Embibe Experts Solutions for Chapter: Water: A Precious Resource, Exercise 1: Exercise

Shankar went to a science museum with his mother and saw several amazing scientific models. Shankar saw a model of earth there and noticed that the colour of our planet is mostly blue. Why is our earth blue, he questioned his mum. To this, she responded that water makes up the majority of our planet and that's why our planet is also called 'The blue planet'.
Shankar had some more doubts. Can you assist him in getting the answer for those? The questions are as follows:

a) Why is there a shortage of water even though whole earth is covered with water?

b) What are the causes of water scarcity in India?

Arun and his parents went for a two weeks trip during his summer vacations. One day, during the trip, Arun asked his mother about what would happen to the plants at their home. In response, his mother replied that it is most likely that most of the plants would perish if no one provided water for two weeks. For this reason, they have asked their neighbour to water the plants regularly. After finishing their trip after two weeks they all returned home. Arun saw that all the plants on their terrace were green and lively but one of the plant that was inside their house has gone dry and all its leaves have wilted.
From the above scenario it is clear that water is needed for the survival of plants. 

What will be the effect of water scarcity on plants and their environment?

Yogish and his friends are playing on the ground having a nice carpet of grass spread all over it. After a while, it started raining and the rain stopped after fifteen minutes. All of them noticed that the water on the ground was very less as compared to the amount that was poured during the rain.

Can you help Yogish by answering his following questions:
a) What happened to the rainwater? What do we call the method through which the water in this scenario disappears?

b) If the ground is made of cement instead of grass carpet, then what would be observed?

Reema is a student. Her mother informed her that her father was building a new home. This news makes Reema very delighted. She ran over to her father, hugged him, and talked to him about his interior designs and exterior views. Then suddenly a thought came to Reema's mind and Reema insisted that her father should install a rainwater harvesting system. Her father objected and said it will prove to be too expensive.

a) Who do you think is right, Reema or her father? Give a reason for your answer.

b) What are the values exhibited by Reema?

Rohith studied that water is a precious natural resource. Water is the most important substance for the survival of all living organisms. The organisms can survive longer without food, than without water. All organisms are composed of water, and it is important for various life activities such as excretion, digestion, etc. It is essential not only for sustaining life but also for agriculture, industry, energy production, and transportation.

Rohith decided that from now on he would drink plentiful of water as it is important for one's health. But when his mother spotted him drinking too much of water forcefully, she advised him not to drink too much water. Rohith was confused by this gesture of her mother. He had some questions; could you help him find the answers?

a) How many glasses of water should we drink daily?

b) If a person drinks a large amount of water in a short time, what will happen?

The water level under the ground is called the water table. It is the upper level of an underground surface in which the soil or rocks are permanently saturated with water. The water table varies from place to place, and it may even change within the same place. The water table falls during the summer and rises during the rainy season. The water table will fall if too much groundwater is withdrawn. This causes groundwater depletion. Groundwater depletion is the gradual and continuous lowering of the water table.

Discuss the various factors that have contributed to the depletion of the water table.

Mr. Prasanna is the president of his colony. He does not allow people to remove grass and plants and make the land concrete as this would adversely affect the water table. In their society meetings, he explains the importance of green areas for increasing the water table and the ill-effects of making land concrete.

From the above comprehension, answer the following questions:

1. Mention any two ways in which trees and forests help in maintaining the water table.

2. How does concrete land affect the water table?

Anu has always been very fond of flowers. She therefore planted a huge variety of flowering plants in her yard. She waters her plants every morning, after school, in the evening and also at night. As a result, Anu has developed the habit of overwatering the plants in her yard.

From the above, do you think that overwatering the plants could lead to groundwater contamination? If so, how?