Acid Rain, Ecosystem, Formation of Acid Rain, Causes of Acid Rain, Effect of Acid Rain

Glide to success with Doorsteptutor material for UGC : Get detailed illustrated notes covering entire syllabus: point-by-point for high retention.

Acid Rain

The rainwater which contains a large amount of poisonous acids like sulphuric acid, sulphurous acid, nitrous acid and other pollutants is known as the Acid Rain.

Formation of Acid Rain

  • Acid rain is caused by a chemical reaction that begins when compounds like sulphur dioxide and nitrogen oxides are released into the air. These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain.

  • Sulphur dioxide and nitrogen oxides dissolve very easily in water and can be carried very far by the wind. As a result, the two compounds can travel long distances where they become part of the rain, sleet, snow, and fog that we experience on certain days.

Causes of Acid Rain

  • Human activities are the main cause of acid rain. Over the past few decades, humans have released so many different chemicals into the air that they have changed the mix of gases in the atmosphere.

  • Power plants release the majority of sulphur dioxide and much of the nitrogen oxides when they burn fossil fuels, such as coal, to produce electricity. In addition, the exhaust from cars, trucks, and buses releases nitrogen oxides and sulphur dioxide into the air. These pollutants cause acid rain.


The main causes of acid rain are… Natural Sources:

  • Lightning strikes (cause nitrogen molecules to be oxidized)

  • Combustion of hydrogen sulphide (hydrogen sulphide is formed from the breakdown of sulphates in organic matter in the absence of oxygen- anaerobic conditions). This reaction forms sulphur dioxide.

Human Sources

  • Combustion engines (car, airplanes etc.)

  • Burning of fossil fuels and coal

  • Some mineral ores contain sulphur dioxide, and this is released when the minerals are processed.

Effect of Acid Rain

  • Kills flora and fauna

  • Damages the buildings

  • Causes skin cancer

  • Increases the acidity of the soil

  • Kills fish and other aquatic animals

  • Pollutes the water

  • Causes spotting of leaves

  • Causes corrosion of metal, painted surfaces and even stone buildings and monuments.



A natural of habitat or system where living organisms and physical components of their environment interact with one another and exchange materials so as to achieve a functional stability is called an ecosystem.

Characteristics of Ecosystem

  • An ecosystem is a basic unit of ecology of living organisms.

  • An ecosystem may be natural like a pond, lake, stream, river, ocean or a forest.

  • It may also be artificial like an Aquarian, an artificial pond or an agricultural field.

  • A pond is an excellent example of a small ecosystem to demonstrate interrelationship between abiotic and biotic component of the ecosystem.

Components of Ecosystem

Abiotic Components of Ecosystem. Following are the abiotic components of ecosystem.

  • Light

  • Temperature

  • Water

  • Atmosphere and wind

  • Fire

  • Soil

  • Topography

  • Gravity

  • Inorganic nutrients

Biotic Factors. Following are the biotic components of ecosystem.

  • Producers: Green Plants

  • Consumers: Animals and Man

  • Decomposers and reducers: Bacteria, fungi

Types of Ecosystem

There are two main types of ecosystem:

  • Terrestrial Ecosystem: it includes Forest and Desert Ecosystem

  • Aquatic Ecosystem: it includes small pool, a pond, stream, river, lake and an oceanic ecosystem.