Processes involved in the carbon cycle are:
Photosynthesis – plants absorb CO2 from the atmosphere and convert it into organic compounds. This is the only process in the carbon cycle that decreases the level of atmospheric CO2.
Feeding – moves carbon in biological molecules along food chains.
Respiration – when living organisms (plants, animals and decomposers (bacteria and fungi)) respire they release CO2 into the atmosphere.
Fossilisation – in some conditions, dead organisms may not decay, Instead, they get compressed over millions of years and form fossil fuels (coal, oil or gas) or carbon stores such as limestone.
Weathering – acid rain can dissolve limestone, releasing CO2.
Combustion – when fossil fuels are burned, CO2 is released into the atmosphere.
Excretion – carbon compounds are excreted in urine. This material is then broken down by decomposers.
Egestion – carbon is egested in faeces. This material is then broken down by decomposers.
Decomposition – carbon compounds in dead organisms, urine and faeces are broken down by decomposers (bacteria or fungi).
Describe how the carbohydrates in the dead leaves of eucalypt trees would be recycled by the activity of detritivores and microorganisms.
Explain how the felling and burning of trees on a large scale could affect the concentration of carbon dioxide in the atmosphere.