Short Answer Questions - I - 2 Marks
Que 1. What are natural resources? State two factors that work against an equitable distribution of these resources.
Ans. Natural resources are the stocks of nature whether living or non-living, such as air, water, soil, animals and plants which are useful to the mankind.
Two factors that work against an equitable distribution of these resources are:
(i) money and (ii) power.
Que 2. What is meant by three types of 'R' (3-R's) to save the environment? Explain with examples how would you follow the 3-R's in your school to save the environment.
Ans. The three types of 'R' are Reduce, Reuse, Recycle. The 3-R's can be followed in the following ways:
-Switch off the fans and bulbs when not in use,
-Reuse of paper, polythene bags, etc.,
-Reduce the wastage of water/paper or any other item.
Que 3. Write two advantages of sustainable management of natural resources. Out of the two - reuse and recycle -which is better and why?
Ans. Advantages:
(i) Provides the resources for the present generation.
(ii) Preserves the resources for the future generation as well.
Reuse is better than recycling because it does not involve use of energy.
Que 4. Prepare a list of five items that you use daily in the school. Identify from the list such items that can be recycled.
Ans. Paper, rexine bag, blade, pen, plastic box, scale, eraser, compass and dividers (metallic), steel lunch box and steel spoon are used in the school.
Paper, blade, plastic box, eraser, compass, steel lunch box and steel spoon can be recycled.
Que 5. "The prejudice against the traditional use of forest areas have no basis". Explain.
Ans. The great Himalayan National park contains alpine meadows within its reserved areas. These meadows were grazed by sheep in summer. But after the formation of national park, this practice was stopped. Due to this, the grass first grows very tall and then falls over preventing fresh growth from below.
Que 6. What legislative measures are taken in India to conserve wildlife?
Ans. In India, several laws and acts have been passed from time to time in order to protect the degrading wildlife. Out of all, the Wildlife Protection Act of 1972 has been the most effective.
Under this Act, possession, trapping, shooting of wild animals alive or dead; serving their meat for eating in houses, using them as transport, etc, are completely under strict control or prohibited.
Que 7. Mention two ways in which water harvesting can be undertaken.
Ans. The two ways by which water harvesting can be undertaken are:
(i) Capturing run-off water from roof tops.
(ii) Capturing run-off water from local catchments.
Que 8. What is the impact of excessive irrigation and intensification of agriculture?
Ans. It has resulted in environmental degradation and creation of few waste lands. Water logging has ultimately caused development of saline soil.
Que 9. Building of big dams gives rise to some problems. List three main problems that may arise. Suggest a solution to any one of these problems.
Ans. (i) Social problems
(ii) Environmental problems
(iii) Economic problems.
Solution to these problems would be adequate rehabilitation, compensation to the displaced persons and afforestation.
Que 10. What measures would you take to conserve electricity in your house?
Ans. (a) Put off the fans and lights when they are not required.
(b) Maximum use of solar radiation.
(c) Use of solar water heating system during winters.
(d) Use of fluorescent tubes or CFL.
Que 11. What is Narmada Bachao Andolan?
Ans.
Que 12. (a) Why do we need to manage our resources carefully?
(b) Why management of natural resources requires a long term perspective?
Ans. (a) The resources are limited and with a tremendous increase in human population, the demand for resources is increasing at an exponential rate. Therefore, we need to manage them carefully.
(b) Long term perspective is required to meet the needs of the present as well as for the generations to come.
Que 13. Name any two endangered plant and animal species.
Ans. Endangered plant species-
Endangered animal species-Indian Wild Ass and Great Indian Rhinoceros.
Que 14. Name the river with which the following dams are associated.
(i) Tehri dam, (ii) Sardar Sarovar dam.
Ans. (i) Tehri dam on the river Ganga.
(ii) Sardar Sarovar dam on the river Narmada.
Que 15. Although coal and petroleum are produced by degradation of biomass, yet we need to conserve them. Why?
Ans. Both the energy sources, coal and petroleum, take millions of years for their formation. As these resources are being utilised at a much faster rate than their formation, they will be exhausted in the near future. Hence, they need to be conserved.
Que 16. Name a greenhouse gas produced due to combustion of fossil fuels. Mention its bad effect to the environment.
Ans. The greenhouse gases produced are CO2 and oxides of nitrogen and sulphur. These cause global warming.
Que 17. List two problems that may arise by planting trees of single variety over vast tracts of a forest.
Ans. (i) Loss of biodiversity
(ii) Varied needs of the local people can no longer be met.
(iii) Degradation of soil.
Que 18. What is water harvesting? How can this technique help in the conservation of water?
Ans. Water harvesting is a technique of capturing rain water when it falls and taking measures to keep the water clean.
This water is stored underground that remains unpolluted, it recharges wells and provides moisture for vegetation over a wide area.
Que 19. List two advantages associated with harvesting at the community level.
Ans. Advantages of water harvesting at community level:
(i) Recharges ground water
(ii) Mitigates floods and droughts.
(ii) Brings rivers and wells back to life and makes more water available.
Que 20. List any two advantages associated with water stored in the ground.
Ans. Advantages of water stored in ground:
(i) Recharges the ground water (ii) Prevents evaporation of water
(iii) Prevents breeding of mosquitoes (iv) Prevents contamination
(v) Mitigates flood and drought
Que 21. What is meant by "sustainable management"? Why is reuse considered better than recycling?
Ans. A type of management which encourages utilisation of resources that meet current basic human needs while preserving the resources for the needs of future generations is called sustainable management.
Reuse is better as it does not consume energy.
Que 22. List any two causes for the failure of sustained availability of ground water.
Ans. (i) Loss of vegetation cover.
(ii) Diversion for high water demanding crops.
(iii) Pollution from industrial effluents.
(iv) Dumping of urban waste. (Any two)