CBSE Class 10 Science HOTs Management of Natural Resources

Question. Expand the abbreviation GAP 

Very Short Answer Type Questions

Question. Name two important natural resources.
Answer : Forest, Water, Wildlife.

Question. Define biodiversity.
Answer : The number of species found in an area is called biodiversity.

Question. Why fossil fuels should be used judiciously?
Answer : It is because these resources are limited, non-renewable and polluting.

Question. Name the place where “Chipko Andolan” organised.
Answer :  Reni Village in Garhwal.

Question. Name the main constituents of coal and petroleum.
Answer : Carbon, nitrogen, hydrogen, sulphur.

Question. State two disadvantages of constructing dam.
Answer : It can cause earthquakes, loss of habitat, submerging of plants releases methane gas that causes green house effect.

Question. Name two dam projects which are facing criticism.
Answer : Tehri dam on river Ganga and Sardar Sarovar dam on river Narmada.

Short Answer Type Questions

Question. Why do we need to use our resources carefully?
Answer : It is because these resources are limited and the human population is increasing at very fast rate, the demand for these resources is increasing. For long term usage and to preserve them we need to use our resources carefully. 

Question. Why are forests called as biodiversity hot spots?
Answer : Biodiversity hot-spot means a place where large number of species are found.
The range of different life forms i.e., bacteria, fungi, ferns, flowering plants, variety of animals likes, insects, birds, reptiles, aves, mammals etc are all found in the forest.

Question. Prejudice against the traditional use of forest areas has no basis. Comment.
Answer : It can be explained with one example—The great Himalayan Park contain alpine meadows which were grazed by sheep in summer. Nomadic shepherds drove their flock up from the valley every summer. When the National Park was formed this
practice was banned. Because of no grazing, the grass first grew very tall and then fell over on the ground preventing fresh growth. Hence the traditional use was helpful for the forest maintenance.

Question. Why is it necessary to conserve forest and wildlife?
Answer : To preserve forest, maintain balance in the eco-system, prevent floods, droughts.

Question. Name the products of combustion of coal and petroleum. How do they effect our environment?
Answer : CO₂, H₂O, oxides of sulphur and nitrogen are released from the combustion of coal and petroleum.
Effect on environment:
(i) CO₂ — Green house effect, global warming.
(ii) Oxides of sulphur and nitrogen causes acid rain.

Question. Give an example of people’s participation in the management of forests.
Answer : Saving of sal forest of Arabari in Midnapore District.
Chipko Movement to protect the trees from cutting down in Reni village Garhwal.

Question. Which is better—recycle or reuse? Give example.
Answer : Reuse is better because recycling needs extra energy.
E.g., the glass containers in which we get jam, pickles etc., can be reused at home to keep kitchen stuff but if it goes for recycling then lot of energy and money is spent on recycling it and getting a new bottle.

Question. Give three changes you will make to stop or lower the use of coal and petroleum.
Answer : (i) Switch off lights when not required, and use CFL bulbs.
(ii) Not to use petrol fuel vehicles instead opt for CNG.
(iii) Use cycle or walk to go short distances.

Question. Inspite of plenty rainfall in monsoon in some areas of India, there is failure to sustain water availability. Give reasons.
Answer : (i) Loss of forest cover prevents rainwater from seeping down the ground.
(ii) Underground water is not recharged.

Question. Give three main uses of fossil fuels.
Answer : (a) Fossil fuels are used for generating electricity i.e., Coal is used in thermal power plants on large scale to produce electricity.
(b) Coal and petroleum is also used in industries to prepare goods from raw-materials.
(c) Petroleum is used for transportation. In vehicles petrol or diesel is used.

