nutrient cycling

• Carbon, oxygen, nitrogen and water circulation in the environment


  1. Change from one form to another

  2. Stay in roughly the same proportions within ecosystems
• Energy does not cycle, instead it flows through ecosystems in a straight line
• All the energy is lost at the end
• All living things eventually die
• What happens to the bodies of dead living things

  1. Death and decay

  2. Decomposition by microbes

  3. Microbes obtain energy and materials to grow and reproduce
• Decomposers


  • Worms
  • Slugs
• Importance of decomposers

  • Eat biomass that other things cannot use
  • Return materials, which plants need, back to the soil
  • Allow the elements of life to be used again and again (recycling)
• There are consumers that feed only on the dead remains of others
• Role of consumers that feed on dead remains

  • Prevent the environment from getting cluttered up with dead bodies and waste
  • Help to recycle materials