Water ResourcesClass 12 India - People And Economy NCERT Solutions
10 Solutions
Generated by KedovoAI
Solution 1 of 10
Q1EXERCISES
(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 the above
Solution
(a) Irrigation
The chapter clearly states that India's water demand is dominated by irrigational needs. It specifies that the agricultural sector, where water is primarily used for irrigation, "accounts for 89 per cent of the surface water and 92 per cent of the groundwater utilisation." This share is significantly higher than that of the industrial and domestic sectors, making irrigation the sector with the highest water usage.
Q1EXERCISES
(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
Solution
(a) Tamil Nadu
According to the chapter, the level of groundwater utilisation is relatively high in parts of south India. The text explicitly states, "The groundwater utilisation is very high in the states of Punjab, Haryana, Rajasthan, and Tamil Nadu." Among the South Indian states listed in the options, Tamil Nadu is mentioned as having very high utilisation, making it the correct answer.
Q1EXERCISES
(i) Which one of the following types describes water as a resource?
(a)
Abiotic resource
(b)
Non-renewable Resources
(c)
Biotic Resource
(d)
Non-cyclic Resource
Solution
(a) Abiotic resource
Water is classified as an abiotic resource because it is a non-living component of the ecosystem. The source text also states that "Water is a cyclic resource", which means it is renewable and can be replenished. This contradicts options (b) Non-renewable Resources and (d) Non-cyclic Resource. Since water is not a living organism, option (c) Biotic Resource is also incorrect. Therefore, the most appropriate description among the given choices is Abiotic resource.
Q2EXERCISES
(ii) What factors are responsible for the highest groundwater development in the states of Punjab, Haryana, and Tamil Nadu?
Solution
The high level of groundwater development in states like Punjab, Haryana, and Tamil Nadu is primarily driven by agricultural needs. The key factors are:
- Green Revolution: The success of the Green Revolution in Punjab and Haryana was dependent on High Yielding Varieties (HYV) of crops, particularly wheat and rice. These crops require a regular and assured supply of water, which was made possible through developed irrigation systems.
- Intensive Irrigation: These states have a very high percentage of their net sown area under irrigation. To meet the water requirements of crops, especially in the dry winter and summer seasons, farmers rely heavily on groundwater extracted through wells and tubewells. The text notes that in Punjab and Haryana, 76.1 per cent and 51.3 per cent of the net irrigated area, respectively, is irrigated through wells and tubewells.
- Agricultural Economy: In Tamil Nadu, similar to Punjab and Haryana, agriculture forms a significant part of the economy. The cultivation of water-intensive crops like rice necessitates extensive irrigation, leading to high utilisation of its groundwater potential.
Q2EXERCISES
(i) It is said that the water resources in India have been depleting very fast. Discuss the factors responsible for depletion of water resources?
Solution
The rapid depletion of water resources in India is due to several factors:
- Over-utilisation: There is excessive withdrawal of water, especially groundwater, to meet the demands of a growing population and for agricultural activities. States like Punjab and Haryana use a large proportion of their groundwater for irrigating water-intensive crops like rice and wheat, leading to a decline in the groundwater table.
- Increasing Demand: A rapidly growing population and economic development lead to an increased demand for water in domestic, industrial, and agricultural sectors. As per capita consumption rises, the pressure on existing water resources intensifies.
- Water Pollution: The quality of available water is deteriorating due to pollution from various sources. Industrial effluents, agricultural runoff containing fertilizers and pesticides, and untreated domestic sewage are discharged into rivers, lakes, and other water bodies. This contamination renders the water unfit for use, thereby reducing the availability of usable freshwater.
Q2EXERCISES
(iv) What can be possible impacts of consumption of contaminated/unclean water on the people?
Solution
Consumption of contaminated or unclean water can have severe impacts on human health. The possible impacts include:
- Water-borne Diseases: Unclean water often contains harmful micro-organisms and bacteria, which can cause diseases like cholera, typhoid, jaundice, and other gastrointestinal illnesses.
- Chemical Contamination: Industrial and agricultural pollutants can introduce toxic substances into the water. The chapter mentions that over-withdrawal of groundwater has led to increased concentrations of fluoride in Rajasthan and Maharashtra, and arsenic in parts of West Bengal and Bihar. Consumption of such water can lead to serious health problems like fluorosis (skeletal and dental damage) and arsenicosis (skin lesions, cancer).
- Overall Health Deterioration: Regular consumption of polluted water can weaken the immune system and negatively impact overall community health, leading to higher healthcare costs and reduced productivity.
Q2EXERCISES
(iii) Why the share of agricultural sector in total water used in the country is expected to decline?
