Carbon Cycle

Carbon cycle can be understood by analyzing where it is found and how it moves from one location to the other.


Custom Search

Let us have a look at the following diagram.

Carbon Cycle

  Image Source : NASA 

Carbon is found :

1] in the atmosphere as Carbon Dioxide CO₂

2] on land – on fossil fuels, rocks, shells, soil,

3] in ocean as also in lakes and rivers where it is dissolved,

4] in plants,

5] in animals,

6] in humans.

The processes through which Carbon passes in the cycle are as follows :

a) Photosynthesis:

Plants use Carbon Dioxide CO₂ from the atmosphere through the process of Photosynthesis for their growth and give out Oxygen back to it.

Newer plants use the process more vigorously than older plants.

b) Respiration:

Both humans and plants are active in the process of respiration.

We humans give out carbon to the atmosphere in the form of Carbon Dioxide, while plants give out Oxygen.

The plants in ocean also cause the movement of carbon to the ocean water through photosynthesis and respiration like on land.

c) Decomposition:

When plants and animals die they decompose and get stored in the soil. In course of several years they get converted into fossil fuels like oil or coal.

The movement of carbon through the oceans and the atmosphere is called diffusion.

Just like on land, ocean animals like fish eat plants in the oceans. They exhale carbon dioxide into the ocean’s water.

When they die, they decompose just like on land and either dissolve in the ocean water and get buried in the ocean’s bottom.

Humans extract coal and oil from the soil and use them for producing energy by burning them.

In this process we generate CO₂ and release it to the atmosphere.

Deforestation or destruction of forests for :

  • Agricultural purposes

  • Grazing of cattle

  • Developing infra structure and building commercial complexes

  • Cement manufacturing plants, chemical plants and other such pollutants emitting plants

  • Extraction of minerals like copper, manganese, aluminum or petroleum products from the ground

  • Burning wood sometimes causing forest fires etc
  • are other processes by which we humans release carbon into the atmosphere.

    Return to Home Page from the Carbon Cycle page