CONSEQUENCE OF HUMAN INTERFERENCE IN NATURE
Objectives
The student will be able to:
o Identify human activities that bring about undesirable change in the natural environment.
o Explain the term pollution, causes and its effects on the environment.
o Discuss ways and means of controlling pollution.
o Describe the Integrated Water Resources Management and explain how it can reduce undesirable change in the natural environment.
Human Activities and the Environment
As the human population continues to increase and standards of living improve, there is a serious danger of a permanent change to the global environment. This growing concern demands immediate attention to preserve our planet for future generations.
Agriculture and Environmental Impact
To meet the food requirements of an increasing population, more forest lands have been converted into farming lands. The use of fertilizers, insecticides, and weedicides on these farms can lead to soil acidity, harming both microorganisms and macro-organisms in the soil. When these chemicals are washed into water bodies, they make the water unfit for drinking, posing significant health risks. For more information on sustainable farming practices, visit FAO's guide on sustainable agriculture.
Industrial Activities and Pollution
Human activities such as quarrying, the use of chemicals for fishing (e.g., DDT), and building industries and dams disturb the natural environment. Burning fossil fuels in vehicles produces carbon dioxide, contributing to the greenhouse effect. Improper disposal of sewage and refuse, especially into water bodies, causes serious water pollution. To learn more about the impact of industrial activities on the environment, refer to the EPA's industrial pollution page.
Pollution
Pollution is the release of substances or energy into the environment that can cause harm to living organisms and other resources. Almost all human activities, either directly or indirectly, contribute to pollution. The substances that cause pollution are called pollutants.
Types of Pollutants
Biodegradable Pollutants: These pollutants can be easily broken down under natural conditions by microorganisms, making them less harmful. Examples include excreta, sewage, and pollen grains.
Non-Biodegradable Pollutants: These pollutants cannot be broken down under natural conditions or take an extremely long time to decompose. Examples include plastics, DDT, and metal wastes such as lead, mercury, and arsenic.
For more detailed information on pollutants, visit National Geographic's pollution guide.
Activities of Man That Pollute the Environment
Agriculture
- Chemicals used by fishermen pollute water bodies, such as DDT.
- Runoffs from fertilizers pollute the water.
- Pesticides pollute the atmosphere, and their runoffs contaminate water bodies.
Industry
- Radioactive wastes pollute air, water, and land.
- Scrap metal and plastic containers pollute the land.
- Oil spills pollute water and land.
- Thermal (heat) pollution affects water bodies.
- Mining industry pollutes air with dust.
Domestic
- Improper disposal of refuse pollutes the environment.
- Release of untreated sewage pollutes water.
- Use of fossil fuels releases carbon dioxide, carbon monoxide, lead oxide, and smoke into the atmosphere.
To learn more about how different sectors contribute to pollution, check out UN Environment Programme's overview.
Effects of Sewage on Aquatic Life and Humans
- Makes water unfit for drinking or swimming.
- Leads to offensive odors.
- Poisonous substances may enter the food chain, posing risks to humans.
- Nitrates and phosphates can enrich water, promoting rapid growth of plants and algae, a process known as eutrophication. This reduces light penetration and the rate of photosynthesis in aquatic plants and algae.
- Reduced oxygen content leads to suffocation and death of aquatic life.
- Gills of fish and filters of filter feeders may be clogged by particulate matter in sewage.
For more on the impact of sewage on water bodies, visit World Health Organization's water pollution page.
Types of Pollution
The major types of pollution are:
- Air Pollution
- Water Pollution
- Noise Pollution
- Thermal Pollution
- Soil Pollution
Air Pollution
Air is a crucial natural resource providing the basis of life on Earth. The composition of air (78% nitrogen, 21% oxygen, 0.03% carbon dioxide) is necessary for the existence of life. Impairment of air composition directly affects the living conditions of plants and animals.
Gaseous Pollutants: These include carbon monoxide, carbon dioxide, nitrogen oxides, sulfur dioxide, chlorofluorocarbons (CFCs), smoke, odors, and fumes from acids.
Effects of Major Air Pollutants
Carbon Dioxide (CO2)
- Causes global warming or the "greenhouse effect."
- Reduces oxygen levels in the atmosphere.
- In poorly ventilated areas, it may cause headaches.
- Increases the rate of photosynthesis, enhancing plant productivity.
