Cycling in ecosystems

• Decay cycle 


  CO2 and Minerals

  1. plants and animals die
  2. after dying they decompose by decomposers and detritivores
  3. all organisms that carry out decay respire (decomposers and detritivores)
  4. respiration releases CO2 back into the air
  5. CO2 goes into the plants via the stomata and is used for photosynthesis
  6. decomposers that feed off dead plant material respire and release carbon dioxide/water and breakdown material into absorbable nutrients which enter plants through roots
• Water cycle

  Water

  1. Evaporation of water from sunlight into water vapour
  2. water vapour rises via transpiration
  3. water vapor condenses and forms clouds
  4. Precipitation - rain, snow, hail, etc
  5. water falls back to ground
  6. Percolate - water trickles through gaps in rocks
  7. feeds into rivers to the sea
• Carbon cycle

  Natural and unnatural

  1. carbon dioxide in air is taken in by plants via photosynthesis
  2. carbon becomes carbon compounds which is eaten by animals
  3. animals respire and release CO2
  4. plants and animals die
  5. decomposers and detritivores respire and release CO2 - In right conditions
  6. IN WRONG CONDITIONS - animals and plants forms fossils forming fossil fuels ( over millions of years )
  7. fossil fuels are burnt - combustion (unnatural)
  8. releases CO2 into the air
• Carbon sink : where large amounts of carbon is locked up E.g. in rocks, oceans, air
• Detritivore - dead matter

  Detritivores - feed on dead matter

  Nitrates - aid the process of decay