Q. 1. Define catchment area.
Ans. The area from which rainfall flows into a river, lake or reservoir is called a catchment area.
Q. 2. Define a lagoon.
Ans. An area of shallow body of water separated from the sea by barrier islands or reefs.
Q. 3. Define groundwater.
Ans. Water held underground in the soil or in pores and crevices in rocks is called as groundwater.
Q. 4. India accounts for how much of the world’s water resource?
Ans. India accounts for 4 per cent of the world’s water resource.
Q. 5. Name any two major sources of water resources.
Ans. Rivers, lakes, ponds and tanks are the major source of water resources.
Q. 6. Water flow in the river depends on what basic factor?
Ans. Water flow in the river depends on the size of its catchment area or river basin and the rainfall within its catchment area.
Q. 7. Name any two rivers which have huge catchment areas.
Ans. Ganga, Brahmaputra and Indus.
Q. 8. Name the states where the groundwater utilisation is very high.
Mention any two states where groundwater level utilisation is very high.
Ans. Punjab, Haryana, Rajasthan and Tamil Nadu.
Q. 9. Name the states which utilise very small proportion of their groundwater potentials.
Ans. Chhattisgarh, Odisha and Kerala.
Q. 10. What is the percentage of Earth covered with water?
Q. 11. Which sector grounds for most of the surface and groundwater utilisation?
Q. 12. Explain the importance of irrigation for agriculture in India.
Ans. Importance of irrigation:
(i) Control of drought and famines: Insufficient, uncertain and irregular rain causes uncertainty in agriculture. Even during monsoon, the rainfall is scanty and undependable in many parts of the country.
Sometimes, the monsoon get delayed considerably while sometimes they cease prematurely. This pushes large areas of the country into drought conditions. With the help of irrigation, droughts and famines can be effectively controlled.
(ii) Higher productivity on irrigated land: Productivity on irrigated land is considerably more than the productivity on unirrigated land.
(iii) Multiple cropping possible: Provision of irrigation facilities can make the growing of two or three crops in a year in most areas of the country. This will considerably enhance agriculture production and productivity.
(iv) Role in new agricultural strategy: The successful implementation of the High Yielding Programme enhances agricultural production to a great intent. This has been made possible due to the expansion of irrigation facilities.
Q. 13. Study the given diagram and answer the questions that follow:
1. Which sector accounts for most of the groundwater utilisation? Give one reason.
2.Why is the share of water utilisation in domestic sector lower in groundwater as compared to surface water?
Ans. 1. Agricultural sector because India is an agriculture based country.
2. Because underground water is not available in most of these areas.
Q. 14. What factors are responsible for the highest groundwater development in the states of Punjab, Haryana and Tamil Nadu?
Ans. (i) The groundwater utilisation is very high in the states of Punjab, Haryana and Tamil Nadu because these states are advanced agricultural states.
(ii) Water is used mainly in irrigation. The share of agriculture sector in total water utilization is much higher than other sectors. Irrigation is needed because of spatio-temporal variability in rainfall in the states.
(iii) The larger tracts of the country are deficient in rainfall and are drought prone. Further, the high yielding varieties of crops need regular moisture supply, which is made possible only by a developed irrigation system.
Q. 15. Why has development of irrigation assigned a very high priority in the Five Year Plans?
Ans. About two-thirds of its population have been dependent on agriculture. Hence, development of irrigation to increase agricultural production has been assigned a very high priority in the Five Year Plans.
Q. 16. Name any two multipurpose river valley projects.
Ans. Bhakra-Nangal, Hirakud, Damodar Valley, Nagarjuna Sagar and Indira Gandhi Canal Project.
Q. 17. What accounts for most surface and groundwater utilisation?
Q. 18. Why is irrigation needed in our country?
Ans. Irrigation is needed because of the spatio-temporal variability in rainfall in the country.
Q. 19. What has intensive irrigation in Punjab, Haryana and Uttar Pradesh resulted into?
Ans. It has resulted into increasing salinity in the soil and depletion of groundwater irrigation.
Q. 20. What are the implications of using ground- water resources water in drought prone area of Rajasthan, Gujarat, Maharashtra and Tamil Nadu?
Ans. It has increased the fluoride concentration in the groundwater.
Q. 21. Which state makes use of highest percentage of tubewell water?
Ans. Gujarat , 86.6 percentage.
Q. 22. Why is irrigation required? Give one reason.
Ans. Irrigation is required because of variability in rainfall in the country.
