Class 12 Geography Chapter 12 Geographical Perspective on Selected Issues and Problems Question Answer Part 2 NCERT Textbook Questions Solved
Chapter 12 Geographical Perspective on Selected Issues and Problems Part B Geography- India People and Economy NCERT Solutions for Class 12 Geography
CBSE Class 12 Geography Chapter 12 Geographical Perspective on Selected Issues and Problems Question Answer Part 2
1. Choose the right answers of the following from the given options:
(i) Which one of the following river is highly polluted?
Ans. (3) Yamuna
(ii) Which one of the following diseases is caused by water pollution?
- Respiratory infections
Ans. (2) Diarrhoea
(iii) Which one of the following is the cause of acid rain?
- Water pollution
- Land pollution
- Noise pollution
- Air pollution
Ans. (4) Air Pollution
(iv) Push and pull factors are responsible for –
- Land degradation
- 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:
- Urban areas are generally marked by overcrowding, congestion, inadequate facilities to support the fast growing population and consequent poor sanitary conditions and foul air.
- Environmental pollution by solid wastes has now got significance because of enormous growth in the quantity of wastes generated from various sources.
- 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:
- Natural sources—Water is polluted by natural agents such as erosion,landslides, decay and decomposition of plants and animals.
- 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:
- It is a source of various water-borne diseases like diarrohea, intestinal worms and hepatitis.
- It is a great threat to marine ecosystem.
- The potable safe drinking water is declining.
- Groundwater table is also on decline.
- 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.
- 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.
NCERT Solutions Class 12th Geography Question Answer Free Download
CBSE Class 12th Geography Question Answer: Fundamentals of Human Geography
NCERT Books Solutions for Class 12 Geography Question and Answer: Fundamentals of Human Geography
- Chapter 1 Human Geography (Nature and Scope)
- Chapter 2 The World Population (Distribution, Density, and Growth)
- Chapter 3 Population Composition
- Chapter 4 Human Development
- Chapter 5 Primary Activities
- Chapter 6 Secondary Activities
- Chapter 7 Tertiary and Quaternary Activities
- Chapter 8 Transport and Communication
- Chapter 9 International Trade
- Chapter 10 Human Settlements
CBSE Class 12 Geography Question Answer: India People and Economy
NCERT Solutions for Class 12 Geography: India People and Economy
- Chapter 1 Population: Distribution, Density, Growth, and Composition
- Chapter 2 Migration: Types, Causes, and Consequences
- Chapter 3 Human Development
- Chapter 4 Human Settlements
- Chapter 5 Land Resources and Agriculture
- Chapter 6 Water Resources
- Chapter 7 Mineral and Energy Resources
- Chapter 8 Manufacturing Industries
- Chapter 9 Planning and Sustainable Development in the Indian Context
- Chapter 10 Transport And Communication
- Chapter 11 International Trade
- Chapter 12 Geographical Perspective on Selected Issues and Problems
Geographical Perspective on Selected Issues and Problems Important Extra Questions Very Short Answer Type
In which town, do vehicles emit most carbon-monoxide ?
What is the volume of polluted water flowing in Ganga river daily ?
87.3 crore litre.
How many leather tanneries are located along the Ganga hanks ?
Name two sources of Air Pollution.
Volcanoes and industries.
Name a gas which depletes Ozone gas.
Classify pollution into three main types.
Pollution can be classified into three categories on the basis of medium of transportation of the pollutants:
- Air pollution
- Water pollution
- Land pollution.
What is the total number of two- wheelers in India.
117 crores (2010-11).
What is Smog ?
Smog is smoky fog in urban industrial cities when carbondioxide freezes over smoke.
Name the Anthropogenic sources of pollution.
Industrial sources, urban source, agricultural sources, cultural sources.
Name the two polluted rivers of India.
Ganga and Yamuna.
Name the cultural sources of pollution.
Pilgrimages, religious fairs, tourism.
How much area is under land erosion in India ?
13 crore hectares.
Which areas have become alkaline and saline and why ?
Northern India due to over-irrigation.
Name the ill-effects of use of chemical fertilisers.
It destroys the micro-organisms of the soils.
What is the cause of acid-rain? (C.B.S.E. 2014)
Sulphur emitted from factories.