Long Answer Type Questions

Question. What is sustainable development? Explain it with respect to forest, wildlife and water resources.
Answer : The proper management of natural resources using it wisely and judiciously so that it is available for the coming generations also. All these resources are maintained.
The population is increasing, demand for these resources is also increasing but they are limited in nature.
The management would prevent the exploitation of these resources and keep them available for future generations.
Forest—Many industries like timber, wood bidi, tendu leaves etc are dependent on the trees in the forest. They keep cutting the trees for use.
This need to be managed properly and checked that new plantation of trees take place, animals are not harmed and are preserved.
Wildlife—All animals in the forest are disturbed due to the intervention of people into the forest. They are also killed for trade of skin, fur, tusk horn etc. If the animals in the forest are not managed and taken care of then they will be extinct which will disturb the ecological balance of the earth.
Water Resources—The main water resources are rivers, lake, ponds, underground water. The sources of water are getting polluted and the underground water is also discharged, used and the level of water is declining. Hence the recharge of water under the ground by rain water harvesting is necessary.

Question. Dams are constructed on the river for multipurpose use give its advantages and disadvantages.
Answer : Advantages of dams:
(i) The water stored in the dams is used for irrigation by constructing canals which carry water to the fields.
The Indira Gandhi Canal carries water from Bhakra dam Punjab to villages in Rajasthan desert where it has brought greenery and added life to the soil.
(ii) The water in dams is continuously available for the people in the vicinity to make use of it after purification.
(iii) The water of dam is also used in producing electricity. The water in dam that falls from a certain height gains kinetic energy and rotates turbines to generate electricity. Hence this way it makes hydroelectricity.
Disadvantages of dams:
(i) Social Problems: Due to dam’s construction large number of human settlements are submerged in water, many people become homeless. Govt. must provide adequate compensation for the rehabilitation of these people which is not being done.
(ii) Ecological problems: Lot of deforestration takes place for the construction of dams, which leads to loss of biodiversity. Many plants get submerged under water and on decomposition this releases methane gas; that is the greenhouse gas; causing global warming.
(iii) Economic problems: For the construction of dams large funds are required, Govt. invests lot of money in its construction and the benefits or the output is not equivalent.

Value Based Questions

Question. Arjun’s father dropped him to school every day in his car but when he learnt about the pollution he started using school transport thereafter.
(a) Give two disadvantages of using fossil fuel.
(b) Why should we use these resources wisely and judiciously?
(c) What value of Arjun is reflected?
Answer : (a) Two disadvantages of using fossil fuels are: It causes pollution and it is expensive
resource which cannot be replenished.
(b) These resources are limited and take long time in formation.
(c) Arjun is showing responsible behaviour and self-discipline.

Question. What does the high level of total coliform count in river Ganga indicates?

Answer :. It indicates that water is contaminated by disease causing micro-organisms.

Question. What are “biodiversity hot spots”? What is the measure of the biodiversity?

Answer : Forests are “biodiversity hot spots”. One measure of the biodiversity of an area is the number of species found here.

Question. Which programme was started to replenish forests?

Answer : Silviculturea

Question. Why scarcity of water is there in our country inspite of nature’s monsoon bounty?

Answer : It has taken place due to the following reasons:

(a) Failure to sustain water availability underground which has resulted largely from the loss of vegetation cover.

(b) Diversion for high water demanding crops. 

(c) Pollution from industrial effluents and urban wastes.

Question. What is the effect of continuous depletion of ground water along coastal region?

Answer : The effect of continuous depletion of ground water along coastal region will lead to movement of saline sea water into freshwater wells then spoiling their quality.

Question. Why is dependence of man on nature greater than that of any other organism?

Answer : Man’s dependence on the environment is greater than that of other organisms because man:

(a) Develops curiosity for more comforts and security. 

(b) Consumes large amount of material and energy.

(c) Develops a new kind of socio-economic environment which consists of things developed by man through his tools and techniques.

Question. In addition to low rainfall, what are the other reasons for non-availability of water in arid and semi-arid zones of our country?

Answer : (a) Flowing of rain water and lack of management to harvest it.

(b) Ground water is pumped out for high water demanding crops.

(c) Water becomes unsafe and unusable due to mixing of urban wastes and effluents from the industries.

Question. Why is mining a big source of pollution?

Answer : Mining causes pollution because large amount of slag is discarded for every tonne of metal extracted.

Question. Write two points to be kept in mind while storing water in tanks.

