Decomposition

Decomposition is the process by which dead organisms and waste products are broken down by decomposers — mainly bacteria and fungi. This process is vital for recycling nutrients in ecosystems and is an important topic in AQA GCSE Biology. This lesson also covers the Required Practical on the effect of temperature on the rate of decomposition.

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What Is Decomposition?

Decomposition is the breakdown of dead plant and animal material (and waste such as faeces and urine) by microorganisms, mainly bacteria and fungi. These organisms secrete enzymes onto the dead material, which digest it externally, and then absorb the soluble products.

Decomposition returns nutrients and mineral ions to the soil, where they can be taken up by plant roots and used for growth. Without decomposition, dead material would accumulate indefinitely and the supply of minerals in the soil would eventually run out.