Decomposition

https://www.revisely.com/gcse/biology/aqa/video/pND

What do decomposers such as bacteria / fungi do

Return carbon back to atmosphere, and also mineral ions back to the soil

What are the optimal conditions for decomposition

Temperature, take place faster in warmer temps, thats because decomposers use enzymes to break down plant materials, they work faster in warm conditions.

The amount of water, decomposing microorganisms work faster if compost is moist, this is because many of chemical reactions in decay require water.

The amount of oxygen, decomposers carry out aerobic respiration, requires good supply of oxygen. Many gardeners use gardening fork to mix compost regularly, allows more oxgen into the centre.

What happens if compost becomes too hot

They tend to be quite warm anyway, this is because decomposers release energy when they carry out aerobic respiration, if it gets too hot , the enzymes in decomposers can denature and they can die

What happens if there is no oxygen

Decomposing microorganisms carry out anaerobic decay, produces a mixture of gases including methane, this is called biogas.

Whats biogas used for

Small scale biogas generators provide fuels for homes, these often use plant materials such as food waste or animal manure.

Whats a compost heap

Gardeners put dead plant matrerial such as grass onto the compost heap, overtime bacteria and fungi decompose the plant material and produce compost, they can use this as natural fertiliser, as compost is rich in the minerals plants need to grow.