Answer : Storage tank should not be located close to the source of contamination and should be accessible for cleaning.

Question. Write any two alternatives to dams.

Answer : Adopting water harvesting techniques and reducing the scale of floods through better catchment management.

Question. Why do you think there should be equitable distribution of resources?

Answer : We think that there should be equitable distribution of resources because not only a handful of rich and powerful people, but all the people may get benefit from the development of these resources.

Question. Which canal has brought greenery to considerable areas of Rajasthan?

Answer : Indira Gandhi Canal.

Question. What were the two main problems as a result of Tawa Irrigation Project?

Answer : Water logging and increasing salinity

Question. Write the advantages of giving the control of water management to the residents of the area?

Answer : Water harvesting techniques are highly locality specific and the benefits are localised. Thus, giving people the control over their local water resources ensures that mismanagement and overexploitation of these resources is reduced.

Question. State benefits of water harvesting.

Answer : a. Provides self-sufficiency to water supply

b. Conserves valuable ground water

c. Reduces cost for pumping ground water. 

d. Reduces local flooding and drainage problems

Question. How did Chipko Andolan ultimately benefit the local population? Give any three benefits?

Answer : a. The locals benefitted from forest produces

b. The wild life and nature were conserved 

c. The quality of air and soil was preserved

Question. Quote three instances where human intervention saved the forests from destruction.

Answer : a. Contribution of Bishnoi movement

b. Building national parks 

c. Encouraging wildlife sanctuaries

Question. Why are environmentalists insisting upon sustainable natural resource management? Give any four reasons.

Answer : a. Non-renewable resources are limited, we should use them judiciously

b. We should encourage the use of renewable resources

c. We should preserve the environment for future generation 

d. The benefits of the controlled exploitation should go to local people.

Question. Which of the following is the age old concept of water harvesting system in Madhya Pradesh ?
(a) Bundhis
(b) Ponds
(c) Bandharas
(d) Nadis

Answer : A

Question. Ground water will not be depleted due to 
(a) afforestation
(b) thermal power plants
(c) loss of forest, and decreased rainfall
(d) cropping of high water demanding crops

Answer : A

Question. Which of the following are to be managed for sustainable development?
(a) Industries
(b) Forests
(c) Crops
(d) Resources

Answer : D

Question. Match the following traditionalwater harvesting with their respective region. 66
(a) 1. (a), 2. (c), 3. (d), 4. (b)
(b) 1. (c), 2. (a), 3. (d), 4. (b)
(c) 1. (d), 2. (a), 3. (b), 4. (c)
(d) 1. (c), 2. (b), 3. (a), 4. (b)

Answer: B

Question. Which of the following is best method from environment point of view?
(a) Reduce
(b) Recycle
(c) Reuse
(d) All of these

Answer: D

Question. Kulhs is to Himachal Pradesh as bandharas is to ______.
(a) Rajasthan
(b) Tamil Nadu
(c) Kerala
(d) Maharashtra

Answer: D

Question. Which of the following sets has all the industries that depend on forests?
(a) Rubber, plastic and glass
(b) Textile, ceramic and marble
(c) Rubber, textile and glass
(d) Paper, lac and sports equipment

Answer: D

Question. Floods can be prevented by:
(a) Afforestation
(b) Removing top soil
(c) Deforestation
(d) Agriculture

Answer: A

Question. Select the incorrect statement. 
(a) Economic development is linked to environmental conservation.
(b) Sustainable development encourages development for current generation and conservation of resources for future generations.
(c) Sustainable development does not consider the view points of stakeholders.
(d) Sustainable development is a long planned and persistent development.

Answer: C

Question. Khejri trees in Khejrali village were saved by a group of
(a) men
(b) women
(c) children
(d) old

Answer: B

Question. Which of the following statements is incorrect?
(a) The five R’s of resource management are for fossil fuels only.
(b) Sustainable development also involves the safe disposal of wastes.
(c) Equitable sharing is an important feature of sustainable development.
(d) Earth has an unlimited supply of all-natural resources.