Q. 23. Why the share of agriculture sector in total water used in the country is expected to decline?
Ans. The share of agricultural sector in total water used in the country is expected to decline because other sectors such as industry are progressing at a much faster pace than agriculture sector and the consumption of water in these sectors is likely to increase.
Q. 24. Study the data of percentage of net irrigated area to total by wells and tube-wells given below and answer the questions:
(i) Which state has maximum percentage of net irrigated area to total by well and tube-wells?
(ii) What are the implications of excessive use of groundwater?
Ans. (i) Gujarat.
(ii) To over-use of groundwater resources had led to decline in groundwater table in these states.
In fact, over withdrawals in some states like Rajasthan, and Maharashtra has increase fluoride concentration in groundwater, and this practice has led to increase in concentration of arsenic in parts of West Bengal and Bihar.
Q. 25. Mention any two sources of water pollutants created by humans.
Mention any two sources of water pollution in India.
Name any two natural sources of water pollutants.
Ans. (i) Sewage disposal.
(ii) Urban run-off.
(iii) Toxic effluents from industries.
(iv) Run-off over cultivated lands and nuclear power plants.
Q. 26. Name any two natural sources of water pollutants.
Ans. (i) Erosion
Q. 27. Why is the per capita availability of water dwindling day by day?
Ans. The per capita availability of water is dwindling day by day due to the increase in population.
Q. 28. What does water quality refer to?
Ans. Water quality refers to the purity of water or water without unwanted foreign substances.
Q. 29. How do the toxic substances pollute the water?
Ans. The toxic substances enter the lakes, streams, rivers, oceans and other water bodies, they get dissolved or lie suspended in water. This results in pollution of water.
Q. 30. Mention any two uses of river water in the plains.
Ans. River water is used for irrigation, drinking, domestic and industrial purposes.
Q. 31. Name the two boards that have been monitoring the water quality of national aquatic resources.
Ans. The Central Pollution Control Board (CPCB) and State Pollution Control Boards have been monitoring the water quality of national aquatic resources.
Q. 32. Mention any two cultural activities that are responsible for water pollution in India.
Ans. The cultural activities which are responsible for water pollution are:
(i) Pilgrimage, religious fair held near the river bank and tourism.
(ii) Dispersal of idols, ashes, dead bodies etc.
Q. 33. Mention two highly polluted rivers in India.
Ans. Ganga and Yamuna.
Q. 34. Which is the most significant contributor of water pollution in India?
Ans. The most significant contributor of water pollution in India is untreated sewage.
Q. 35. Mention any two sources of water pollution by human beings in India.
Ans. The two sources of water pollution by human beings in India are as follows:
(i) The urban sources of polluted water and sewage, municipal and domestic garbage that is disposed into the water.
(ii) The disposal of industrial effluents into the running water which makes the water body degraded and poisonous.
Q. 36. Name any two water conservation techniques adopted in India.
Ans. Two water conservation techniques are Rainwater harvesting and Watershed development.
Q. 37. “The assessment, efficient use and conservation of water are necessary to ensure development.” Explain in the light of values regarding conservation of water resources.
Ans. Conservation of water resources is necessary because:
(i) There is a vast disparity between population and availability of water resources as India has about 16 per cent of world’s population, but has only 4 per cent of world’s water resources.
(ii) The total utilisable water resources in India are very limited.
(iii) Population is increasing at a faster rate and the demand is also increasing day by day.
(iv) Pollution is making water resource unusable.
Human values like responsibility, positive approach, awareness, contentment, cooperation and active citizenship are needed for conservation of water resources.
Q. 38. Explain with examples, how the industries are responsible for polluting water resources in India.
Ans. The dumping of industrial waste into rivers leads to water pollution. Industries generate ordinary domestic sewage that can be treated by municipal facilities but those industries that generate waste water with high concentration of conventional pollutants (e.g. oil and grease), toxic pollutants (e.g., heavy metals, volatile organic compounds) or other non-conventional pollutants such as ammonia are highly responsible for polluting the water resources. When these enter the water resources from industries, they deteriorate the quality of water and render it unfit for human use. This in turn limits the availability of usable water resources. Most industries in India do not follow the norms and let the waste water go into the river without the process of detoxification.
For example, The Yamuna river is the most polluted river in the country between Delhi and Etawah. This is just because industries between these two cities do not detoxify their waste water. Other severely polluted river is the Sabarmati at Ahmedabad.
