NCERT Class 10 Geography Chapter 3 - Water Resources

Chapter 3 Water Resources

Question and Answers
Question 1: What are the quantitative and qualitative aspects of water scarcity?
Answer:
→ Quantitative aspect of water scarcity:
• Water scarcity may be an outcome of large and growing population and consequent greater demands for water, and unequal access to it.
• A large population means more water not only for domestic use but also to produce more food.
• Hence, to facilitate higher food-grain. production, water resources are being over-exploited to expand irrigated areas and dry-season agriculture.
• It may lead to falling ground water levels adversely affecting water availability and food security of people of the people.
• The ever-increasing number has made matters of industries has made matters worse by exerting pressure on existing freshwater resources.
• Industries, apart from being heavy users of water, also require power to run them. Much of this energy comes from hydroelectric power.
• Today, in India hydroelectric power contributes approximately 22% of the total electricity produced.
• Industries, apart from being heavy  users of water, also require power to run them. Much of this energy comes from hydroelectric power.
• Today in India hydroelectric power contributes approximately. 22% of the total electricity produced.

→ Qualitative aspect of water scarcity:
• This scarcity may be due to bad quality of water.
• There has been a growing concern that even if there is ample water to meet the needs of the people, much of it may be polluted by domestic and industrial wastes, chemicals, pesticides and fertilizers used in agriculture, thus, making it hazardous for human use.

Question 2: Why should we conserve water?
Answer: The need of the hour is to conserve and manage our water resources.
• To safeguard ourselves from health hazards.
• To ensure food security.
• Continuation of our and livelihoods productive activities.
• To prevent degradation of our natural ecosystems.
• Over exploitation and mismanagement of water resources will impoverish this resources and cause ecological crisis that may have profound impact on our lives.

Question 3: Compare the advantages and disadvantages of multi-purpose river projects.
Answer:
→ Advantages of multi-purpose river projects:
• Irrigation
• Electricity generation
• Domestic and industrial uses
• Flood control
• Recreation
• Inland navigation
• Fish breeding

→ Disadvantages of multi-purpose river projects:
• Regulating and damming of river affect their natural flow causing poor sediment flow and excessive sedimentation at the bottom of the reservoir.
• It controls the migration of aquatic fauna.
• It makes submergence of the existing vegetation.
• It leads to large scale displacement of local communities.
• It destroys habitat of millions of flora and fauna.
• It leads to the degradation of soil due to the continuous irrigation.

Question 4: Discuss how rainwater harvesting in semi-arid regions of Rajasthan is carried out.
Answer:
• In the semi-arid and arid regions of Rajasthan, particularly in Bikaner, Phalodi and Barmer, almost all the houses traditionally had underground tanks or tankas for storing drinking water.
• The tanks could be as large as big room.
• The tankas were part of the well-developed rooftop rainwater harvesting system and were built inside the main house or the courtyard.
• They were connected to the sloping roofs of the houses through a pipe.
• Rain falling on the rooftops would travel down the pipe and was stored in these underground 'tankas'.
• The first spell of rain was usually not collected as this would clean pipes. The rainwater from the subsequent showers was then collected.

Question 5: Describe how modern adaptations of traditional rainwater harvesting methods are being carried out to conserve and store water.
Answer:
• In ancient India, along with the sophisticated hydraulic structures, there existed an extraordinary tradition of water harvesting system.
• In hill and mountainous regions, people build diversion channels like the 'guls' or 'kuls' of the Western Himalayas for agriculture.
• 'Rooftop rainwater harvesting' was commonly practised to store drinking water, particularly in Rajasthan.
• In the flood plains of Bengal, people developed inundation channels to irrigate their fields.
• In arid and semi-arid regions, agricultural fields were converted into rain fed storage structures that allowed the water to stand and moisten the soil like the 'khadins' in Jaisalmer and 'jonads' in other parts of Rajasthan.