Answer: A

Question. Water harvesting is a method which?
(a) Increases ground water level.
(b) Not practiced in modern days.
(c) Has no relation with ground water.
(d) Decreases ground water level.

Answer: A

Question. The major ill effect of monoculture practice in forests is on the: 
(a) biodiversity which faces large destruction.
(b) local people whose basic needs can no longer be met from such forests.
(c) industries.
(d) forest department.

Answer: A

Question. Which gas is formed, when fossil fuels are burnt in insufficient air (oxygen)?
(a) Carbon dioxide
(b) Carbon monoxide
(c) Both CO₂ and CO
(d) Neither CO₂ nor CO

Answer : B

Question. From the list given below pick the item that is not a natural resource 
(a) Soil
(b) Water
(c) Electricity
(d) Air

Answer : C

Question. When we destroy a forest, we destroy
(a) the trees
(b) population of wildlife
(c) the environment
(d) food and shelter of wild animals

Answer : C

Question. Which environmental problem is associated with the construction of high rise dams?
(a) A large number of human settlements are submerged in the water.
(b) It contributes to deforestation and loss of biodiversity.
(c) It involves the spending of huge amounts of money.
(d) All the above.

Answer : D

Question. In our country, vast tracts of forests are cleared and a single species of plant is cultivated. This practice promotes 
(a) biodiversity in the area
(b) monoculture in the area
(c) growth of natural forest
(d) preserves the natural ecosystem in the area

Answer : B

Question. Which of the following community in Rajasthan has a religious tenet of conservation of forest and wildlife ?
(a) Agarwal
(b) Jaishwal
(c) Bishnoi
(d) Jain

Answer : C

Question. Surangams are the age-old concept of water harvesting in
(a) Karnataka
(b) Kerela
(c) Tamil Nadu
(d) Andhra Pradesh

Answer : B

Question. What is the purpose of rain-water harvesting?
(a) To hold rain water on the surface of the earth.
(b) To recharge ground water.
(c) To use water for the irrigation of crops.
(d) To rear fish

Answer : B

Question. Which of the following is not an use of forest ?
(a) Controls floods.
(b) Used to make paper.
(c) Causes soil erosion.
(d) Resin, gum and drugs are obtained.

Answer : C

Question. The Indira Gandhi Canal has brought greenery to considerable areas of
(a) Gujarat
(b) Rajasthan
(c) Bihar
(d) Madhya Pradesh

Answer : B

Question. Which one of the following is an example of renewable resource ?
(a) Coal
(b) Petroleum
(c) Wildlife
(d) Natural gas

Answer : C

Question. Among the statements given below select the ones that correctly describe the concept of sustainable development 
(i) Planned growth with minimum damage to the environment
(ii) Growth irrespective of the extent of damage caused to the environment
(iii) Stopping all developmental work to conserve the environment
(iv) Growth that is acceptable to all the stakeholders
(a) (i) and (iv)
(b) (ii) and (iii)
(c) (ii) and (iv)
(d) (iii) only

Answer : A

Question. What are the three R’s to save the environment?
(a) Reduce, Recycle, Reuse
(b) Replenish, Reduce, Reuse
(c) Reconstruct, Recycle, Reduce
(d) Reduce, Recycle, Remove

Answer : A

True and False :

Question. Monoculture forestry is more suitable for industries but it is not good for the environment. 
Answer: True

Question. Control of local people over their own water resources may cause mismanagement and over-exploitation of these resources. 
Answer: False

Question. The river water is said to be polluted with acidic wastes when the pH of river water above 7. 
Answer: False

Question. Soil and water are non-renewable natural resources.
Answer: False

Question. Revival of ancient systems of water harvesting is better than big dams. 
Answer: True

Very Short type Questions :

Question. Define the term ‘Conservation of environment’.
Answer: Conservation of environment means ‘to keep safe the environment as it is’, i.e. the sensible use of the earth’s natural resources in order to avoid excessive degradation and betterment of the environment.

Question. Name two industries based on forest produce. 
Answer: Timber industry, paper manufacturing industry, lac industry and sports equipment industry. 