How can urban waste become a resource?
When it is used for generating energy and compost.
Which type of pollution causes various diseases related to the respiratory system? (Sample Paper 1)
Name the two cities of U.P. that are mainly responsible for pollutions the river Ganga. (C.B.S.E. 2011)
(Sample Paper 2)
Kanpur and Varanasi.
Mention any two cultural activities responsible for water pollution in India. (C.B.S.E. 2009) (Sample Paper 2017-18)
(i) Religious fairs
Which is the main source of water borne diseases in India? Name one water borne disease. (C.B.S.E. 2009)
Contaminated water is the main source of water borne diseases. Hepatitis is a water borne disease.
Name the two states of India which have less than five percent of population below poverty line.
Goa (4.40% poverty) and Andaman and Nicobar Islands (1% poverty) are the two states having less than 5% population below poverty line.
Why Swachh Bharat Mission is launched ?
This is apart of the urban renewals mission by the government of India. SBM is launched to improve that quality of life in urban slums.
Geographical Perspective on Selected Issues and Problems Important Extra Questions Short Answer Type
Mention three criterias used for identi¬fying pollution.
(i) Disposal of Human wastes.
(ii) Damages caused by disposal wastes.
(iii) Effect of damage caused.
What is the difference between pollution and pollutants ?
Pollution means degradation of air, land, water. It deteriorates our resources. Pollutants are matter causing degradation and pollution of ecosystem.
Give two examples of River pollution.
Pollution of Rivers. With rapid urbanisation and industrialisation, huge quantities of waste water enter rivers. About 873 million litres per day (mid) of waste water drained into the Ganga before the Ganga Action Plan was initiated. The Sabarmati, a small river, alone receives 998 mid of dirty water from the city of Ahmedabad.
Explain any five objectives of ‘Namami Gange Programme’. (Outside Delhi 2019)
Ganga river has national importance but this river needs cleaning by effectively controlling the pollution. The water of this river is polluted ‘Namami Gange Programme’ has launched by union government.
Objectives of Namami Gange Programme are:
- Motive to develop sewerage treatment system in towns.
- Objective of creating awarness in public to avoid adding pollutants in to the water of the river. People because of their own rituals do so.
- Objective of development of Ganga Grams in the areas of Uttarakhand, U.P., Jharkhand, Bihar and W.B.
- Industrial pollution from towns also a serious problem for the river. So monitoring of industrial effluents is also a major objective of the programme.
- Domestic wastes from urban centres also a serious problem so cleaning of the surface of the river is also a good objective.
Mention any two source of land pollution in India. (C.B.S.E. 2013)
(i) Human and animal excreta.
(ii) Use of pesticides and fertilisers.
Describe any three problems of slums in India. (C.B.S.E. 2014)
(i) There is a lack of basic amenities like toilet, safe drinking water, electricity, etc., in slums.
(ii) People are prone to diseases and illness as they are malnourished.
(iii) Poverty makes people vulnerable to drug abuse, alcoholism, crime and exclusion from society.
Describe the effects of air pollution. (C.B.S.E. 2011)
How is air pollution harmful ?
Explain any three different cause’s of air pollution. (Outside Delhi 2019)
“Air pollution is very harmful to flora, fauna and property. Explain any three values which can help in maintaining pollution free air to some extent. (C.B.S.E. Delhi 2017)
Effects of air pollution. The air pollution modifies weather and climate, effects human health and biotic community.
(1) Chlorofluorocarbons (CFCs) cause depletion of ozone layer which enable ultraviolet rays of the sun to reach the earth and increase atmospheric temperature.
(2) Increased concentration of carbon dioxide and other gases in the atmosphere causes greenhouse effect raising the atmosphere temperature.
(3) Smoky fog over cities called as urban smog is caused by these gases. It proves very harmful to human health.
(4) Air pollution can also cause acid rains.
(5) Rainwater analysis of urban environment has indicated that pH value of the first rain after summer is always lower than the subsequent rains. Studies conducted by NEERI show that the minimum pH of 4.5 was in Kochi, while the average pH of all rains at all the urban agglomerations ranged from 6.2 to 7.6.