Solution
The share of the agricultural sector in the total water used in the country is expected to decline in the future due to the increasing demands from other sectors. As India continues to develop economically, there will be significant growth in industrialisation and urbanisation. This development will lead to a substantial increase in the demand for water from the industrial and domestic sectors. While the absolute volume of water used for agriculture may remain high or even increase, its proportional share of the total water utilisation will decrease as the shares of the industrial and domestic sectors grow at a faster rate.
Q3EXERCISES
(ii) The depleting water resources may lead to social conflicts and disputes. Elaborate it with suitable examples?
Solution
Yes, the depletion of water resources is a major cause of social conflicts and disputes at various levels. As water becomes scarcer, competition over its sharing and control intensifies among different users and regions.
Nature of Conflicts:
These conflicts can manifest in several ways:
- Inter-State Disputes: The most prominent conflicts are between states over the sharing of river water. When a river flows through multiple states, disagreements arise over the construction of dams, diversion of water, and the allocation of water shares, especially during dry seasons. The chapter mentions that sharing and control of this scarce resource are becoming contested issues among states.
- Inter-regional and Community Conflicts: Within a state, conflicts can arise between different regions or communities. For example, urban areas with high water demand might draw water from surrounding rural areas, leading to shortages and resentment among the rural population. Similarly, conflicts can occur between industrial users and agricultural users who compete for the same limited water source.
- Social Upheaval: The text warns that if the demand for water continues to outstrip supplies, such a situation "will be detrimental to development, and can cause social upheaval and disruptions." This indicates that water scarcity can lead to widespread social unrest, protests, and tensions, particularly affecting the poor who have limited access to water.
The newspaper clipping in the chapter, titled "Rivers of conflict...but also of peace," highlights that water has been a major cause of tension and conflict within and among nations for centuries. While the text does not name specific disputes, real-world examples like the Kaveri river dispute between Karnataka and Tamil Nadu illustrate how depleting resources can fuel long-standing social and political conflicts.
Q3EXERCISES
(iii) What is watershed management? Do you think it can play an important role in sustainable development?
Solution
Watershed Management:
Watershed management refers to the efficient management and conservation of surface and groundwater resources within a watershed. It is a holistic approach that involves preventing soil runoff, and storing and recharging groundwater through methods like percolation tanks, recharge wells, and check dams. In a broader sense, it includes the conservation, regeneration, and judicious use of all natural resources like land, water, plants, and animals, along with human resources within the watershed. The primary goal is to create a balance between natural resources and society.
Role in Sustainable Development:
Watershed management plays a critical role in achieving sustainable development. It addresses the three core pillars of sustainability: environmental, economic, and social.
- Environmental Sustainability: By focusing on water conservation, groundwater recharge, and afforestation, watershed management helps in rejuvenating the local ecosystem. It prevents land degradation, improves water quality, and ensures the long-term availability of water resources.
- Economic Development: The success of watershed projects leads to increased water availability for irrigation, which boosts agricultural productivity and provides food security. This, in turn, enhances income levels and creates employment opportunities for the rural population. The case study of Ralegan Siddhi shows how the village transformed from poverty to a flourishing agricultural economy through watershed development.
- Social Equity: Watershed management programs are successful largely due to community participation. Projects like 'Haryali' and 'Neeru-Meeru' involve local people in planning and implementation. This empowers communities, promotes self-reliance, and ensures that the benefits of development are distributed equitably.
Therefore, by integrating water conservation with economic and social development, watershed management provides a viable framework for sustainable development, ensuring that present needs are met without compromising the ability of future generations to meet their own.
Q3EXERCISES
(i) Discuss the availability of water resources in the country and factors that determine its spatial distribution?
Solution
India has significant water resources, but their availability is limited and unevenly distributed.
Availability of Water Resources:
India receives about 4,000 cubic km of water from annual precipitation. However, the total available water from surface sources (rivers, lakes) and replenishable groundwater is estimated at 1,869 cubic km. Due to various constraints, only about 60 per cent of this, which is 1,122 cubic km, can be put to beneficial use. Surface water resources are primarily from the country's extensive network of rivers, with a mean annual flow of 1,869 cubic km, of which only 690 cubic km can be utilised. The total replenishable groundwater resource is about 432 cubic km.
Factors Determining Spatial Distribution:
The spatial distribution of water resources in India is highly uneven due to the following factors:
- Variation in Precipitation: India experiences high spatial and temporal variability in rainfall. The monsoon season accounts for most of the annual precipitation, but its intensity varies significantly across the country. Regions like the North-East receive heavy rainfall, while areas like Rajasthan and the Deccan plateau are rain-deficient.
- Size of Catchment Area: The flow of water in a river depends on the size of its catchment area or river basin. Large river basins like those of the Ganga, Brahmaputra, and Indus have huge catchment areas located in regions of high precipitation. Consequently, these river basins, which account for about one-third of the country's total area, hold about 60 per cent of the total surface water resources.