Carbon Cycle Content Flashcards
What are the three forms of carbon in the carbon cycle?
Inorganic
Organic
Gaseous
What is Inorganic carbon?
Found in rocks as bicarbonates and carbonates
What is organic carbon?
Found in plant material and living organisms
What is gaseous carbon?
Found as CO2 and CH4 (methane)
What are the three types of carbon stores?
Terrestrial
Oceanic
Atmospheric
What is a carbon flux?
The movement of carbon between stores
What is a carbon sink?
A Carbon sink is any store which takes more carbon than it emits
What is a carbon source?
Any store that emits more carbon than it stores
What is carbon Sequestration?
The transfer of carbon from the atmosphere to other stores and can be natural and artificial
What are the main carbon stores, in order of magnitude?
Marine sediments and sedimentary rocks
Oceans
Fossil fuel deposits
Soil organic matter
Atmospheric
Terrestrial plants
What is the main store of carbon?
The lithosphere
What happens when you remove CO2 from the atmosphere
Plants are sequestering carbon and reducing the potential impacts of climate change
What is respiration?
Respiration occurs when plants and animals convert oxygen and glucose into energy
What happens to photosynthesis during the day?
Plants photosynthesise more during the day absorbing significantly more CO2 than they emit
What happens to photosynthesis during the night?
Plants do not photosynthesise at all during the night but respire releasing more CO2 than they absorb
What is combustion?
When fossil fuels and organic matter such as trees are burnt, they emit CO2 into the atmosphere
What is decomposition?
When living organisms die, they are broken down by decomposes which respite, returning CO2 into the atmosphere
What is the quickest cycle?
Is completed in seconds as plants absorb carbon for photosynthesis and then they release carbon when they respire.
How long can dead organic material hold Carbon for?
Can hold it for hundreds of years
What is the largest carbon stores?
Oceans. They are 50 times larger than the atmosphere with 93% of l CO2 stored in algae, plants and coral.
How do small changes to oceanic carbon levels lead to significant global impacts?
It affects the thermohaline system and the store of carbon in the ocean
Explain the phytoplankton stage in the biological carbon pump?
Phytoplankton photosynthesis, they take in carbon and turn it into atmospheric carbon. When they get eaten, carbon is passed through the food chain. CO2 is also released back into the water as these organisms respire.
Explain the animal shells in the carbon cycle?
Some organisms like plankton sequester CO2 turning the carbon into their hard outer shells and inner skeletons. When these organisms die, some of their shells dissolve into the ocean water meaning the carbon becomes part of the deep ocean currents.
Describe the process of sedimentation?
Any dead organisms which sink to the seafloor become buried and compressed, eventually forming limestone sediments. Over a long time period these can turn into fossil fuels (fossilisation)
What happens when CO2 is dissolved into the ocean?
This process occurs on the surface of the oceans where CO2 reacts with water to form carbonic acid. As the concentrations of CO2 in the atmosphere increase, oceans absorb more CO2 causing them to be more acidic.
Explain ocean acidification
The increased concentration of CO2 in the ocean creates more carbonic acid. This has long lasting effects. Such as coral reef bleeching
What happens in the physical pump?
1) these move carbon compounds to different parts of the ocean in downwelling and upwelling currents
2) downwelling occurs in parts of the ocean where cold, denser water sinks
3) these currents bring dissolved bring dissolved carbon dioxide down to the deep ocean.
4) once there, it moves in slow-moving deep ocean currents, staying there for hundreds of years
5) eventually, these deep ocean currents, part of the thermohaline, circulation, return to the surface by upwelling
6) the cold deep ocean water warms as it rises towards the ocean surface and some of the dissolved carbon dioxide is released back into the atmosphere
Explain the carbonate pumps
1) These form sediments from dead organisms that fall to the ocean floor, especially the hard outer shells and skeletons of fish, crustaceans and corals, all rich in calcium carbonate
What is terrestrial sequestering?
Terrestrial primary producers sequester carbon during photosynthesis; some of this carbon is returned to the atmosphere during respiration by consumer organisms
Explain the process of Terrestrial sequestering?
1) (primary producers in an ecosystem) sequester carbon out of the atmosphere during photosynthesis. This means carbon enters the food chains
2) when animals consume plant matte, the carbon is sequestered in the plant and becomes part of their fat and protein. Respiration returns some of the carbon back to the atmosphere
3) waste from animals is eaten by micro-organisms and detritus feeders
4) as a consequence, carbon becomes part of these creatures. When plants and animals die carbon is released into the soil
