NCERT Solutions For Class 12 Geography Part B Chapter 4 Water Resources

Q. Choose the right answers of the followings from the given options:

(i) Which one of the following types describes water as a resource?

  • (a) Abiotic resource
  • (b) Non-renewable Resources
  • (c) Biotic Resource
  • (d) Cyclic Resource
  • Ans. (d) Cyclic Resource

(ii) Which one of the following south Indian states has the highest groundwater utilisation (in per cent) of its total ground water potential?

  • (a) Tamil Nadu
  • (b) Karnataka
  • (c) Andhra Pradesh
  • (d) Kerala
  • Ans. (a) Tamil Nadu

(iii) The highest proportion of the total water used in the country is in which one of the following sectors?

  • (a) Irrigation
  • (b) Industries
  • (c) Domestic use
  • (d) None of these
  • Ans. (a) Irrigation

Q. Answer the following questions in about 30 words:

(i) It is said that the water resources in India have been depleting very fast. Discuss the factors responsible for the depletion of water resources?

Ans. The per capita availability of water is dwindling day by day due to the increase in population. The available water resources are also getting polluted with industrial, agricultural, and domestic effluents, and this, in turn, is further limiting the availability of usable water resources. Some states utilise a large proportion of their groundwater potential which has resulted in groundwater depletion in states like Punjab, Haryana, and Uttar Pradesh.

(ii) What factors are responsible for the highest groundwater development in the states of Punjab, Haryana and Tamil Nadu? x`

Ans. The states of Punjab, Haryana, and Tamil Nadu have agriculture supported mainly by irrigated water and the main source for it is underground water. These regions were the target regions for the green revolution. All the green revolution crops are water-intensive, hence the demand for water in these states is very high. Groundwater is overutilised in these states for the purpose of irrigation which has led to the decline in groundwater table in these states.

(iii) Why the share of agricultural sector in total water used in the country is expected to decline?

Ans. In recent times the share of secondary and tertiary activities has been rising in the economy. This will reduce the share of the agricultural sector and increase the share of the industrial and domestic sector in the consumption of all resources including the water resources of the country.

(iv) What can be possible impacts of consumption of contaminated/unclean water on the people?

Ans. Contaminated water intake is one of the biggest reasons for many chronic diseases. The intake of contaminated water is the cause of severe water borne disease and is also one of the main causes of high infant mortality rates. Contaminated water is the reason for several diseases like Cholera, typhoid, etc. which are among the major and common diseases in India.

Q. Answer the following questions in about 150 words.

(i) Discuss the availability of water resources in the country and factors that determine its spatial distribution?

  • Ans. 1. Surface water resources: There are four major source of surface water such as rivers, lakes, ponds and tanks. The mean annual flow in all river basin in India is estimated to be 1869 cubic km. Only 690 cubic km of the available surface water can be utilised. There surface water resource generally depend on precipitation. In India rainfall or precipitation varies across the country. Example almost whole year of river Ganga, Bramhputra are full of water. But in Southern river like Krishna, Godaveri, depend on monsoon season.
  • 2. Ground water resource: The total replenishable ground water resource in India are 432 cubic km. The utilisation of groundwater is relatively high in North-Western region and some part of the South India.
  • 3. Lagoons: The state like Kerala, Odisha and West Bengal have vast surface water resource in the Lagoons and lake.

(ii) The depleting water resources may lead to social conflicts and disputes. Elaborate it with suitable examples?

Ans. It can be said with some certainty that due to the depletion of water resources, societies will witness demographic transition, a geographical shift of population, technological advancement, degradation of the environment, and water scarcity. Water scarcity is possible to pose the greatest challenge on account of its increased
demand coupled with shrinking supplies due to overutilisation and pollution. Water is a cyclic resource with abundant supplies on the globe. Approximately, 71% of the earth’s surface is covered with it but freshwater constitutes only about 3% of the total water. In fact, a very small proportion of freshwater is effectively available
for human use. The availability of freshwater varies over space and time. The tensions and disputes on sharing and control of this scarce resource are becoming contested issues among communities, regions, and states. It is the scarcity of water that has caused longstanding disputes between the state of Karnataka and Tamil Nadu over sharing of waters of the Kaveri River. Sharing of water of Brahmaputra has always been a cause of conflict between India and Bangladesh. Much to India’s dislike and concern China is planning to build a dam on river Brahmaputra.

(iii) What is watershed management? Do you think it can play an important role in sustainable development?

  • Ans. 1. Watershed management refers to efficient management and conservation of surface and groundwater resources with community participation. It involves the prevention of runoff and storage and recharge of groundwater through various methods like percolation tanks, recharge wells, etc.
  • 2. Yes, watershed management plays an important role in sustainable development. It includes conservation, regeneration, and judicious use of all resources – natural (like land, water, plants, and animals) and human within a watershed. Watershed management aims at bringing about a balance between natural resources on the one hand and society on the other. The success of watershed development largely depends upon community participation. The Central and State Governments have initiated many watershed development and management programs in the country like “Hariyali”, “Neeru-Meeru”, and “Arvary Pani Sansad”. Watershed development projects in some areas have been successful in rejuvenating environment and economy. There is a need to generate awareness regarding benefits of watershed development and management among people in the country, and through this integrated water resource management approach water availability can be ensured on sustainable basis.