Understanding Decomposition

  • Decomposition is the natural process of dead organic matter being broken down into simpler substances by organisms known as decomposers.
  • These simpler substances are further used by different organisms in the ecosystem, making decomposition an integral part of the nutrient cycle.
  • Decomposition plays a crucial role in nutrient recycling, returning the various nutrients locked in the organic matter back into the environment.


  • Decomposers are often microorganisms such as bacteria and fungi, though many invertebrates, such as worms, also contribute.
  • These Decomposers feed upon dead organic material - dead plants and animals, faeces, and the dead remains of other decomposers.
  • Through the process of decomposition, these organisms obtain energy, and in doing so, they break down complex organic substances into simpler inorganic substances.

Decomposition Process

  • Decomposition occurs in stages, starting with the break down of complex organic compounds into simple carbon compounds through the action of decomposers.
  • Following this, the carbon compounds are then broken down further into carbon dioxide through a process known as mineralisation.
  • Finally, the carbon dioxide is reused by primary producers (plants) during photosynthesis.

Impacts of Decomposition

  • Decomposition helps maintain the ecological balance. Without the process, dead organic waste would accumulate, potentially inhibiting life.
  • The nutrients released from decaying matter enrich the soil, promoting plant growth.
  • Through decomposition, carbon is recycled back into the ecosystem, contributing to the global carbon cycle.