Name the Industrial wastes causing water pollution.
Though water pollutants are also created from natural sources (erosion, landslides, decay and decomposition of plants and animals, etc.) pollutants from anthropogenic sources are the real causes of concern. They include industrial sources, urban source, agricultural source, cultural source, etc.
Industries produce several undesirable products including industrial wastes, polluted waste water, poisonous gases, chemical residuals, numerous heavy metals, dust, smoke, etc. Most of the industrial wastes are disposed off in running water. Consequently, poisonous elements reach the reservoirs, rivers and other water bodies which destroy the biosystem of these waters. Major water polluting industries are leather, pulp and paper, textiles and chemicals.
How is air pollution harmful ? Explain any three different causes of air pollution.
Air pollution is harmful. Air pollution results into the spread of diseases related to lungs, skin and throat etc. Air pollution also causes acid rain which damages human health. The ozone layer is depleted by the chlorofluorocarbon and great shrinkage in the glacier.
Causes of air pollution:
(i) Natural Resources: Such as volcanic eruption, dust, strom, fires etc.
(ii) Factories: Factories cause smoke, ash.
(iii) Automobiles: Automobilies release carbon monoxide & lead in the atmosphere. Transport and farming are the main actions that have been directly linked to emissions. Forest fires and the burning of living, or recently living organisms, represent a further major sources of emission.
Name the diseases caused by air and water pollution. (C.B.S.E. 2014)
Air pollution causes diseases of lungs, heart, nervous and circulatory systems. A study conducted in the ambient air of Kolkata (in 1994) concluded that three out of every ten persons in the city suffered from some kind of respiratory diseases that cough, bronchitis and allergic-rhinitis which were associated with concentrations of suspended particulate matter.
The diseases commonly caused due to contaminated water are diarrhoea, trachoma, intestinal worms, hepatitis, etc. Recent World Bank and World Health Organisation data shows that about one-fourth of the communicable diseases in India are water-borne.
Compare the water pollution in Ganga and Yamuna Rivers.
|Ganga River||Yamuna River|
|1. Polluted stretches|
2. Nature of pollution
|(a) Downstream of Kanpur.|
(b) Downstream of Varanasi.
(c) Farrakka barrage to Allahabad.
1. Industrial pollution from towns like Kanpur.
2. Domestic wastes from urban centres.
3. Dumping of carcasses in the river.
|(a) Delhi to confluence with Chambal.|
(b) Mathura and Agra.
1. Extraction of water by Haryana and Uttar Pradesh for irrigation.
2. Agricultural run off resulting in high levels of micro-pollutants in the Yamuna.
3. Domestic and indus- trial waste of Delhi flowing into the river.
Write a note on Land Pollution.(C.B.S.E. 2011)
Land Pollution. Land pollution encompasses the degradation and pollution of soil and vegetative cover. Deterioration in the quality of soil occurs because of
- soil erosion
- reduction in plant nutrients
- decline in soil micro-organisms
- lack of moisture
- concentration of various harmful elements, etc.
Erosion is caused by natural and human factors. Deforestation, overgrazing and improper use of land also accelerates soil erosion. It is estimated that 130 million hectares of land is affected by erosion problems in the country. Shifting agriculture alone has affected about 30 million hectares.
Besides erosion, salinisation and flooding caused due to construction of dams, reservoirs, canals and tanks in geologically unsuitable areas, excessive use of canal irrigation and diversion of floodwater in areas of impervious rocks also reduce the potentiality of land. Because of over-irrigation, saline and alkaline areas have increased in the northern plains of the country.
Irrigation also changes the structure of the soil. Besides, use of chemical fertilisers, pesticides, insecticides and herbicides degrade the soil by destroying their natural- physical, chemical and biological properties. Chemical fertilisers destroy micro-organisms of the soil, which are agents of nitrogen conversion in the soil.
They increase sterility and reduce water-holding capacity of soil. They also leave their traces in crops, which act as slow poison for human beings. Similarly, organic phosphate compounds used to kill insects can stay for longer time in soils destroying micro-organism.
Geographical Perspective on Selected Issues and Problems Important Extra Questions Long Answer Type
Describe urbanisation in India and discuss its problems.
