The Carbon Cycle

• The Carbon Cycle:

  • Nutrients such as carbon and nitrogen are not endless resources, and so, they need to be recycled in order to allow new organisms to be made and grow 
  • Carbon is taken out of the atmosphere in the form of carbon dioxide by plants to be used for photosynthesis
  • It is passed on to animals (and microorganisms) via feeding
  • It is returned to the atmosphere in the form of carbon dioxide by plants, animals and microorganisms as a result of respiration
• The Carbon Cycle:

  • If animals and plants die in conditions where decomposing microorganisms are not present the carbon in their bodies can be converted, over millions of years and significant pressure, into fossil fuels
  • When fossil fuels are burned (the process is known as combustion), the carbon combines with oxygen and carbon dioxide is released into the atmosphere
  • Increased use of fossil fuels is contributing to an increase in the carbon dioxide content of the atmosphere...
• • This problem is exacerbated by the fact that in many areas of the world, deforestation is taking place for land (for livestock grazing) rather than for the trees themselves
  • As such, trees are burnt down, releasing yet more carbon dioxide into the atmosphere
  • In addition, mass deforestation is reducing the amount of producers available to take carbon dioxide out of the atmosphere by photosynthesis
• The carbon cycle:

  
• The carbon cycle:

  
• The importance of the carbon cycle:

  • Carbon is a component of all organic molecules, many of which are essential for life on earth, such as glucose
  • The carbon cycle is a key process which allows the movement of carbon between global reservoirs including the
  • Atmosphere
  • Biomass
  • Oceans
  • Soil
• • The balance of carbon between these reservoirs is fundamental due to the role that carbon plays in sustaining life
  • If the balance is disrupted, somewhere along the way organisms will suffer
  • Global warming is a large scale example of the effect which may be seen if the global carbon balance is disrupted