SEBA HSLC Class 10 | Chapter 16

Q1. What do you mean by river Dams? Mention its advantage and disadvantage.

Ans: River Dams are large water-holding structures built across rivers to control water flow.

Advantages of Dams

• Water from a dam is used for irrigation in fields through a network of canals.
• The construction of dams ensures a continuous water supply in the region.
• The falling water from the dam is used for generating electricity.

Disadvantages of Dams

• Social Problems: Due to the construction of high-rise dams, a large number of human settlements (or villages) are submerged in the water of a large reservoir formed by the dam, and many people are rendered homeless. This creates a social problem.
• Environmental Problems: The construction of high-rise dams on the rivers contributes to deforestation and loss of biodiversity. This is because a vast variety of flora and fauna (plants and animals) get submerged in the water of a large reservoir formed by the dam and disturb the ecological balance.
• Economic Problems: Some people say that the construction of high-rise dams involves the spending of a huge amount of public money without the generation of proportionate benefits.

Q2. What are the different types of processes used in India for water harvesting?

Ans: Methods of water harvesting in India:
  (i) The excess water collected through rainfall can be carried to the wells, which further helps to recharge the wells and underground water.
  (ii) Collection of rainwater on top of the roof and directing dry tanks.

Q3. Write short notes on 3R to save the environment.

Ans: The three Rs are reduce, recycle and reuse.
The term ‘reduce’ aims at lowering the usage of natural resources to avoid wastage. For example, using less electricity.
The term ‘recycle’ aims at using discarded items by recycling them. For example, recycling paper and plastic and sending them to the respective industries for the formation of new paper and plastic.
The term ‘reuse’ means using the same thing again and again. For example, using a paper bag over and over again.

Q4. Can you suggest some changes in your school which would make it environment friendly?
Answer:
Following changes can be made in schools to make it environment friendly.

1. Plant enough trees in the school.
2. Leaking taps should be repaired so that water is not wasted.
3. Bring food in reusable boxes, not in plastic bags or in aluminium foil.
4. Teachers can educate students about environmental conservation.
5. There should be more windows in school for natural light.