Chapter 12 Geographical Perspective on Selected Issues and Problems Part B Geography- India People and Economy NCERT Solutions for Class 12 Geography

NCERT Solutions for Class 12 Geography Part B – India People and Economy Chapter 12 Geographical Perspective on Selected Issues and Problems – Free PDF download

CBSE Class 12 Geography
NCERT Solutions
Part B – India People and Economy
Chapter 12 Geographical Perspective on Selected Issues and Problems

1. Choose the right answers of the following from the given options:

(i) Which one of the following river is highly polluted?

1. Brahmaputra
2. Satluj
3. Yamuna
4. Godavari

Ans. (3) Yamuna

(ii) Which one of the following diseases is caused by water pollution?

1. Conjunctivitis
2. Diarrhoea
3. Respiratory infections
4. Bronchitis

Ans. (2) Diarrhoea

(iii) Which one of the following is the cause of acid rain?

1. Water pollution
2. Land pollution
3. Noise pollution
4. Air pollution

Ans. (4) Air Pollution

(iv) Push and pull factors are responsible for –

1. Migration
2. Land degradation
3. Slums
4. Air pollution

Ans. (1) Migration

2. Answer the following question in about 30 words:

(i) What is the difference between pollution and pollutants?

Ans. Pollution: Contamination of air and water or environment due to increase in sound or deterioration of quality of land leading to a fall in its quality and purity is called pollution.

Pollutants: Those elements of products are called pollutants which deteriorate the quality of land, air or water on getting mixed with it. Some examples of pollutants are radioactive elements, carbon monoxide, solid waste, acids, etc.

(ii) Describe the major sources of air pollution.

Ans. Air pollution is taken as addition of contaminants like dust, fumes, gas, fog, odour, smoke or vapour to the air in substantial proportion and duration that may be harmful to flora and fauna and to property. Combustion of fossil fuels,burning wood and other fuels for heating and cooking,agricultural burning, land clearing, natural sources including volcanoes, forest fires and dust storm s, mining and industries are the main sources of air pollution.

(iii) Mention major problems associated with urban waste disposal in India.

Ans. Major problems associated with waste disposal in India are as follows:

1. Urban areas are generally marked by overcrowding, congestion, inadequate facilities to support the fast growing population and consequent poor sanitary conditions and foul air.
2. Environmental pollution by solid wastes has now got significance because of enormous growth in the quantity of wastes generated from various sources.
3. The huge turn out of ashes and debris from industries, thermal power houses and building constructions or demolitions have posed problems of serious consequences. Solid wastes cause health hazard through creation of obnoxious smell, and harbouring of flies and rodents, which act as carriers of diseases like typhoid, diphtheria, diarrhoea, malaria and cholera, etc.

(iv) What are the effects of air pollution on human health?

Ans. Air pollution causes various diseases related to respiratory, nervous and circulatory systems. Smoky fog over cities called as urban smog is caused by atmospheric pollution. Air pollution can also cause acid rains. pH value of the first rain after summer is always lower than the subsequent rains.

3. Answer the following question in about 150 words:

(i) Describe the nature of water pollution in India.

Ans. Water pollution: Degradation of the quality of water due to indiscriminate use of water is called water pollution. The water becomes unfit for use because of high concentration of suspended particles,organic and inorganic substances. In such a situation, the self-purifying capacity of water is unable to purify the water.

Sources of water pollution:

1. Natural sources—Water is polluted by natural agents such as erosion,landslides, decay and decomposition of plants and animals.
2. Human sources—
   • Industrial activities: Industries produce undesirable products, polluted waste, water, poisonous gases, chemical residues, heavy metals, dust, smoke. Most of the industries dispose off in running water or lakes. Consequently, the poisonous wastes are been released out which affect the biotic life. Industries like leather, pulp, paper, textiles and chemicals pollute the environment.
   • Agricultural activities: The use of fertilisers, pesticides, herbicides cause water to the rivers, tanks, lakes and underground water also gets contained. The fertilisers increase the nitrate content of surface water.
   • Cultural activities: Such as pilgrimage, religious fairs, tourism cause water pollution.
   • Urban activities: The improper sewage disposal and surface run-off causes water pollution.

Effects of water pollution:

1. It is a source of various water-borne diseases like diarrohea, intestinal worms and hepatitis.
2. It is a great threat to marine ecosystem.
3. The potable safe drinking water is declining.
4. Groundwater table is also on decline.
5. The accumulation of the deposits in the river channels would lead to the rise in
   the level of water in the rivers causing floods and at the same time, rivers may
   change their courses.
6. Pollution disrupts the natural food chain.

(ii) Describe the problems of slums in India.

Ans. The rapid growth of urbanisation and industrialisation results in the growth of slums. Slums are areas of the least choice, dilapidated houses, poor hygienic conditions, poor ventilation and lack of basic amenities like water, light and toilet facilities, The slum people belong to the lower income group. They can’t afford permanent houses. That is why they occupy any vacant land available in the city and build their huts. The number of slums are increasing day-by-day. Slum areas are overcrowded. Most of the slum dwellers work in low paid, high risk-prone, unorganised sectors of the urban economy. They are undernourished, prone to diseases and can’t afford to give proper education to their children. Due to miserable financial condition, their children do not go to schools and get trapped in the activities of drug, alcoholism, crime, etc.

(iii) Suggest measures for reduction of land degradation.

Ans. The pressure on agricultural land increases not only due to the limited availability
but also by deterioration of quality of agricultural land. Soil erosion, water logging,
salinisation and alkalinisation of land lead to land degradation.

The important measures for reduction of land degradation are-

1. Strip farming: It is practice in which cultivated crops are down in alternative strips to prevent water movement.

2. Crop rotation: lt is one of the agricultural practice in which different crops are grown in same area following a rotation system which helps in replenishment of the soil.

3. Ridge and Furrow Formation: Soil erosion is one of the factor s responsible for land degradation. It can be prevented by formation of ridge and furrow during irrigation which lessens run off.

4. Construction of Dams: This usually checks or reduces the velocity of run off so that soil support vegetation.

5.Contour Farming: This type of farming is usually practised across the hillside and is useful in collecting and diverting the runoff to avoid erosion.