decomposition (triple)

• Conditions required for decomposition (decay)

  • Temperature
  • Amount of water
  • Amount of oxygen
• Decomposition takes place faster at warmer temperatures


  Decomposers use enzymes to break down plant materials, and these enzymes work faster in warm conditions
• Compost heaps tend to be quite warm because decomposers release energy when they carry out aerobic respiration
• It's important that the compost does not get too hot, as this can denature the enzymes and kill the decomposers
• Decomposing microorganisms work faster if the compost is moist


  Many of the chemical reactions in decay require water
• It's important that gardeners do not allow a compost heap to dry out
• Decomposers


  • Carry out aerobic respiration, which requires a good supply of oxygen
  • Compost bins have holes in the walls to allow oxygen to enter
  • Gardeners mix the compost regularly to increase oxygen supply
• Anaerobic decay


  Decomposition that occurs in the absence of oxygen, producing a mixture of gases including methane
• Small-scale biogas generators use plant materials or animal manure to produce biogas under anaerobic conditions
• Decomposers produce biogas under anaerobic conditions