Question. State the main purpose of rain-water harvesting.
Answer: It is done to recharge the ground water by percolating water under the soil.

Question. Name a clean fuel other than LPG and Natural gas.
Answer: CNG.

Question. Name any two forest products, each of which is the basis for some industry. 
Answer: Explanation:
(i) Pine wood for matchbox industry
(ii) Bamboo for paper industry

Question. What do you call the resources, viz, coal, petroleum, water, wildlife, etc.?
Answer: Natural resources.

Question. Which fossil fuel is conserved when we use bicycle for covering short distances instead of vehicle?
Answer: Petroleum.

Question. How does increasing demand for energy adversely affect our environment?
Answer: To meet the increased demand for energy, more and more natural resources are exploited. Pollutants are emitted during exploitation and use of natural resources which affect our environment.

Question. You must have heard the word ‘water harvesting.’ What does it mean?
Answer: It means capturing rain water or run off in a local area.

Question. What are the obj ectives of Namami Gange Programme?
Answer: Namami Gange Programme was launched to accomplish twin objectives of effective abatement of pollution and rejuvenation of river Ganga.

Short Answer Type Questions :

Question. What is “repurpose”?
Answer: Repurpose is the recovery of waste without any preprocessing.
For example, waste oils that cannot be refined for reuse in vehicles can be burnt for energy recovery.
Recovering the energy from waste oil reduces our dependence on coal and imported oil.

Question. List three advantages each of:
(i) Exploiting resources with short-term aims.
(ii) Using a long-term perspective in managing our natural resources.
Answer:
(i)
(a) Short-term exploitation will meet the demand of present generation.
(b) There will be no shortage of resources.
(c) Larger aspect regarding the details of a reserve can be studied also.
(ii)
(a) Long-term management of natural resources would meet the demand of present and future generation.
(b) No harmful impact on the environment.
(c) Equitable distribution of resources amongst the rich and poor.

Question. Major rivers in India have high bacterial contamination, Yamuna and Ganga top the list of most polluted rivers. 

The graph above shows the Distribution of total coliform bacteria in river water and biofilms. E1 to E5.
(i) Which among the following is the most polluted?
(ii) State the reason for bacterial contamination in water body.
Answer:
(i) E5 is most polluted river body.
(ii) Bacterial contamination in water is indicated by the presence of coliform bacteria. Bacterial contamination in water is mostly through untreated sewage and cause waterborne diseases.

Question. How industry is affecting the forest?
(ii) State the main aim of the management of forests and wild life.
Answer:
(i) Industries depend on forests as a resource provider and exploit all the resources to the maximum without any scope of conservation. The various industries which are based on
forest produce are; timber industry, paper manufacturing industry, 'lac' industry and sports equipment industry.
Forests are also treated as hunting and fishing sites and a source of raw materials for many industries. The deforestation caused due to the development projects and industrialisation is a serious issue.
(ii) The main aim of the management of forests and wild life is to conserve the biodiversity which we have inherited.

Question. State the significance of Chipko movement.
Answer: Chipko movement awakened people to the importance of maintaining trees as it allows a nation's ecosystem to function properly and also helps people live healthily and have a prosperous lifestyle. The Chipko movement quickly spread across communities and media, and forced the government, to whom the forest belongs, to rethink their priorities in the name of forest produce. Due to the participation of local people, it led to the efficient management of forests.
One of the movement's major successes was that the Uttar Pradesh government ensured zero tolerance for commercial forest felling and saved thousands of trees from being felled, which resulted in the conservation of abundant forest resources for local benefits.
The Chipko movement was a movement in India to protect forests. Thus, individuals took up this campaign and organised a number of demonstrations to raise people's consciousness. They protested against logging operations for trade. And deforestation has finally been stopped.

