NCERT Solutions for Class 12 Geography India: People and Economy Chapter 9: Geographical Perspective on Selected Issues and Problems

Chapter at a glance

Exercise Questions

Question 1 (i)

Which one of the following rivers is highly polluted?
(a) Brahmaputra (b) Satluj (c) Yamuna (d) Godavari

Answer

The Yamuna, especially in its stretch through Delhi (between Delhi and Etawah), is one of the most polluted rivers in India, due to untreated sewage and industrial effluents.

3. Yamuna

Question 1 (ii)

Which one of the following diseases is caused by water pollution?
(a) Conjunctivitis (b) Diarrhoea (c) Respiratory infections (d) Bronchitis

Answer

Diarrhoea is a water-borne disease caused by contaminated water (others: cholera, typhoid, hepatitis, intestinal worms). Respiratory infections and bronchitis are linked to air pollution.

2. Diarrhoea

Question 1 (iii)

Which one of the following is the cause of acid rain?
(a) Water pollution (b) Land pollution (c) Noise pollution (d) Air pollution

Answer

Acid rain is caused by air pollution — oxides of sulphur and nitrogen released by burning fossil fuels combine with water vapour to form sulphuric and nitric acids that fall with rain.

4. Air pollution

Question 1 (iv)

Push and pull factors are responsible for–
(a) Migration (b) Land degradation (c) Slums (d) Air pollution

Answer

Push factors (poverty, unemployment, lack of facilities at origin) and pull factors (jobs, better facilities at destination) are responsible for migration.

1. Migration

Question 2 (i)

What is the difference between pollution and pollutants?

Answer

• Pollution is the process/condition of contamination of the environment — the release of substances and energy as waste products of human activities, which results in harmful changes in the natural environment (air, water, land).
• Pollutants are the substances or agents that cause pollution — e.g. smoke, sulphur dioxide, carbon monoxide, sewage, industrial effluents, pesticides, plastics, noise.

Pollution is the harmful contamination of the environment by wastes of human activities; pollutants are the substances or agents that cause it (e.g. smoke, SO₂, sewage, effluents, pesticides, plastics, noise).

Question 2 (ii)

Describe the major source of air pollution.

Answer

Air pollution is the addition of contaminants (dust, fumes, gas, fog, odour, smoke, vapour) to the air in substantial proportion and duration that may be harmful to living beings. Major sources: 1. Combustion of fossil fuels – coal, petroleum and diesel in thermal power plants, homes and industries. 2. Industries – industrial processes release oxides of sulphur and nitrogen, hydrocarbons, carbon dioxide, carbon monoxide, lead, asbestos. 3. Vehicles (transport) – exhaust fumes from cars, buses, trucks. 4. Mining, construction dust, burning of garbage and crop residues (stubble burning).

The major sources of air pollution are the combustion of fossil fuels (thermal power, homes), industrial processes releasing SO₂, NOₓ, hydrocarbons, CO and lead, vehicle exhausts, mining and construction dust, and burning of garbage and crop residues.

Question 2 (iii)

Mention major problems associated with urban waste disposal in India.

Answer

1. Huge quantity of solid waste (household, industrial, construction, hospital and e-waste) generated by growing urban populations.
2. Inadequate collection – in many cities, a large part of waste is not collected and is dumped on roads, open spaces and drains.
3. Lack of segregation of biodegradable and non-biodegradable waste.
4. Unscientific disposal – open dumping and burning in landfills, which pollutes air, soil and groundwater.
5. Health hazards – breeding of flies, mosquitoes and rats; spread of diseases (typhoid, diarrhoea, malaria, plague).
6. Blocked drains causing waterlogging and floods; foul smell; untreated sewage polluting rivers.
7. Lack of land for landfills; poor recycling.

Problems include huge amounts of waste, inadequate collection with waste dumped on roads and drains, lack of segregation, open dumping and burning that pollutes air, soil and water, health hazards from flies, mosquitoes and rats, blocked drains and floods, untreated sewage entering rivers, and shortage of landfill space and recycling.

Question 2 (iv)

What are the effects of air pollution on human health?

Answer

Air pollution causes various diseases related to the respiratory, nervous and circulatory systems: asthma, bronchitis, lung infections, pneumonia, lung cancer, heart diseases, eye and throat irritation, allergies and headaches. Lead affects the nervous system and children’s mental development. Smoke and smog reduce visibility and cause smoky fog (smog) over cities. It also causes acid rain.

Air pollution causes respiratory diseases (asthma, bronchitis, pneumonia, lung cancer), heart and circulatory problems, nervous disorders (e.g. from lead), eye and throat irritation and allergies, and creates smog over cities.

Question 3 (i)

Describe the nature of water pollution in India.

Answer

Water pollution – indiscriminate use of water by an increasing population and industrial expansion has led to considerable degradation of water quality. Surface water available from rivers, canals, lakes, etc. is never pure; it contains small amounts of suspended particles, organic and inorganic substances. When their concentration increases, water becomes polluted and unfit for use, and the self-purifying capacity of water is unable to purify it.

Sources: 1. Natural sources – erosion, landslides, decay and decomposition of plants and animals. 2. Human sources (main): - Industries – produce undesirable products, including industrial wastes, polluted wastewater, poisonous gases, chemical residues, heavy metals, dust and smoke; most industrial wastes are disposed off in flowing water or lakes, and poisonous elements reach reservoirs, rivers and other water bodies, destroying the bio-system. Major water-polluting industries are leather, pulp and paper, textiles and chemicals. - Urban sewage – untreated domestic sewage from cities and towns is discharged into rivers. - Agriculture – modern agriculture uses various kinds of inorganic fertilisers, pesticides and herbicides, which are washed down to the ground and water bodies; they also pollute groundwater through percolation (e.g. nitrate concentration in groundwater in Punjab, Haryana). - Cultural activities – pilgrimages, religious fairs, tourism, bathing, immersion of idols, dumping of ashes and dead bodies in rivers (Ganga) pollute water.