Sulfur Dioxide (SO2)
- Damages the respiratory system.
- Irritates the eyes.
- Contributes to acid rain, which corrodes metals, stonework, and bricks, and acidifies soil.
Chlorofluorocarbons (CFCs)
- Cause ozone depletion.
- Lead to inflammation of the lungs and suffocation.
- Increase the risk of skin cancer and skin diseases.
Smoke and Fumes
- Cause difficulty in breathing and respiratory tract injuries.
- Reduce visibility.
- Cause discomfort to the eyes and reduce photosynthesis in plants.
For more information on air pollution and its effects, refer to Environmental Protection Agency's air quality page.
Control of Air Pollution
- Enforce strict laws on factory emissions.
- Regularly check vehicle exhaust gases.
- Reduce lead pollution by using lead-free petrol and paint.
- Implement control measures to prevent accidental industrial pollution.
- Safely dispose of atomic wastes.
- Ban illegal burning of hazardous materials.
- Plant more trees to reduce carbon dioxide levels.
- Educate the public and enforce laws to ban smoking in public places.
Noise Pollution
Noise is generally regarded as an unwanted sound or sound that produces unpleasant effects on the ears. Noise has severe adverse effects on the quality of human surroundings.
Pollutants of Noise: These include industrial noise, vehicle noise, horns, gunfire, jet planes, loudspeakers, thunder, and generators.
Effects of Noise Pollution
- Impairment of hearing.
- Hypertension or increased heart rate.
- Emotional disorders or lack of concentration.
- Headaches, irritability, and nervousness.
- Adverse effects on the developing embryo in a mother's uterus.
Control of Noise Pollution
- Ban the use of horns with jarring sounds.
- Locate factories, aircraft, and railway stations away from residential areas.
- Enforce laws on the misuse of loudspeakers and public announcement systems.
- Create silence zones near schools, colleges, hospitals, etc.
- Plant trees along roadsides to absorb sound.
For more details on noise pollution, visit Centers for Disease Control and Prevention's noise and hearing loss prevention page.
Soil or Land Pollution
Soil pollution refers to the addition of solid and liquid wastes to the soil, creating an imbalance in its natural composition and functions. It is caused by industrial activity, chemicals used in agriculture, and improper disposal of waste.
Effects of Soil Pollution
- Reduction in soil fertility.
- Loss of natural nutrients in the soil.
- Increased soil salinity, making it unfit for cultivation.
- Health problems from consuming crops grown on polluted soil.
- Creation of toxic dust.
- Poor quality of fruits and vegetables grown on contaminated soil.
Control of Soil Pollution
- Ban the use of plastic bags below 20 microns thickness.
- Recycle plastic wastes.
- Ban deforestation and encourage plantation programs.
- Limit the use of some pesticides and fertilizers.
- Bury refuse and sewage in deep pits.
For more information on soil pollution and its control, refer to Food and Agriculture Organization's soil pollution page.
Water Pollution
Water pollution is the contamination of natural water bodies like lakes, rivers, streams, oceans, and groundwater due to the inflow or deposition of pollutants. This pollution often results from human activities and can significantly impact all living species.
Effects of Water Pollutants
- Sewage: Includes domestic, hospital wastes, and animal and human excreta, causing oxygen depletion and the spread of diseases.
- Metals: Mercury and other metals from industries are poisonous, causing deafness, blurred vision, and mental disorders.
- Lead: Industrial waste containing lead affects red blood cells, bones, the brain, liver, kidneys, and the nervous system.
- Arsenic: Fertilizers contain arsenic, causing renal failure, liver and kidney disorders, and nervous system issues.
- Agrochemicals: Pesticides like DDT accumulate in fish, birds, mammals, and humans, affecting the nervous system and fertility.
- Bacteria, Viruses, and Parasites: Sourced from human and animal excreta, these infectious agents pose significant health risks.
- Plastics, Detergents, Oil Spillage, and Gasoline: These substances cause organic pollution and are harmful to health.
Control of Water Pollution
- Treat raw sewage before releasing it into water bodies.
- Reuse treated water for non-drinking purposes.
- Ban unsafe dumping of industrial wastes.
- Discourage the use of chemicals and dynamite in fishing.
- Recycle city wastes.
- Cool hot water before discharge.
- Encourage biological methods of pest control.
- Reduce the use of pesticides and fertilizers.
