Pollution and Population Growth

Pollution and Population Growth

Pollution

Unwanted changes in the chemical and physical features of air, water and land (environment) that are dangerous to humans and other organisms, their life conditions, industrial processes and cultural achievements are called pollution.

Types of Pollution

The types of pollution are mainly –

1. Air pollution

2. Water pollution

3. Sound pollution

4. Soil pollution

5. Nuclear pollution

1. Air Pollution

When pollutants are present in the atmosphere and the quality of the atmosphere reduces, then it is called air pollution.

Main Air Pollutants

• Carbon monoxide (CO), Sulphur dioxide (SO₂), Hydrogen sulphide (H₂S), Hydrogen fluoride (HF), Nitrogen oxide (NO and NO₂), hydrocarbons, Ammonia (NH₃), tobacco smoke, Fluorides smoke and particles of smoke, aerosols, etc.

• Carbon monoxide gets combined with haemoglobin more rapidly than oxygen.

• Sulphur dioxide (SO₂), sulphur trioxide (SO₃), and nitrogen oxide (NO) react with environmental water and form sulphuric acid and nitric acid.

• These acids reach the earth with rainwater called acid rain.

• On 3rd December, 1984, an incidence of leakage of methyl isocyanate gas took place in the fertiliser-making Union Carbide Factory (Bhopal).

• The most important indoor air pollutant is radon gas.

2. Water Pollution

Mixing of unwanted substances in water is called water pollution. Only 2.5% to 3% of the water present on the earth is usable.

Sources of Water Pollution

• The water pollution takes place mainly due to the mixing up of carbonate, sulphates of magnesium and potassium, ammonia, carbon monoxide, carbon dioxide and industrial remains in water.

• Seawater pollution is due to the mixing up of heavy metals, hydrocarbons, petroleum, etc. in water.

• Oil spilt from the tanker spread soon on the surface of seawater.

• Contaminated water in which mercury is present causes Minamata disease.

• Pollution of river water is measured by oxygen dissolved in it.

• In some parts of India arsenic is found as a pollutant in drinking water.

• Ozone, chlorine dioxide and chloramines are used as disinfectants of water.

3. Sound Pollution

The unwanted and undesirable sound scattered in the atmosphere is called sound pollution.

Source of Sound Pollution

• The source of sound pollution is loud sound or noise, in whatever way it has been produced.

4. Soil Pollution

A distorted form of soil which changes its chemical nature is called soil pollution.

Source of Soil Pollution

• Acid rain, water from mines, excessive use of fertilisers and germicide chemicals, garbage, industrial remains, excretion in open fields, etc. are the main sources of soil pollution.

5. Nuclear Pollution

This pollution is created by radioactive rays.

Sources of Radioactive Pollution

(a) Pollution from the rays which are used in treatment.

(b) Pollution created from fuels used in atomic reactors.

(c) Pollution created from the use of nuclear weapons.

(d) Pollution created by remaining substances coming out of atomic powerhouses.

Other Important Points Related to Pollution

• The pollutant responsible for the ozone hole is CFC.

• One of the best solutions to get rid of non-biodegradable waste is recycling.

• Vermicomposting is done by worms.

• Soil erosion can be prevented by afforestation.

• Natural sources of air pollution are volcanic eruptions.

• The best indicator of SO₂ pollution is lichen.

• Positive pollution of soil is due to excessive use of fertilisers.

• A green muffler is used against noise pollution.

• Photochemical smog formed in congested metropolitan cities mainly consists of ozone, peroxyacetyl nitrate and NO₂.

• DDT is a non-biodegradable pollutant.

Population and Biotic Community

Population

• A population is a group of individuals of the same species occupying the same area at a given time.

Population Density

• Total number of individuals present per unit area.

Natality

• An increase in the number of individuals in a given population by birth is called natality.

Mortality

• The number of individuals removed from a population due to death under given environmental conditions at a given time is called mortality.

Biotic Potential

• It refers to the maximum inherent capacity of an organism to reproduce.

Environmental Resistance

• Environmental factors, which put a check on the growth of population.

Types of Ecological Relationships

Mutualism

• It is a functional association between two different species in which both the species benefit.

Commensalism

• It is an association between individuals of two different species in which one species is benefited and the other one is neither benefited nor affected.

Population Explosion

• The dramatic increase in population size over a relatively short period is called population explosion.

Demographic Transition

• If the birth rate is equal to the death rate, it results in zero population growth, which is called demographic transition.

Human and Environmental Health

Psychosis

• It is a mild form of mental illness where the patient shows a prolonged emotional reaction.

Drug Abuse

• When drugs are taken for a purpose other than their normal clinical use in an amount that impairs one’s physical, physiological and psychological function of the body, it is called drug abuse.

Biosphere and Biogas

Biosphere

• The space retaining life in any form is called the biosphere.

Biogas

• Methane released from the biogas plant is used as fuel gas.

Final Thoughts

Pollution and population growth are two major factors affecting the ecosystem and overall environmental balance. Pollution occurs when harmful substances contaminate air, water, or soil, leading to serious impacts on humans, animals, and plants. The rapid increase in population adds pressure on natural resources, causing more waste, deforestation, and industrial emissions.

Air, water, soil, and noise pollution together disturb the natural cycles essential for life. As the population expands, the demand for food, energy, and land increases, intensifying ecological damage.

Understanding these issues helps promote sustainable living, pollution control, and environmental conservation for a balanced and healthier planet.