Class 12 Geography Notes Chapter 12 (Geographical perspective on selected issues and problems) – India - People and Economy Book
Detailed Notes with MCQs of Chapter 12, 'Geographical Perspective on Selected Issues and Problems,' from your 'India - People and Economy' textbook. This chapter is crucial as it deals with contemporary environmental and social challenges India faces, viewed through a geographical lens. Understanding these issues is vital, not just for your exams, but also as informed citizens.
Chapter 12: Geographical Perspective on Selected Issues and Problems - Detailed Notes
1. Introduction: Environmental Concerns
- Development has brought economic growth but also led to significant environmental degradation and socio-economic problems like pollution, resource depletion, urban congestion, and health issues.
- Geography helps understand the spatial patterns of these problems, their causes, consequences, and potential solutions by studying human-environment interactions.
2. Environmental Pollution
- Definition: Release of substances or energy into the environment resulting from human activities, which have undesirable effects on living organisms and the environment.
- Classification based on Medium:
- Water Pollution
- Air Pollution
- Land Pollution
- Noise Pollution
3. Water Pollution
- Definition: Deterioration of water quality due to the addition of unwanted substances, making it unfit for desired use.
- Sources:
- Natural: Erosion, landslides, decay of organic matter, etc. (less significant in overall pollution load).
- Human Activities (Major Concern):
- Industrial Waste: Effluents containing heavy metals (lead, mercury, cadmium), chemicals, toxins, acids, alkalis, dyes, oils, etc. Industries like leather, pulp & paper, textiles, chemicals are major polluters.
- Agricultural Runoff: Fertilizers (nitrates, phosphates leading to eutrophication), pesticides, herbicides washed into water bodies.
- Urban Sources: Domestic sewage (largest source by volume), solid waste dumping, runoff from streets carrying various pollutants.
- Cultural Activities: Immersion of idols, disposal of puja materials, mass bathing, disposal of ashes/dead bodies in rivers.
- Thermal Pollution: Discharge of hot water from thermal power plants and industries, reducing dissolved oxygen.
- Oil Spills: From ships and offshore drilling.
- Major Polluted Rivers: Ganga and Yamuna are the most polluted rivers in India, primarily due to untreated sewage, industrial effluents, and agricultural runoff. Other rivers like Sabarmati, Gomti, Kali, Adyar, Cooum, Vaigai also face severe pollution.
- Impacts:
- Human Health: Spread of water-borne diseases like diarrhoea, cholera, typhoid, jaundice, intestinal worms, hepatitis.
- Aquatic Life: Kills fish and other organisms, disrupts ecosystems, causes eutrophication (excessive nutrient enrichment leading to algal blooms and oxygen depletion).
- Groundwater Contamination: Seepage of pollutants (nitrates, fluorides, arsenic, heavy metals) from surface sources, landfills, and agricultural fields contaminates groundwater, making it unfit for drinking. Fluoride and arsenic contamination are serious problems in parts of Rajasthan, Bihar, West Bengal, etc.
- Government Initiatives: Namami Gange Programme aims at abatement of pollution, conservation, and rejuvenation of the Ganga river.
4. Air Pollution
- Definition: Presence of undesirable substances (gases, particulate matter) in the atmosphere in concentrations harmful to human health, vegetation, animals, and materials.
- Sources:
- Combustion of Fossil Fuels: Major source. Includes vehicles, thermal power plants, industries, domestic cooking/heating.
- Industrial Processes: Release of specific pollutants like SO2, NOx, CO, particulate matter, volatile organic compounds (VOCs).
- Mining Activities: Dust and particulate matter.
- Solid Waste Disposal: Burning of waste releases smoke, particulate matter, and toxic gases.
- Agricultural Activities: Burning of crop residue, use of pesticides/fertilizers (releasing ammonia).
- Major Pollutants & Effects:
- Oxides of Sulphur (SOx) & Nitrogen (NOx): Cause acid rain, respiratory problems.
- Carbon Monoxide (CO): Reduces oxygen-carrying capacity of blood, harmful especially for heart patients.
- Carbon Dioxide (CO2): Major greenhouse gas contributing to global warming.
- Suspended Particulate Matter (SPM): Fine solid or liquid particles suspended in air (dust, soot, smoke). Causes respiratory diseases (asthma, bronchitis), reduces visibility.
- Ozone (O3): Ground-level ozone (smog component) is harmful; stratospheric ozone is protective.
- Lead: Primarily from leaded petrol (now phased out largely), affects nervous system.