Q. 39. Examine any three causes for the deterioration of ‘quality of water’ in India.
Ans. (i) Wastes caused by urbanisation and industrialisation.
(ii) Excessive use of pesticides in farming.
(iii) Rivers receive millions of litres of sewage, mining and industrial wastes.
Q. 40. Why is conservation of water resources necessary? Explain any three reasons.
Ans. (i) Water is the most essential component of life and is vital for sustenance. Without water people cannot live, without water plants cannot live, without water animal cannot live.
(ii) Level of groundwater is decreasing day by day. It leads to the scarcity of potable drinking water.
(iii) Our wildlife has no choice but to depend on the nearest stream, lake or pond for its water whether its polluted or not. The effects of water pollution on human health can be deadly. With your help, we can assure that watersheds across the country are clean, healthy and meet the needs of the wildlife and the people that depend on them.
Q. 41. Describe any three major problems related to water in India.
Ans. Major problems related to water in India are:
(i) Water scarcity: Water demand in India is roughly distributed as follows: 90% agriculture, 5-6% industry and rest of domestics and other uses.
Demand from domestic and industry sources is expected to increase with the growth in economy and population.
(ii) Depletion of groundwater: Underground water accounts for close to 50% of irrigation needs and most of the rural domestic needs. Whenever the rate of extraction is more than the rate of replenishment, depletion of aquifers take place.
(iii) Water pollution, a very serious problem in India with over 70% of surface water and lot of groundwater sources polluted with biological toxic organic and inorganic wastes.
Q. 42. What can be possible impacts of consumption of contaminated/unclean water on the people?
Ans. Impacts of consumption of contaminated/unclean water on the people:
(i) Water-borne diseases spread primarily through contaminated water. About 80% of the stomach diseases in India happen due to consumption of unclean water.
(ii) Most intestinal diseases are caused by consuming contaminated water.
(iii) People can get hepatitis, cholera, dysentery and typhoid if they consume unclean water.
Q. 43. How can we conserve water resources?
Ans. (i) Water should be reused and recycled to maximise its usage.
(ii) Rainwater should be harvested to meet water requirements.
(iii) Drip irrigation and sprinkler system should be used for irrigation.
(iv) In urban areas, water after bathing and washing utensils should be used for gardening.
Q. 44. ‘‘Indiscriminate use of water by increasing population and industrial expansion has led to degradation of the quality of water considerably.’’ Evaluate the statement.
Ans. Increasing population and industrial expansion are responsible for water pollution:
(i) Domestic and sewage waste water remains untreated.
(ii) Excessive use of fertilizers and pesticides in farming results in water pollution.
(iii) Cultural activities: fairs, tourism, pilgrimage, etc.
(iv) Industries produce many undesirable substances which pollute water.
(v) Chemical residues and toxins pollute water.
(vi) Major polluting industries are leather, pulp, paper, textiles, chemicals, etc.
(vii) Any other relevant point.
Increasing population and industrial expansion are responsible for water pollution:
(i) Domestic and sewage waste water remains untreated: Humans have decided to expand their cities and towns into parts of the environment that were previously uninhabited. The haphazard expansion has led to poor planning of disposing the domestic and industrial litter which often finds its way into water resources hence causing water pollution.
(ii) Excessive use of fertilizers and pesticides in farming results in water pollution: Excessive use of fertilizers and pesticides can cause water pollution. It is important to adapt environmental friendly agricultural practices to avoid water pollution.
(iii) Cultural activities (fairs, tourism, pilgrimage, etc): Human activities such as fairs, pilgrimages also cause water pollution by releasing many pollutants in the water thus causing a lot of harm to it.
(iv) Industries produce many undesirable substances which pollute water: When it comes to water pollution, fuel emission, toxic chemicals released by the industries have an adverse effects on the water around it. Any type of fuel released or burnt by the industries near the water body causes carbon dioxide to enter that resource and hence cause water pollution.
(v) Chemical residues and toxins pollute water: Fossil fuels are known to cause lead contamination in water sources which is very dangerous not only for marine life but also for humans who happen to drink or swim in that water.
(vi) Major polluting industries are-leather, pulp, paper, textiles, chemicals, etc: The leather, pulp, textiles and chemical industries also cause the presence of bacteria to increase the pollution level in the water. In many cases, the factory operations can cause water temperature to rise or fall and when this happens, it becomes more likely for bacteria growth to take place.