Question. What changes can you make in your habits to become more environmentallyfriendly?
Answer: We can make the following changes in our habits:
(a) We can segregate biodegradable and non-biodegradable wastes and dispose them in separate dustbins.
(b) We can collect paper, plastics, metals, glass apparatus and recycle them to make new products.
(c) By closing the water taps and repairing leaky pipes and taps on time to save water.
(d) By switching off lights, fans, computer, television etc., when not in use.
(e) By using solar energy for cooking, heating water etc., instead of using fossil fuels.
(f) By planting more trees.
(g) By reusing things instead of throwing away. Example – old clothes, toys etc., can be given to needy people, plastic bottles of jam, pickles can be used to store other things etc.

Question. Suggest ways to strike a balance between environment and development?
Answer:
(a) Use of renewable sources of energy instead of nonrenewable sources.
(b) Large scale afforestation programmes should be carried out and use of forest resources effectively.
(c) Segregation of biodegradable and non-biodegradable wastes and use of recycling technology for efficient use of resources.

Long Answer Type Questions :

Question. Differentiate between watershed management and Water Harvesting.
Answer: 
 

Question. How can you as an individual contribute or make a difference to the management of: 
(i) Forests and wildlife
(i) Water resources
(i) Coal and petroleum
Answer:
(i) Forests and wild life:
(a) Large scale afforestation programmes.
(b) Avoid cutting down of trees.
(c) To educate people about the importance of forests by organising events, programs and campaigns.
(ii) Water resources:
(a) By closing the water taps and repairing leaky pipes and taps to save water.
(b) Harvesting and conserving water.
(c) Avoid polluting water and create awareness among people to save water.
(iii) Coal and petroleum:
(a) Minimum utilisation of fossil fuels and using more alternative sources of energy like solar energy.
(b) We can use public transport instead of our personal vehicles.
(c) We can walk to nearby places instead of using vehicles.
(d) Proper maintenance of vehicles and use of efficient internal combustion engines.
(e) Use of CNG instead of petrol or diesel.

Question. The environmentalists are insisting upon “sustainable natural resource management”. State its advantages ?
Answer: The advantages of sustainable natural resource management are :
(a) It provides resources for the benefit of both present and future generations.
(b) It would reduce pollution and helps in conservation ofnatural resources.
(c) It enables equal distribution of resources to everyone whether rich or poor.
(d) It provides steady economic growth and misuse of natural resources.

Question. List few problems that may arise by planting trees of single variety over vast tracts of forest?
Answer: The problems which arise by planting trees of single variety over vast tracts of forest are:
(a) Loss of biodiversity.
(b) Various needs of the local people cannot be met by monoculture.
(c) If a disease occurs to that particular plant it would affect large areas.
(d) Different organisms require different types of food from different plants but if one variety of plants is planted many organisms will not get food.

Question. Answer the following: 

(i) Locate and name the water reservoirs in figure A and B.
(ii) Which has an advantage over the other and why?
Figure (A) Figure (B)
Answer:
(i) A is pond and B is underground water body.
(ii) Underground water body has an advantage over pond as:
(a) Water is lost by evaporation.
(b) Water does not get contaminated due to human activities.
(c) It does not serve as a breeding place for mosquitoes, flies which are carriers of several diseases.
(d) It provides moisture for vegetation over a large area.
(e) It spreads out to recharge wells.

♦ Natural Resources :-

Very Short Answer Type Questions

Question. What is a natural resource?
Answer : All the material we obtain from nature and use it is called natural resource.

Question. What are 3 R’s used to save environment?
Answer : Reduce, Recycle and Reuse.

Question. Name the bacteria whose presence in the water indicates its contamination with disease causing microbes.
Answer : Coliform bacteria.

Question. State 2 advantages of constructing dam across a river.
Answer : It helps in generating electricity in irrigation.

Question. Who started the “Chipko Movement”?
Answer : Sunderlal Bahuguna.

Question. Name the gas responsible for global warming.
Answer : Carbon dioxide and methane.

Question. Name any one stake holder.
Answer : Bishnoi community in Rajasthan.

Question. What are the products formed when coal and petroleum are burnt?
Answer : Carbon dioxide, water, oxides of nitrogen and oxides of sulphur.

Short Answer Type Questions

Question. How does mining cause pollution?
Answer : Mining causes pollution because if produces large amount of slag which is discarded for every tonne of metal that is extracted.

