Something to Know
A. Fill in the blanks.
1. The earth is known as a blue planet.
2. Rain and snow are two major natural sources of water.
3. Setting-up of factories cause a decrease in the level of underground water.
4. Cutting of trees in the forests causes a decrease in rainfall.
5. Use of water sprinkler for irrigation reduces the wastage of water.
B. Match the following:
1. cutting of trees in the forests – (c) deforestation
2. collecting rain water for day-to-day use. (d) rain water harvesting
3. proper utilisation of water and avoiding its wastage (a) water conservation
4. a method of preserving large quantity of water and checking floods – (b) dam
C. Tick (✔) the correct option:
1. Two major natural sources of water are-
(a) rain and wells
(b) snow and rivers (✔)
(c) rain and snow
(d) ground water and rivers
Answer – (b) snow and rivers (✔)
2. Planting of more trees will help in-
(a) reducing the ground water level
(b) setting-up more factories
(c) deforestation
(d) increasing the rainfall (✔)
Answer – (d) increasing the rainfall (✔)
3. We can avoid wastage of water by-
(a) using water sprinkler for irrigation (✔)
(b) over-irrigation of fields.
(c) washing our car with a jet of water
(d) allowing water to leak from taps
Answer – (a) using water sprinkler for irrigation (✔)
D. Answer the following questions in brief.
1. How much of the surface of earth is covered by water?
Answer – Three-fourth of the surface of earth is covered by water.
2. Name three sources of fresh water.
Answer – Three sources of fresh water are rivers, streams and lakes.
3. State the effect of deforestation on rainfall.
Answer – The effect of deforestation on rainfall is it decreases the rainfall.
4. State two reasons that are leading to clearing of forests.
Answer – Two reasons that are leading to clearing of forests are :-
Setting up of factories.
For building houses.
5. State one utility of dams.
Answer – Dams stores large quantity of water.
E. Answer the following questions.
1. State three factors that are responsible for water scarcity.
Answer – Three factors responsible for water scarcity are-
Population
Setting up of factories
Deforestation
2. How does setting-up of factories affect the ground water level?
Answer – Setting up of factories affect the ground water level by following ways:-
Factories need a large quantity of water.
They fulfil this need by using underground water.
Hence, setting up of factories affect the ground water level.
3. State two ways to do rain-water harvesting.
Answer – Two ways to do rain water harvesting are:-
Rain water should be collected in large underground tanks from where it seeps slowly into the ground.
Rain water may also be collected overhead tanks and used for daily needs.
4. How should the fields be irrigated to reduce wastage of water?
Answer – Fields should be irrigated by using water sprinklers to reduce the wastage of water.
5. State any three ways of conserving water at home.
Answer – Three ways of conserving water at home are-
Turn off the tap after using it.
Use a mug and bucket to take bath instead of a shower.
Water the plants with a buckets and mugs instead of pipe.
Value Based Question
One day, when Aparna’s mother was cooking food, Aparna asked her if she could help her. Her mother asked Aparna to wash rice in a bowl with water. She then told Aparna to pour the used water in the plants in their garden. Aparna was a little surprised, but she followed her mother’s instructions. Later, on being asked, her mother explained why she had asked Aparna to pour the used water in plants.
1. What reason may have been given by Aparna’s mother?
Answer – Aparna’s mother does not want to throw the leftover water and wants to use this water for watering plants.
2. State the values displayed by Aparna and her mother.
Answer – Aparna and her mother wants to conserve water. They know the importance of water.
3. Suggest another way in which the used water could have been utilised.
Answer – Used water also utilised to wash vehicles, the cleaning toilets and for irrigation purpose.
Something to Do
1. Prepare a questionnaire about usage of water in daily life. Interview your friends/neighbours with the help of the questionnaire. Discuss the findings in the class with your teacher and friends.
A few questions are given below as samples:
(a) How do you wash your vehicle?
(b) How many buckets of water do you use for bathing?
(c) How do you water the plants?
You can frame more such questions for the questionnaire.
Answer – (a) What contribution you have in saving water?
(b) Do you have any formula or method to reuse dirty water for drinking?
(c) Say two slogans for conserving water.
(d) Why earth is called as a blue planet. Does it has any relation with water?
(e) Tell me five sources of water.
2. Celebrate ‘Water Conservation Day’ in your class. Divide the class into 4-5 groups. Each group should be given a responsibility, like making posters and slogans, putting these posters/slogans near water taps and bulletin boards in the school, staging a play, etc., to highlight the need for water conservation.
Answer – Students will do this task under the supervision of subject teacher.
3. Look at the pictures given below. Put a tick (✔) for the picture which shows saving of water and a cross (X) for the picture which shows wastage of water.