Urbanisation. Many Geographers have defined urbanisation.
- According to Griffith Taylor: Urbanisation is a shift of people from village to city.
- According to G.T. Trewartha: The urbanisation process denotes an increase in the fraction of a population which is urban.
According to changing Political, Social and Economic conditions, the human settlements have been developing. Rural settlements were changed to urban settlements. Therefore urbanisation is a process in which rural settlement, change to urban settlements. According to E.E. Bergel, “The process of change of villages to towns is known as urbanisation. ”
Nature and Trends of Urbanisation in India
In India, urbanisation has not developed on a large scale. The size of urban population is large, India has the second largest urban population in the world, but the percentage of urban population is only 31.6%.
It is small as compared to urban population of 82.6% in USA, 91.7% in Japan, 74% in Russia, 89.3% in Australia and 86.3% in New Zealand. China has 51.8% urban population. During the last 100 years, the urban population is increasing in India. It has increased from 11% to 31.16% in 2011. The total urban population was 2-6 crores in 1901. It has increased 11 times now.
|Year||Total Urban Population (million)||% of Total||Increase %|
Problems of Slums and Urban waste : Many problems have arisen due to increasing population and urbanisation. The problems of slums and disposal of urban waste are the two main problems.
Slums: There is a shortage of space in towns. The increasing population creates housing problems. Multi-storeyed buildings are being constructed to solve it. Generally, push and pull factors force the people to migrate to towns.
These people move in search of employment. In towns, the housing facility is costlier. The people construct huts on the vacant land outside the towns. There is dense population in such slums. There is no facility for water-drainage and disposal of urban waste. People’s standard of living is very low. The administration has taken many steps to provide facilities to these areas, yet these slums suffer from many diseases.
According to 2001 census, data was collected regarding slums. This population is known as the slum population. About 4 crore 3 lakh people live in slums. This covers a population of 22.6% of towns, with the result 1/4 of urban population lives in slums. The maximum number of slums are found in Maharashtra and have a population of 1,06,40,000.
The maximum slum population in towns is found in Mumbai with a population of 48.8 per cent. Patna has only 0.25 percent slum population. Meghalaya has the highest percentage (41.33%) and Kerala has the lowest percentage (1.81%) of slum population.
Disposal of urban waste : Another problem in urban areas is the domestic sewage. This urban waste leads to water pollution. The urban waste, the animal waste and the industrial waste material is deposited in heaps over land due to which the land becomes unsuitable for other uses. This waste creates many health problems. The urban waste thrown in rivers and streams cause water pollution.
The waters of river Ganga and Yamuna have been polluted in this way. The towns located along the banks of these rivers use their water as drinking water. The polluted water affects animals living in rivers and spreads many diseases like Hepatitus, Typhoid, Dysentery, etc. which affects human health.
Write a note on Environmental pollution in India.
Environment: Environment is the sum total of a set of surroundings that affect the development and life of organisms. It includes natural as well as cultural environment.
Environmental Pollution : Environmental pollution has become a serious problem for mankind. It is threatening the existence of mankind. The composition of air is being altered by undesirable chemical, physical and biological elements. It is known as air pollution.
Atmospheric pollution is as old as civilisation. The use of fire caused gases, smoke, ash. With the development of Industrialisation, the natural composition of the earth atmosphere is gradually degrading. It has damaged the environment. The atmospheric pollution has endangered the existing and future generations.
Pollutants : The common pollutants found in air are as follows:
- Deposited matter like Soot, Smoke, tandust.
- Gases like sulphur, Carbon-monoxide, Nitrogen oxide, Ammonia, Fluorine, etc.
- Chemical Compounds : Like arenes, Phosgenes, detergents.
- Metals like lead, Iron, zinc, mercury.
- Radio-active Substances.
- Noise and heat.
Atmospheric Pollution. Atmosphere is of fundamental importance for our existence. Due to industrial revolution, the atmospheric pollution is increasing gradually. The effect of atmospheric pollution is not local but regional. The whole of atmosphere is affected. It has harmed ultra-violet shielding ozone layer. The addition of heat-trapping green house gases will cause a disaster.
