Topic outline

    • Water: A Precious Resource

      Q16. How increasing industries are responsible for depletion of water table?

      Ans. Water is used by all the industries. Almost everything that we use needs water somewhere in its production process. The number of industries is increasing continuously. Water used by most of the industries is drawn from the ground.

       

      Q17. Explain how groundwater is recharged?

      Ans. The rainwater and water from other sources such as rivers and ponds seeps through the soil and fills the empty spaces and cracks deep below the ground. The process of seeping of water into the ground is called infiltration.

      The groundwater thus gets recharged by this process.

       

      Q18. What will consequences if water is not available to plants?

      Ans. Plants need water to get nutrients from the soil to prepare their food. If water is not available to plants, the green character of the planet shall be lost. This may mean the end of all life, for a world without plants shall mean no food, no oxygen, not enough rain, and innumerable other problems.



      Q19. Why are we left only tiny fraction of water for use even if about 71 % of the earth surface is covered with water?

      Ans. 71% of the earth’s surface is covered with water. Almost all the water on the earth is contained in the seas and oceans, rivers, lakes, ice caps, as groundwater and in the atmosphere. However, most of this water is not fit for human consumption. The water that is fit for use is fresh water.

       

      Q20. Explain the three form of water that exists in nature.

      Ans. Water exists in three forms: solid, liquid and vapour. The solid form, snow and ice, is present as ice caps at the poles of the earth, snow-covered mountains and glaciers. Liquid water is present in oceans, lakes, rivers, and even underground. The gaseous form is the water vapour present in the air around us.

       

      Q21. From where do people in villages get water?

      Ans. Many villages do not have water supply system. There people fetch water directly from the sources. Often women and children have to walk several kilometres to fetch water. The children suffer a lot. They cannot attend school regularly since they spend hours in fetching water.  A large number of people draw water from wells, tube wells or hand pumps.

       

      Q22. List some methods to conserve water.

      Ans. Methods to conserve water

                                i.        Repairing leaking supply pipes and taps.

                               ii.        Judicially using water while brushing teeth, shaving, bathing, washing and during many other activities.

                              iii.        Water harvesting

                              iv.        Drip irrigation



      Q23. Can we keep on drawing water from under the ground? How will it affect the water table?

      Ans. Water drawn from under the ground gets replenished by seepage of rainwater. The water table does not get affected as long as we draw as much water as is replenished by natural processes. However, water table may go down if the water is not sufficiently replenished.

       

      Q24. What are the reasons for lowering of the water table?

      Ans. This may happen due to many reasons. Increase in population, industrial and agricultural activities are some common factors affecting water table. Scanty rainfall is another factor that may deplete the water table. Yet another factor affecting water table could be deforestation and decrease in the effective area for seepage of water.

       

      Q25. Why is distribution of water uneven in our country?

      Ans. India is a vast country and the rainfall is not the same everywhere.

      Some regions have excessive rains while some others have very little rainfall. Excessive rains cause floods, whereas the absence of rains results in droughts. Therefore, some regions in our country may have floods while others may suffer from droughts at the same time.

       

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