Q. 45. Define the term ‘watershed management.’
Ans. Watershed management is the term used to describe the process of implementation land use practices and water management practices to protect and improve the quality of water and other natural resources within a watershed by managing the use of those land and water resources in a comprehensive manner.
Q. 46. Define rainwater harvesting.
Ans. Rainwater harvesting is a method to capture and store rainwater for various uses.
Q. 47. What determines the success of watershed development?
Ans. Community participation determines the success of watershed development. 1
Q. 48. What do you know about Haryali?
Ans. Haryali is a watershed development project sponsored by the Central Government which aims at enabling the rural population to conserve water for drinking, irrigation, fisheries and afforestation.
Q. 49. What projects have been taken up by Neeru-Meeru and Arvary Pani Sansad?
Ans. These programmes have taken up the constructions of various water harvesting structures such as percolation tanks, dug out ponds, check dams, etc.
Q. 50. What does watershed management include?
Ans. Watershed management includes conservation, regeneration and judicious use of all resources — natural and human.
Q. 51. How can the quality of water be improved?
Ans. Quality of water can be improved by:
(i) Judicious use of water
(ii) Creating awareness - importance of water.
Q. 52. Who sponsored Hariyali programme?
Ans. The Central Government.
Q. 53. What is the local name of rainwater harvesting structure in Rajasthan?
Ans. Kund or Tanka.
Q. 54. Explain watershed management. What is its aim?
What is watershed management ? Do you think it can play an important role in sustainable development ?
Ans. Watershed management is the study of the relevant characteristics of a watershed aimed at the sustainable distribution of its resources and process of creating and implementing plans, programs and projects to sustain and enhance watershed functions that affect the plant, animal and human communities within a watershed boundary. Features of a watershed that agencies seek to manage include water supply, water quality, drainage, storm water runoff, water rights and the overall planning and utilisation of watersheds.
Landowners, land use agencies, storm water management experts, environmental specialists, water use surveyors and communities all play an integral part in the management of a watershed.
Q. 55. Define the term ‘Rainwater Harvesting’. Mention any four advantages of rainwater harvesting.
Ans. Rainwater harvesting is the accumulation and storage of rainwater for reuse on-site , rather than allowing it to run off.
The four advantages of rainwater harvesting are:
(i) It is a low cost and eco-friendly technique for preserving every drop of water.
(ii) it increases water availability and checks the declining groundwater table.
(iii) It prevents soil erosion and flooding.
(iv) It can also save energy to pump groundwater as recharge leads to rise in groundwater table.
Q. 56. What values can help us in maintaining the quality of water?
Ans. The values that can help in maintaining the quality of water:
(i) Judicious/optimum use of water
(ii) Controlling population
(iii) Recycle and reuse of water
(iv) Watershed management
(v) Rainwater harvesting
(vi) Rules and regulations
(i) Recycle and reuse of water: One of the ways through which we can improve fresh water availability is by recycle and reuse. Use of water of lesser quality such as reclaimed waste-water would be an attractive option for industries for cooling and fire fighting to reduce their water cost. Similarly, in urban areas water after bathing and washing utensils can be used for gardening. Water used for washing vehicle can also be used for gardening. This would conserve better quality of water for drinking purposes.
(ii) Watershed management: Watershed management basically refers to efficient management and conservation of surface and groundwater resources. It involves prevention of runoff and storage and recharge of groundwater through various methods like percolation tanks, recharge wells, etc. However, in broad sense watershed management includes conservation, regeneration and judicious use of all resources – natural (like land, water, plants and animals) and human with in a watershed.
(iii) Rainwater harvesting: Rainwater harvesting is a method to capture and store rainwater for various uses. It is also used to recharge groundwater aquifers. It is a low cost and eco-friendly technique for preserving every drop of water by guiding the rain water to bore well, pits and wells. Rainwater harvesting increases water availability, checks the declining groundwater table, improves the quality of groundwater through dilution of contaminants like fluoride and nitrates, prevents soil erosion, and flooding and arrests salt water intrusion in coastal areas, if used to recharge aquifers.
Q. 57. What are the aims of rainwater harvesting?
Ans. The aims of rainwater harvesting are:
(i) To increase the water availability.
(ii) To check the declining groundwater table.
(iii) To improve the quality of groundwater through dilution of contaminants, like fluoride and nitrate..
(iv) To prevent soil erosion and flooding.
(v) To decrease the community dependence on ground water for domestic use.