Air-Pollution by Natural Agents : The volcanic eruptions, forest fires, natural decay of organic and in organic matter is causing air pollution. These cause smoke, ash, gases in atmosphere. These, reduce visibility. Smoke is injurious to health. Acid rain has changed the composition of air and water.
Human activities : The burning of fuels and chemicals is increasing the amount of carbon dioxide in atmosphere. It has increased by 25%. With the result, the average temperature of the earth is increasing. It has increased by 0.3°C to 0.7°C during the last century. Deforestation has also lead to increase in carbon dioxide. The increasing use of fuels in vehicles has increased the amount of sulphur dioxide, carbon monoxide and has created many respiratory diseases.
Atmosphere is of fundamental importance for human health. Most of the countries of the world have enacted laws to check air pollution. Only a healthy nation can utilize its natural resources.
Water pollution : Water is another indispensable source of our life. Pollution of water has caused far- reaching implications. It is a serious problem in metropolitans like Delhi, Kolkata and Mumbai. It not only affects the water of rivers, tanks and lakes; but also ocean water. The following factors affect water pollution:
- Domestic sewage
- Industrial wastes
- Agricultural activities
- Thermal pollution
- Marine pollution.
Land Pollution: Land is one of the most important components of life support system. Land is degrading due to over use from centuries. Depletion of land is caused by :
- Soil erosion
Soil erosion is active on steep slopes and areas devoid of vegetation. Torrential rainfall also washes away fertile layer of soil. Ravines or gullies are caused. Deforestation, over grazing has also led to soil erosion. The effect of soil erosion is a serious problem in agricultural countries.
The accumulation of pollutants on land makes it unsuitable for other uses. The impact of soil erosion on ecological system is visible in Siwalik hills where the harm has been done by chos.
Describe the major problems I associated with urban water disposal in India. (C.B.S.E. 2011)
Urban Waste Disposal Problems. The environmental problems of cities include water, air and noise pollution and disposal of toxic and hazardous wastes.
Problems. Lack of sewers or other means to dispose off human excretes safely and the inadequacy of garbage collection services adds to water pollution because many of the uncollected wastes are washed into streams. The dumping of industrial waste into rivers is a major cause of industrial waste into rivers is a major cause of water pollution. River pollution from city-based industries and untreated sewage leads to serious health problems downstream.
Increase in urban wastes.
Solid waste generation continues to increase in both absolute and per capita terms in cities. It is estimated that per capita waste generation increased from 375 gm/day to 490 gm/day during 1971-1997 in urban areas of the country. This increase along with the population increase has tremendously swollen up the figuers of total waste generation quantum. The amount of total wastes has increased from 14.9 Tonnes per day to 48. Tonnes per day.
III effects of urban waste : At the same time, the composition of solid waste changes from biodegradable organic material to plastic and other synethetic materials, which take much longer time to decompose. When this solid waste is not collected and disposed off efficiently and effectively, it attracts rodents and flies which spread diseases. It also pollutes and degrades land and water resources.
Table. India: Composition of Solid Wastes from Cities (in Percentage)
|Year/Components||Paper||Plastics||Metals||Glass||Rags||Ash and fine earth||Total|
|1971-73 (40 cities)||4,14||0.69||0.60||0.40||3.83||49.20||41.24|
|1995 (23 cities)||5.78||3.90||1.10||2.10||3.50||40.30||41.80|
It is evident from the above Table that shares of plastics, glass and metals increased remarkably through time. Plastics recorded five-fold jump within twenty years. Most of these do not have a good recycling value and hence are disposed off by municipalities as part of the kitchen waste.
Harmful for Health.
Inability to collect solid waste is a serious problem. In metropolitan cities like Mumbai, Kolkata, Chennai, Bangalore, etc. about 90 per cent of the solid waste is collected. But in most of the cities and towns about 30 to 50 per cent of the waste generated are left uncollected which accumulate on streets, in open spaces between houses and in wasteland, contributing to serious health hazards.
It is remarkable that both formal and informal sectors are involved in collection of solid waste, yet the problem of urban waste disposal remains unsolved. These wastes should be treated as Resource and utilized for generating energy and comfort.