Polluted rivers: the Ganga (especially downstream of Kanpur, Varanasi, Patna) and the Yamuna (especially the Delhi–Etawah stretch, with sewage and industrial effluents from Delhi, Agra, Mathura) are among the most polluted rivers; other rivers like the Gomti, Damodar, Sabarmati and Mithi are also polluted.

Effects: water-borne diseases (diarrhoea, intestinal worms, hepatitis); death of aquatic life; reduced availability of clean water.

Measures: Namami Gange programme (cleaning the Ganga — sewage treatment, riverfront development, afforestation, public awareness), National River Conservation Plan, effluent treatment plants, laws against dumping.

Water pollution in India results from industrial effluents (leather, paper, textiles, chemicals), untreated urban sewage, agricultural fertilisers and pesticides that also contaminate groundwater, and cultural practices like bathing, idol immersion and dumping ashes. The Ganga and Yamuna (especially Delhi–Etawah) are among the most polluted rivers, leading to water-borne diseases and loss of aquatic life; programmes like Namami Gange aim to clean them.

Question 3 (ii)

Describe the problem of slums in India.

Answer

Slums are residential areas of the least choice, dilapidated houses, poor hygienic conditions and poor ventilation, lacking basic amenities like drinking water, light and toilet facilities. They arise because rural-to-urban migrants (pushed by poverty and pulled by urban jobs) cannot afford proper housing in cities and settle on vacant land, along railway tracks, drains and river banks.

Problems faced by slum dwellers: 1. Overcrowding – congested, narrow lanes; one-room houses for large families. 2. Poor housing – dilapidated, temporary structures of mud, tin and plastic, prone to fire. 3. Lack of basic amenities – no proper drinking water, electricity, sewerage, toilets; open defecation; garbage heaps. 4. Health problems – unhygienic conditions, malnutrition and pollution cause diseases (diarrhoea, tuberculosis, malaria, skin diseases); poor access to health care. 5. Poverty and low incomes – slum dwellers work in the informal sector as low-paid labourers, domestic workers, hawkers, rickshaw pullers; insecure employment. 6. Social problems – illiteracy, child labour, drug abuse, alcoholism, crime, violence, social exclusion and discrimination. 7. Insecurity of tenure – threat of eviction and demolition.

Example: Dharavi in Mumbai is one of the largest slums in Asia; it lacks basic amenities yet houses numerous small industries (leather, pottery, recycling).

Measures: in-situ slum redevelopment, affordable housing (PM Awas Yojana – Urban), provision of basic services, skill development, and better rural development to reduce distress migration.

Slums are overcrowded settlements of dilapidated houses with poor sanitation and ventilation, formed mainly by poor rural migrants who cannot afford urban housing. Residents face overcrowding, unsafe housing, lack of drinking water, toilets, drainage and electricity, diseases, low and insecure informal incomes, illiteracy, child labour, crime and fear of eviction (e.g. Dharavi in Mumbai). Remedies include slum redevelopment, affordable housing, basic services and rural development.

Question 3 (iii)

Suggest measures for reduction of land degradation.

Answer

Land degradation is the reduction in the productive capacity of land, caused by natural processes (soil erosion, floods, droughts) and human activities (deforestation, overgrazing, faulty irrigation, mining, overuse of chemicals, industrial and urban waste).

Measures: 1. Afforestation and checking deforestation; planting trees on wastelands, along rivers and in catchments; shelterbelts in deserts to check wind erosion. 2. Controlled grazing – checking overgrazing, rotational grazing, developing pastures and fodder. 3. Soil conservation – contour ploughing, terrace farming on slopes, strip cropping, building check dams, bunds and gully plugs to control water erosion and ravines. 4. Watershed management – conservation of water, soil and vegetation with people’s participation (e.g. the Jhabua district case study in Madhya Pradesh — the Bhils revitalised large parts of common property resources through watershed management, planting and protecting pastures; Haryali, Neeru-Meeru). 5. Proper irrigation and drainage – avoiding over-irrigation, providing drainage to prevent waterlogging and salinity; use of gypsum to reclaim alkaline soils. 6. Judicious use of fertilisers and pesticides; promoting organic farming, crop rotation, leguminous crops and green manure. 7. Reclamation of mined areas – refilling, levelling and afforestation after mining. 8. Proper disposal of industrial and urban waste; treating effluents. 9. Stabilisation of sand dunes in deserts. 10. Awareness and community participation; laws and policies for land use planning.

Measures include afforestation and shelterbelts, controlled grazing and pasture development, soil conservation through contour ploughing, terracing, strip cropping, check dams and gully plugging, watershed management with community participation (e.g. Jhabua), proper irrigation and drainage to prevent waterlogging and salinity, judicious use of chemicals and organic farming, reclamation of mined land, safe disposal of wastes, stabilisation of sand dunes, and awareness.

Topic checklist

• ☒ Pollution and pollutants; air and water pollution (Q 1 (i)–(iii), 2 (i), 2 (ii), 2 (iv), 3 (i))
• ☒ Urban waste, migration and slums (Q 1 (iv), 2 (iii), 3 (ii))
• ☒ Land degradation (Q 3 (iii))

Total questions answered: 11 of 11