Air, water, and soil pollution

Among the various environmental concerns, those related to air, water and soil pollution are important issues in the wake of increasing industrialisation and urbanisation. Air, water, and soil pollution, their causes and methods for controlling them, are the most important issues that must be understood for effective management of global environmental problems. This makes it an important topic for students going in for Class 9 to NEET. This topic is a part of the class 12 biology chapter Environmental Issues.

Air Pollution

Air pollution refers to the contamination of the air as a result of the presence of compounds in the atmosphere that are dangerous to the health of people and other living organisms or that affect the environment or materials. Gases (such as ammonia, carbon monoxide, sulphur dioxide, nitrous oxides, methane, carbon dioxide, and chlorofluorocarbons), particulate matter (both organic and inorganic), and biological molecules are just a few examples of the many diverse forms of air pollutants. In addition to harming humans, animals, and food crops, air pollution can also impact climate change and cause ozone depletion or habitat degradation (for example, acid rain).

Also Read:

• Environmental Issues
• Biodiversity and Conservation
• Types Of Pollution
• Air Pollution And Its Control

Causes of Air Pollution

• Industries and Factories: The primary source of carbon monoxide, organic compounds, hydrocarbons, and chemicals in industry and manufacturing These degrade the quality of the atmosphere by dispersing into it.

• Fossil Fuel Exploitation: The combustion of fossil fuels emits a large amount of sulphur dioxide into the atmosphere. Carbon monoxide, produced when fossil fuels are burned inefficiently, also contributes to air pollution.

• Automobiles: Vehicle emissions, including those from trucks, cars, buses, and jeeps, harm the environment. These are the primary sources of greenhouse gases, and they also have negative health effects.

• Paints and home cleaning products release hazardous chemicals into the air. The fresh paint on the walls gives off the scent of the chemicals used to make the paint. Additionally, air pollution has an impact on respiration.

• Activities in Agriculture: One of the most dangerous chemicals released during agricultural operations is ammonia. Pesticides, fertilisers, and insecticides all harm the environment by releasing harmful gases.

• Mining Operations: Large pieces of machinery are used in the mining operation to remove the minerals from underneath the earth. In addition to polluting the air, the dust and chemicals emitted throughout the operation also harm the workers' and residents' health.

Effects of Air Pollution

Air pollution has caused a number of respiratory and cardiovascular diseases in humans. Over the last several decades, the incidence of lung cancer has increased. Children with asthma and pneumonia are more likely to reside close to polluted areas. Many people lose their lives as a direct or indirect result of air pollution each year.

Because of greenhouse gas emissions, the atmosphere's gaseous composition is out of balance. As a result, the earth's temperature has increased. This increase in the earth's temperature is referred to as "global warming." As a result, the sea level is rising and glaciers are melting, which might cause many cities to become submerged.

The major cause of the ozone layer's depletion is the atmospheric release of hydrochlorofluorocarbons, halons, and chlorofluorocarbons. The ozone layer's depletion does not shield people from the sun's dangerous ultraviolet rays, which can lead to eye and skin disorders.

Dangerous compounds like sulphur oxides and nitrogen oxides are emitted into the atmosphere when fossil fuels are burned. These contaminants react with the water droplets, making them acidic and causing acid rain, which harms both plant and animal life as well as people.

The air pollutants that are suspended in water bodies have an effect on aquatic life. Animals are often forced to leave their native habitats due to pollution. They become rare as a result, and numerous animal species have gone extinct as a result.

Prevention of Air Pollution

• Using public transportation for commuting

• Reuse and recycling of products

• Avoid burning trash and smoking.

• Use clean sources of energy like solar, wind, etc.

• When not in use, turn off electric appliances.

• Avoid using fireworks.

Water Pollution

Water pollution is the discharge of pollutants into underground water or into lakes, streams, rivers, estuaries, and seas to the extent that the chemicals interfere with the beneficial use of the water or with the ecosystems' normal functioning. Water pollution can also involve the discharge of energy into bodies of water in the form of radioactivity or heat, in addition to the release of substances like chemicals, debris, or microorganisms. The four primary causes of water pollution are sewage discharges, industrial activity, agricultural activity, and urban runoff, including stormwater. Surface water pollution (either freshwater pollution or marine contamination) and groundwater pollution are two categories that fall under "water pollution."

Sources of Water Pollution

There are two types of sources of water pollution: point sources and nonpoint sources:

Point Sources: Individual, definite sources or sources from which a definite path of travel into the watershed may be identified, including storm drains, sewage plants, oil spills, etc.

Non-Point Sources: Diffuse sources of pollution originating from an identifiable, diffuse source. Examples include agricultural runoff.

Common Pollutants

Organic and Inorganic Substances:

• Oils
• Metals
• Plastics
• Pesticides
• Persistent Organic Pollutants

Physical and Chemical Changes:

• Changes in salinity, pH, turbidity, and temperature.
• Disease-causing microorganisms.
• Heat as a pollutant. This is often caused by industries or power plants that cool themselves by releasing heat into the water.

Effects of Water Pollution

The impact of water pollution is determined by the kind of pollutants present and their concentration. The location of water bodies is also essential in estimating pollution levels.