- Urban Air Pollution: Cities face higher air pollution due to dense population, high number of vehicles, industries, and construction activities. Smog (smoke + fog) is a common problem, especially in winter (e.g., Delhi).
- Impacts: Respiratory and cardiovascular diseases, acid rain damaging forests, lakes, buildings, contribution to climate change, reduced visibility.
5. Noise Pollution
- Definition: Unwanted or excessive sound that can disrupt human or animal life activity. Measured in decibels (dB).
- Sources:
- Industrial: Machinery, generators.
- Transport: Road traffic (vehicles, horns), railways, aircraft.
- Construction Activities: Heavy machinery, drilling.
- Community/Domestic: Loudspeakers (religious/political events, functions), generators, household appliances, loud music.
- Impacts: Hearing impairment, hypertension (high blood pressure), stress, sleep disturbance, reduced concentration and work efficiency, physiological and psychological effects.
- Spatial Variation: Noise levels are highest near major transport arteries (highways, railway lines, airports) and industrial areas.
6. Land Pollution / Degradation
- Definition: Deterioration of land quality due to human activities, reducing its productive capacity and ecological functions.
- Sources:
- Improper Waste Disposal: Dumping of untreated/unmanaged industrial and urban solid waste (municipal solid waste - MSW). Hazardous waste from industries is a major concern.
- Agricultural Practices: Excessive use of fertilizers and pesticides contaminates soil, monoculture depletes specific nutrients.
- Soil Erosion: Caused by deforestation, overgrazing, improper farming techniques on slopes, leading to loss of topsoil.
- Mining Activities: Overburden dumping, excavation destroys landforms and vegetation. Mine waste (tailings) can contain toxic substances.
- Land Use Changes: Conversion of forest or agricultural land for urban or industrial development.
- Waterlogging and Salinisation/Alkalinisation: Often due to faulty irrigation practices, especially in canal command areas.
- Impacts: Loss of soil fertility and agricultural productivity, contamination of soil and groundwater, health hazards, ecological imbalance, aesthetic degradation.
7. Urban Waste Disposal
- Problem: Rapid urbanization leads to massive generation of solid waste (garbage, trash). Collection and disposal systems are often inadequate.
- Types of Waste: Domestic waste, commercial waste, industrial waste (can be hazardous).
- Disposal Methods & Issues:
- Landfills: Most common method. Often unscientific open dumping sites, leading to groundwater contamination (leachate), air pollution (methane emission, burning), breeding grounds for pests and disease vectors.
- Incineration: Burning waste reduces volume but can cause air pollution if emissions are not controlled.
- Composting: Biological decomposition of organic waste. Requires segregation.
- Recycling & Reuse: Reduces waste generation but needs efficient collection and processing infrastructure.
- Impacts of Improper Disposal: Serious health hazards (spread of diseases by flies, rodents, mosquitoes), environmental pollution (air, water, soil), unpleasant aesthetics.
8. Rural-Urban Migration
- Definition: Movement of people from rural areas to urban areas.
- Causes:
- Push Factors (from Rural Areas): Poverty, unemployment/underemployment, low agricultural productivity, lack of basic amenities (education, health, electricity, sanitation), land pressure, social factors, natural disasters (droughts, floods).
- Pull Factors (to Urban Areas): Perceived employment opportunities, higher wages, better living standards, better educational and health facilities, entertainment, infrastructure.
- Consequences:
- In Urban Areas: Overcrowding, pressure on infrastructure (housing, water supply, sewage, transport, power), growth of slums and informal settlements, increase in crime rates, social tension, environmental pollution, strain on civic amenities.
- In Rural Areas: Depletion of workforce (especially young, able-bodied males), demographic imbalance (higher proportion of elderly and females), potential neglect of agriculture, remittances sent back can sometimes boost rural economy.
9. Problems of Slums (Jhuggi-Jhopri Clusters)
- Characteristics: Least choice locations (environmentally incompatible/degraded land), dilapidated structures, high density and congestion, lack of basic amenities (safe drinking water, sanitation, electricity, ventilation), unhygienic conditions, poverty, vulnerability to diseases.
- Socio-economic Issues: Inhabitants largely work in the informal sector (low wages, insecure jobs), suffer from poor health (malnutrition, water-borne diseases), face social exclusion, higher crime rates, drug abuse, alcoholism. Lack of education and skill development opportunities perpetuates poverty.
- Example: Dharavi in Mumbai is one of Asia's largest slums, characterized by extreme crowding, poor sanitation, but also a hub of small-scale industries and recycling activities.
