what percentage of the world tropical forests will be left by 2030? 

Ans. If the current rate of deforestation continues, there will only be 10% of the world’s tropical forests left by 2030.

Q.71. “Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs.” This definition emphasizes two important things. Name them.

Ans. (i) Natural resources are vital to every one of us-even to the unborn future generation. 

(ii) Sustainable development is a long- term concept.

Q.72. Give example of one exhausted resources.

Ans. Petroleum/Coal.

Q.73. Give one source of water pollution.

Ans. Discharge from sewage treatment plants and sewage pipes from cities and towns. 

Q.74. Name any two gases which cause air pollution.

Ans. (i) Nitrogen oxide. and 

(ii) Carbon monoxide.

Q.75. Write down the impact of advancement of human civilisation on human wants.

Ans. With the advancement of human civilisation, human wants have, expanded and diversified.

Q.76. Which noises from houses cause noise pollution?

Ans. Various noises of stereo, television and radio from houses cause noise pollution.

Q.77. Which consumer goods cause noise pollution?

Ans. Air-conditioners, refrigerators etc. cause noise pollution.

Q.78. Which elements cause degradation of land?

Ans. Water logging and soil erosion cause degradation of water.

SHORT TYPE QUESTIONS ANSWER 

Q.1. What is water pollution? State any three sources of water pollution.

Ans. Water pollution: Water pollution is the contamination of water bodies by pollutants discharged directly or indirectly into water bodies without adequate treatment to remove harmful compounds.

Three Sources of Water Pollution: (i) Discharge from sewage treatment plants and sewage pipes from cities and towns.

(ii) Industrial effluents released by factories into water bodies.

(iii) Release of heat or radioactive water by power plants.

Q.2. How are resources affected by increase in our necessities?

Ans. With the increase in wants, more goods and services are required to be produced. The production of more goods and services require more resources. As more goods are produced, more resources are used up resulting into the depletion of resources.

Q.3. Why is water pollution harmful for human beings?

Or

State any two harmful effects of water pollution.

Ans. Water pollution is harmful for human beings due to following reasons: 

(i) A number of diseases such as cholera, typhoid, diarrhoea are caused by water pollution.

(ii) Water pollution affects the chemistry of water. The pollutants including toxic chemicals can alter the acidity, conductivity and temperature of water.

(iii) It also kills life that inhabits water- based ecosystems like fish, birds, plants etc. and hence disturbs the natural food-cycle, which causes instability in water.

Q.4. Why is noise pollution harmful to human beings?

Ans. Noise pollution is harmful to human beings on account of following reasons:

(i) Noise pollution in the form of unwanted sound can damage physiological and psychological health.

(ii) It can cause annoyance and aggression, hypertension and high stress levels.

(iii) It can cause sleep disturbances.

(iv) It can cause hearing loss. 

(v) It may lead to rise in blood pressure.

Q.5. Why is air pollution harmful to human beings?

Ans. Air pollution is harmful to human beings due to following reasons: 

(i) Air pollution may cause difficulty in breathing.

(ii) It may cause aggravation of existing respiratory and cardiac condition.

(iii) It may cause wheezing and coughing.

Q.6. State any four sources of noise pollution.

Ans. Four Sources of Noise Pollution: There are many sources of noise pollution. Four of them have been stated below:

(i) Vehicular traffic; like cars, buses, aeroplanes, trains etc.

(ii) Construction of work on roads, bridge, buildings etc.

(iii) Various noises from house; like stereos, television etc.

(iv) Consumer products; like air-conditioners, refrigerators etc.

Q.7. Explain Recycling.

Ans. Recycling: Recycling is a process by which a used resource can be used many times. This process saves scarce natural We need wood-pulp for making paper. We get the wood-pulp from trees. Therefore, by recycling used paper, we can contribute to saving trees from being cut down. In the same way, we can use rainwater by rainwater harvesting.

Q.8. State which of the following are biotic elements and abiotic elements:

(i) Birds.

(ii) Animals.

(iii) Air.

(iv) Plants.

(v) Rocks.

(vi) Sun.

(vii) Water and 

(viii) Forests. 

Ans. (i) Biotic Elements:  

(i) Birds.

(ii) Animals.

(iii) Plants and 

(iv) Forests.

(ii) Abiotic Elements: 

(i) Air.

(ii) Water.

(iii) Rocks. and 

(iv) Sun.

Q.9. State which are renewable resources and which are non-renewable resources:

(i) Fossil-fuels.

(ii) Petroleum.

(iii) Trees in forests.

(iv) Natural gas.

(v) Coal. and 

(vi) Fish in the ocean.

Ans. (i) Renewable Resources: 

(i) Trees in the forests.

(ii) Fish in the ocean.

(ii) Non-Renewable Resources: 

(i) Fossil-fuels.

(ii) Petroleum

(iii) Natural gas and in Coal.

Q.10. Below are given the resources of air pollution, water pollution and noise pollution. Put them under various types of pollution.

(i) Chemicals like pesticides and fertilizers and dust from farming and other agricultural activities.

(ii) Volcanic activity which produces sulphur, chlorine and ash particles. 

(iii) Industrial effluents released by factories into water bodies.

(iv) Vehicular traffic like cars, buses, aeroplanes, trains etc.

(v) Discharge from sewage treatment plants and sewage pipes from cities and towns.

(vi) Exhaust of vehicles and automobiles like cars, buses, bikes, aeroplanes, ships etc.

(vii) Various noises from houses like stereos, television etc.

Ans. 

Q.11. Which type of pollution causes following diseases/problems:

(i) Difficulty in the breathing.

(ii) Cholera.

(iii) Wheezing.

(iv) Hearing loss.

(v) High stress level.

(vi) Diarrhoea.

(vii) Aggravation of existing respiratory and cardiac conditions.

(viii) Annoyance and aggression.

(ix) Sleep disturbance.

(x) Typhoid.

Ans. 

Q.12. Following are the examples of overuse and misuse of natural resources. State which is/are the example/s of overuse and which is/are the example/s of misuse of natural resource:

(i) Use of wood in the form of domestic fuel.

(ii) Excessive exploitation of fuels.

(iii) Excessive deforestation. 

(iv) Use of rivers for absorbing industrial resources.

Ans. 

Q.13. What is substitution? How does it help to check the environmental problems?

Ans. Substitution means the use of an alternative resource that is abundant instead of a natural resource that is scarce. Substitution saves scarce natural resource. Today there are various substitutes of petrol and diesel that can be used to run a vehicle. CNG, LPG and Ethanol replace scarce petrol and diesel whose stocks are limited.

Q.14. What is Global Warming?

Ans. Global Warming: It is a situation referring to a gradual, but consistent increase in global temperature due to environment pollution and deforestation. Due to emission of Green House Gases, the earth’s surface becoming increasingly warmer.