Uses of Decomposition

Anaerobic Decay

Anaerobic decay is the process by which organic matter is decomposed in the absence of oxygen. This process is carried out by anaerobic bacteria and other microorganisms, which are able to survive and thrive in environments where there is little or no oxygen.

Anaerobic decay is typically slower than aerobic decay. This is because aerobic decomposers, such as fungi and bacteria, are able to break down organic matter more quickly and efficiently due to the availability of oxygen.

Anaerobic decay usually happens in wet or submerged environments like swamps, marshes, and bodies of water. In these environments, the lack of oxygen often makes it difficult for aerobic decomposers to survive. Instead, anaerobic decomposers take over the process of decomposition.


Anaerobic respiration produces biogas as a byproduct. Biogas is a mixture of gases that forms when organic matter breaks down in the absence of oxygen. It consists of methane (CH4), carbon dioxide (CO2), and small amounts of other gases.

  • Biogas is often used as a renewable energy source and can be burned for heating, cooking, or electricity generation.

Biogas generators are large containers that use anaerobic digestion to turn organic matter, like animal waste or crops, into biogas. They can convert domestic waste into renewable biogas and reduce the amount of waste sent to landfills.

An illustrative diagram of a biogas production system set against a sandy background. On the left, a tractor tips organic waste into an inlet chute, overseen by a worker holding a clipboard. The waste travels down into a large underground tank labelled 'slurry'. As it breaks down, biogas rises and is captured, travelling through a 'biogas pipe' to a storage tank above ground, labelled 'biogas'. There's an access cover on top of the storage tank. The residual solid waste, called 'digestate', moves to a separate section and is directed to an outlet on the right. The entire system is sealed, and there's a tree in the top right corner with clouds overhead.
  • The inlet is for animal and plant waste material, whereas the outlet is for decomposed material, which can be used as a crop fertiliser

Biogas generators play an important role in waste management and improving sustainability. They provide an alternative to traditional fossil fuel sources and reduce the environmental impacts of waste disposal.

Gardeners and Farmers Using Compost

For gardeners and farmers, decomposition is very beneficial as it enriches the soil and improves its fertility. When organic matter is decomposed, bacteria and other decomposers release nutrients such as mineral ions, which can be absorbed by plants and used for growth. This improves the overall health and productivity of a garden or farm.

In addition to enriching the soil, decomposition can also help to improve the structure of the soil. As organic matter breaks down, it makes the soil more porous (there are many tiny holes). This can improve drainage and allow for better root growth, which is important in areas where the soil is heavy or hard.

Decomposition can also help to reduce the amount of waste produced by a garden or farm. By breaking down organic matter, decomposers can help reduce garden or farm waste, making it easier to dispose of or recycle. This can be especially important for large-scale operations, where managing waste can be a huge challenge.

Finally, decomposition can also help to reduce the need for synthetic fertilisers, as the nutrients released during decomposition can help to naturally fertilise the soil. This can be more environmentally friendly and cost-effective than relying on synthetic fertilisers, which may have negative impacts on the environment.

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