10. Land Degradation (Revisited with Geographical Perspective)
- Definition: Temporary or permanent decline in the productive capacity of land.
- Processes & Affected Areas:
- Water Erosion (Sheet & Gully): Loss of topsoil by running water. Severe in areas with heavy rainfall and undulating topography (e.g., North-eastern states, Western Ghats, Chotanagpur plateau). Gully erosion creates ravines (e.g., Chambal basin).
- Wind Erosion: Removal of soil by wind. Common in arid and semi-arid regions (e.g., Rajasthan, Haryana, Gujarat).
- Waterlogging: Saturation of soil with water due to poor drainage, often in canal command areas (e.g., Punjab, Haryana, UP).
- Salinisation/Alkalinisation: Accumulation of salts on the surface due to excessive irrigation in dry areas with high evaporation or capillary action from saline groundwater. Affects large tracts in Punjab, Haryana, UP, Rajasthan, Gujarat.
- Causes (Human-induced): Deforestation, overgrazing, shifting cultivation, improper agricultural practices, mining, industrial waste dumping, excessive irrigation.
- Consequences: Reduced agricultural yield, food insecurity, environmental damage, desertification.
- Mitigation: Afforestation, controlled grazing, contour farming, strip cropping, construction of check dams, proper irrigation management (sprinkler/drip irrigation), reclamation of saline/alkaline soils, watershed management.
Conclusion:
Addressing these interconnected issues requires integrated planning, sustainable development practices, strict enforcement of environmental laws, technological solutions, community participation, and raising public awareness. A geographical perspective helps in identifying vulnerable areas, understanding the root causes, and formulating region-specific strategies.
Multiple Choice Questions (MCQs)
-
Which of the following is the most significant source of water pollution in India by volume?
a) Industrial effluents
b) Agricultural runoff
c) Domestic sewage
d) Oil spills -
Eutrophication in water bodies is primarily caused by:
a) Heavy metals from industries
b) High concentration of nutrients like nitrates and phosphates
c) Thermal pollution from power plants
d) Acid rain -
Which pollutant is mainly responsible for reducing the oxygen-carrying capacity of blood?
a) Sulphur Dioxide (SO2)
b) Carbon Monoxide (CO)
c) Suspended Particulate Matter (SPM)
d) Ozone (O3) -
Acid rain is primarily caused by the atmospheric emission of:
a) Carbon Dioxide and Methane
b) Chlorofluorocarbons (CFCs)
c) Oxides of Sulphur and Nitrogen (SOx and NOx)
d) Carbon Monoxide and Lead -
The 'Namami Gange Programme' primarily aims to:
a) Increase navigation in the Ganga river
b) Build large dams on the Ganga river
c) Abate pollution and rejuvenate the Ganga river
d) Promote tourism along the Ganga river -
Which of the following is NOT typically considered a 'pull factor' for rural-urban migration?
a) Better employment opportunities in cities
b) Poverty and lack of land in rural areas
c) Availability of better education and health facilities in cities
d) Higher wages in urban centres -
Slums in Indian cities are generally characterized by all the following EXCEPT:
a) High population density and congestion
b) Well-planned infrastructure and spacious housing
c) Lack of basic amenities like clean water and sanitation
d) Location on environmentally degraded or marginal lands -
Land degradation due to salinisation and alkalinisation is most common in which type of areas in India?
a) Areas with heavy rainfall and dense forests
b) Coastal regions prone to cyclones
c) Arid and semi-arid regions with intensive canal irrigation
d) Hilly regions with shifting cultivation -
Ravine formation, a severe form of gully erosion, is prominently found in the basin of which river?
a) Godavari
b) Mahanadi
c) Brahmaputra
d) Chambal -
Improper disposal of Municipal Solid Waste (MSW) through unscientific landfills poses a major risk of:
a) Ozone layer depletion
b) Increased agricultural productivity nearby
c) Groundwater contamination through leachate
d) Reduced noise pollution
Answer Key for MCQs:
- c) Domestic sewage
- b) High concentration of nutrients like nitrates and phosphates
- b) Carbon Monoxide (CO)
- c) Oxides of Sulphur and Nitrogen (SOx and NOx)
- c) Abate pollution and rejuvenate the Ganga river
- b) Poverty and lack of land in rural areas (This is a 'push' factor)
- b) Well-planned infrastructure and spacious housing
- c) Arid and semi-arid regions with intensive canal irrigation
- d) Chambal
- c) Groundwater contamination through leachate
I hope these notes and MCQs help you prepare effectively for your exams. Remember to correlate these issues with maps of India to understand their spatial distribution better. Good luck!