- Adopt septic tanks and better sanitation in homes and schools.
- Establish public health centers for health education.
For more information on water pollution and its control, visit World Health Organization's water sanitation page.
By understanding and addressing these various types of pollution, we can work towards a cleaner, healthier environment. For further reading on environmental conservation, refer to the United Nations Environment Programme and the Environmental Protection Agency.
SSCE/WASSCE/GCE PAST QUESTIONS AND ANSWERS
1.
Which of the ways of
controlling bilharzia can result in pollution?
A. clearing water
weeds on which the snail feed
B. Treating infected
people with drugs
C. Preventing
contamination of water by infected urine and faeces
D. Applying chemical to
kill the snail
2.
Which of the following is a
dangerous product of coal burning?
A. Sulphur dioxide C. Carbon
B. Carbon dioxide D. Nitrogen
3.
Which of the following
constitute pollution?
A. Droppings from
birds
B. loud disco sound
C. A pack of
cigarettes
D. Refuse in an
incinerator
4.
Source of air pollutants
are
A. industrial
chimneys, burning fossil oils and river dam
B. sulphur dioxide,
acid rain and pesticide
C. sulphur mines,
vehicle exhausts and aerosols
D. sewage, smoke and old
vehicle
5.
Carbon monoxide poisons
tissue by
A. constricting the
blood vessels
B. killing the cells
C. combining with
haemoglobin
D. rupturing the blood
vessels
6.
Environmental pollutants
which can work through the media of water, soil and air include
A. carbon monoxide B. noise
C. sulphur (IV) oxide D. smoke
7.
One of the most effective
ways of controlling guinea worm is by
A. treating the
disease
B. public
enlightenment campaigns
C. accelerating
rural development
D. provision of portable
drinking water
8. The pollutants that contribute to the depletion of the ozone layer
in the atmosphere are
A. radioactive
materials
B. oxides of sulphur
C. oxides of carbon
D. chlorofluorocarbons
9. Carbon (IV) oxide content of the atmosphere is least affected by
A. cutting down and
clearing of forests
B. forest fires
C. burning of fossil
fuels
D. plant and animal
respiration
10. The greatest influence on a stable ecosystem in nature is exerted by
A. man C. animals
B. pollution D. rainfall
11. The excessive use of agro-chemicals could lead to the pollution of
A. the lithosphere C. fresh water
B. the atmosphere D. space
12. The most effective method of dealing with non-biodegradable
pollutant is by
A. Dumping C. Incineration
B. Recycling D. Burying
13. Which of the following may not contribute to environmental
pollution?
A. Solar energy
radiation C. Smoke
B. Industrial waste D. Waste disposal
14. Which of the following water pollutant may contain organisms that
cause dysentery?
A. Pesticides C. Industrial wastes
B. Sewage D. Fertilizers
15. Which of the following is not a way of reducing air pollution?
A. Siting factories
and power stations away from residential areas
B. Building tall
factory chimneys
C. Passing waste
gases through filters and absorbers
D. Recycling tins, cans
and bottles
16. Which of the following is not a way of controlling pollution?
A recycling of
industrial waste
B. use of cars
fitted with efficient engines
C. cooking meals
under hygienic
D. treatment of raw
sewage
17. Water bodies are polluted by
A. carbon
dioxide C. fluorine
B. fertilizers D. sulphur dioxide
18. Which of the following products constitute land pollution?
A. heavy metals and
oil
B. pesticides and
detergent
C. Refuse and hot
water
D. heavy metals and
refuse
19. Which of the following wastes is correctly linked to it sources?
A. Raw sewage from
agricultural practices
B. Hot water from
homes
C. spilled oil from
industries
D. detergents from
industries
20. Depletion of ozone layer will result in
A. reduction in human
immunity to diseases
B. destruction of
the screen against ultraviolet rays of the sun
C. lowering the
concentration of atmospheric oxygen
D. reduction in annual
rainfall
Answers
|
1. D |
6. C |
11. C |
16. C |
|
2. A |
7. D |
12. B |
17. B |
|
3. B |
8. A |
13. D |
18. D |
|
4. C |
9. A |
14. B |
19. D |
|
5. C |
10. B |
15. D |
20. B |
1.
(SSCE
1995, Q5) (a). What is pollution?
(b). Discuss two activities of man which pollutes the environment.
(c). Discuss the measures that can be taken to control water pollution.