Question. For the conservation of forest who can be a stakeholder.
Answer : (i) The people who live in or around forest.
(ii) The forest department of the government.
(iii) The industrialists.
(iv) The wildlife and nature enthusiasts who want to conserve nature.

Question. Name two industries based on forest produce.
Answer : Paper industries, bamboo, bidi and tendu leaves industries.

Question. What is water harvesting? What is the main purpose of water harvesting?
Answer : Rain water harvesting is collecting the rain water, allowing it to percolate, discharge down the earth and increase the ground water level. It is done to manage water.

Question.  A tribe is living near the forest. Name two things which they will commonly use from forest.
Answer : Tribe will use timber, firewood, fruits, gum, medicines from the forest.

Question. Write two advantages of classifying sources as renewable and non-renewable.
Answer : Classification of resources helps us in deciding the kind of resource we should use judiciously and wisely. The resource that is not limited. It also helps us to know the importance of using renewable source of energy.

Question. Explain 3R’s with one example each.
Answer : Reduce—Less use of products like paper, clothes, plastic, wood, coal, petroleum so that it is not exploited from the nature.
Recycle—To make new items from the used articles like plastic, paper, wood, glass etc.
Reuse—Use the same thing again and again. E.g., use the jam and pickle containers for keeping kitchen stuff etc.

Question. What are the advantages of water stored in ground?
Answer : (i) Does not evaporate.
(ii) Recharges wells.
(iii) No danger of mosquito breeding.
(iv) Better availability of potable water.

Question. What are three basic cause that has brought criticisms about large dams projects?
Answer : (i) Social problem—as its construction displaces large number of tribals and local peasants without proper compensation and rehabilitation.
(ii) Economic problem—such projects need lot of money for the setup or construction without much of out-put or benefit.
(iii) Environmental problem—the construction causes deforestration and loss of biological diversity.

Question. List two traditional system of water harvesting. 
Answer : Khadim, tanks and nadis in Rajasthan, bandharas and tals in Maharashtra.

Question. What are fossil fuels? How are they formed? Why should we use them judiciously?
Answer : Fossil fuels are obtained from the remains of plants and animals which got burried under the earth some millions of year ago. They changed into fuel due to tremendous heat and pressure.
The fossil fuels should be used judiciously because they are non-renewable resources, and can not be made again. It releases harmful and polluting gases like CO₂, which causes green house effect and oxides of nitrogen and sulphur which causes acid rain.

Question. What is rain water harvesting? How can it be done at local level? What are its benefits?
Answer : Rain water harvesting is the indigenous water saving methods to capture every trickle of water that had fallen on land. For this we need to dig small pits and lakes, build small earthen dams, construct dykes, sand and lime stone reservoirs, set up roof top water collecting units. This will recharge ground water levels and bring rivers back to life.
Water harvesting techniques give people control over their local water resources, ensures, that the mismanagement and over exploitation of these resources is reduced/removed.
The advantage of water stored in the ground are many. It does not evaporate, but spreads out to recharge wells and provide moisture for vegetation over a wide area.
It does not provide breeding area for mosquitoes. It is also protected from contamination by human and animal waste.

Value Based Questions

Question. Pritam stays in a village near a forest. He plays the best role of being a stakeholder of the forest by taking care of it, reporting on illegal cutting down of trees and forest fire etc.
(a) Name two industries based on forest produce.
(b) Give two causes of forest depletion in India.
(c) What values are reflected in Pritam?
Answer : (a) Paper, timber.
(b) Deforestation and forest fires.
(c) Pritam shows the values of personal responsibility and participating citizenship.

Question. Today we encounter the problem of water shortage, although it rains well in rainy season.
‘Khushi society’ has made a provision of rainwater harvesting.
(a) Suggest two methods of rain water harvesting.
(b) How can you store water without any water-borne diseases and germs multiplying in it?
(c) What values are seen in the members of society?
Answer :  (a) Roof top and underground rain water harvesting.
(b) In close tanks and underground tanks.
(c) Members show responsible behaviour, socially just interaction and team work.