Effect on ground water. About 90 percent of the municipal water collected by the civic authorities is dumped in low-lying areas outside the city/town limit, without any provision for treatment. As a result, heavy metals find their way to the underground water rendering it unfit for drinking. Untreated wastes ferment slowly and release noxious biogas to the atmosphere, including methane (65 to 75 per cent) which is a green house gas and which has a global warming potential 34 times more than carbon dioxide.
Explain soil erosion, salinisation and water logging problems.
1. Irrigation. Because of our irrigation, saline areas increased in northern planes of country. Irrigation also changes the structure of the soil.
2. Use of chemicals. Besides, use of chemical fertilisers, pesticides, insecticides and herbicides degrades the soil by destroying their natural, physical, chemical and biological properties.
3. Use of fertilisers. Chemical fertilisers destroy micro-organisms of the soil, which are agents of nitrogen conversion in the soil. They increase sterility and reduce water-holding capacity of the soil. They also leave their traces in crops, which act as slow poison for human beings.
4. Use of pesticides. Similarly, organic phosphate compounds used to kill insects can stay for longer time in soils destroying micro-organisms.
5. Industrial wastes. Improper disposal of industrial and urban wastes, and irrigation of agricultural fields with polluted urban sewage water near urban and industrial areas degrade the soil. The toxic chemical substances of industrial effluents and urban sew’age enter the soil mostly in their neighbourhoods and pollute them.
6. Pollutants emitted by chimneys. Besides gaseous and solid pollutants emitted by the factory chimneys are transported by winds. These pollutants containing toxic substances, are deposited on soils and pollute them.
7. Acid Rain. Sulphur emitted from factories cause acid rains which increases the acidity of the soils. Pollutant from cement factories like klins, coal mining and transport vehicles, thermal power plants, etc., also pollute the soils on a large scale.
Describe the air pollution caused by automobiles. Give examples for four metro- politons.
The vehicles which use leaded fuel, account for about 95% of air borne lead pollution. The growth of number of motor vehicles in the last three decades has been almost 32 times. In 1997-98, there were 0.53 million buses, 2.53 million trucks, 28.24 million two- wheelers, 1.34 million auto rickshaws and 5.05 million cars, jeep and taxis.
Urban air quality has generally deteriorated throughout India. The reasons are absence of pollution abatement and rising number of motor vehicles that use leaded fuels. The annual mean concentration trends for the National Environmental Engineering Research Institute (NEERI) for some cities observed various atmospheric pollutants. From figures,
(1) it is clear that nitrogen dioxide concentraton trend is stabilising for Mumbai, Kolkata and Chennai
(2) sulphur dioxide concentrations are decreasing in Delhi but still increasing in Mumbai and Kolkata.
(3) Suspended Particulate Matter (SPM) concentrations have somewhat increased in all these cities.
Table. India: Estimated Vehicular Emission Load in certain Metropolitan Cities
(Vehicular Pollution Load tonne per day)
Geographical Perspective on Selected Issues and Problems Important Extra Questions HOTS
‘Land Degradation is caused by human made processes are more harmful than natural processes in India.’ Analyse the statement with suitable examples. (C.B.S.E. 2009)
Land degration caused by man-made processes amounts to 5.58% of the total rate of degradation. It is more than land degraded by natural sources (2.4%). Wastelands are formed due to shifting cultivation, planation crops, degraded forests and pastures, mining and industrial wastelands.
Why is the ‘Urban Waste Disposal’ a serious problem in India? Explain any three reasons. (Delhi 2019) (C.B.S.E. 2014)
Urban waste disposal is a serious problem in India-
- Solid waste cause health hazard and spread diseases like Typhoid, Diphtheria, Diarrhoea, Malaria, and Cholera.
- The dumping of industrial waste into rivers leads to water pollution.
- Untreated wastes ferment slowly and release toxic gases into the atmosphere including Methane.
Explain the reasons for the coming up of slums in developing countries like India with suitable examples.
(Sample Paper 2018-19)
Slums are clusters of shanty structures. These are inhabited by those people who are forced to migrate from the rural areas to these urban centres in search of livelihood but are not able to afford proper housing due to high rents. They occupy environmentally incompatible and degraded areas. Developing countries like India face this problem at a large scale. For e.g., Dharavi, Asia is largest slum in a striking example of the same.