• Extreme pollution exists in the water bodies close to metropolitan cities. This is the outcome of industrial and commercial facilities discharging trash and hazardous chemicals into the water bodies.

• Aquatic life is significantly impacted by water pollution. Their behaviour and metabolism are altered, which leads to illness and eventual death. Dioxin is a toxin that affects many processes, including reproduction, uncontrolled cell proliferation, and cancer.

• This substance bioaccumulates in fish, fowl, and meat. Toxic substances go up the food chain before they enter the human body.

• Water contamination has the potential to drastically alter, demolish, and harm the ecosystem.

• Pollution affects people, and when faeces are present in water sources, people are more likely to contract illnesses. Infectious illness outbreaks like cholera and others are always a possibility when drinking water quality is poor or inadequate.

• The food chain may be significantly impacted by water contamination. The food chain is disrupted. Some hazardous compounds, such as cadmium and lead, can cause further disruption at higher levels after entering the food chain via animals (fish eaten by both animals and humans).

Prevention of Water Pollution

• Greater degrees of water pollution can be reduced using a variety of methods. Treatment of sewage waste prior to discharging it into aquatic bodies is preferable.

• By doing this, the original toxicity can be reduced, and the body of water itself can break down and render harmless any compounds that are still there. If it has undergone secondary treatment, water can be reused in sanitary systems and agricultural sectors.

• The water hyacinth is a particularly special plant with the capacity to take in toxic elements in solution, including cadmium and other comparable substances. Establishing these in areas vulnerable to these types of pollution will significantly lessen the negative consequences.

Soil Pollution

When harmful chemicals (also known as pollutants or contaminants) are present in the soil at levels high enough to endanger both human health and the ecosystem, this is referred to as "soil pollution." Simply said, "soil pollution" is the term used to describe changes made to the natural soil as a result of human activity. Industrial activities, agricultural chemicals, or inappropriate waste disposal methods are the main causes of soil pollution. Petroleum hydrocarbons, polynuclear aromatic hydrocarbons (including naphthalene and benzo(a)pyrene), solvents, insecticides, lead, and other heavy metals are the most frequent compounds involved in soil pollution. The level of industrialization and the number of chemical substances are associated with contamination. The main effects of soil pollution are health risks due to direct contact with contaminated soil, inhalation of contaminant vapour, or secondary contamination of water supplies contained within and beneath the soil.

Causes of Soil Pollution

• Dumping of industrial waste, plastics, domestic waste, and electronic waste leads to soil contamination.

• Mining and manufacturing activities lead to a vast amount of soil degradation.

• excessive usage of pesticides, herbicides, etc. in agricultural practices

• Heavy metals (like lead and mercury) can become extremely dangerous for humans when they are present in soils at very high concentrations.

• Because batteries contain hazardous chemicals, disposing of electrical products like batteries has a negative impact on the soil in the same way that disposing of plastics and other solid garbage does.

• Acid rain can cause soil contamination.

• Dumping radioactive waste leads to soil pollution.

Effects of Soil Pollution

• Human health is significantly impacted by soil contamination. Most of the pollutants are absorbed by crops and plants growing in contaminated soil, which subsequently transfer them to humans. Infections brought on by soil pollution include skin and eye irritation, headaches, motion sickness, coughing, chest pain, and wheezing.

• The fertility of the soil will be reduced and the soil's structure will be altered by the regular use of chemical fertilisers, inorganic fertilisers, and pesticides. This will result in a decline in soil quality and subpar crops. The land is no longer suitable for cultivation or for the survival of any native plants due to slowly deteriorating soil fertility.

• Different kinds of microbes, birds, and insects depend on the soil as a vital habitat. Thus, altering the chemistry of the soil has the potential to have a detrimental effect on living things and even cause the progressive death of a large number of organisms.

Prevention of Soil Pollution

• Reduce the use of chemical fertilisers, inorganic fertilisers, pesticides, and herbicides. Use eco-friendly fertilisers to improve soil fertility.

• Afforestation and reforestation should be encouraged.

• Reduce, reuse, and recycle the products so that the dumping of huge amounts of waste can be prevented.

• One of the finest sources of nutrients for the soil is natural manure. It's fully safe and natural. It promotes the general health of the soil and replenishes vital nutrients. It doesn't generate any hazardous byproducts that could endanger the ecosystem or the land.

Tips and Tricks to Prepare for Air, Water, and Soil Pollution

• Study aids: Use diagrams to identify the sources and effects of pollution on ecosystems.
• Mnemonics: For pollution control methods use "R3" Reduce, Reuse, Recycle.
• Examples in real life: Connect the types of pollution with examples of real-life cases, for example, Bhopal Gas Tragedy in the case of air pollution.
• Multimedia: View animations or video clips illustrating the processes of pollution and pollution control.
• Flashcards: Flashcards will help memorize key terms, which should include eutrophication, acid rain, and bioremediation.

Weightage of Air, Water, and Soil Pollution Topics in Exams

Given below is the weightage of questions asked from pollution topics in different exams:

Types Of Questions Asked from Air, Water, and Soil Pollution Topics in Different Exams:

The table given below indicates the types of questions asked in various exams on this topic:

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