1.5 The Carbon Cycle Flashcards
Where is carbon found?
organic and inorganic stores
rocks, gases and fossil fuels
Where is carbon found in the lithosphere?
over 99% of carbon on earth is stored in sedimentary rock such as limestone
0.004% of the carbon on earth is stored in fossil fuels such as coil and oil in the lithosphere
Where is carbon found in the hydrosphere?
CO2 is dissolved in rivers and lakes
oceans are the second largest carbon stores on earth containing 0.04% of the earths carbon, the majority of the carbon is deep in the ocean in the form of dissolved inorganic carbon
some is at the oceans surface where it is exchanged with the atmosphere
Where is carbon found in the biosphere?
carbon is stored in the tissues of living organisms, it is transferred to the soil when living organisms die and decay
contains about 0.004% of the earths total carbon
Where is carbon found in the atmosphere?
carbon is stored as carbon dioxide and in similar quantities as methane ion the atmosphere
the atmosphere contains about 0.001% of the earths carbon
Where is carbon found in the cryosphere?
less than 0.01% of earths carbon
most of it is located in the soil in areas of permafrost where decomposing plants and animals have been frozen into the ground
Is the carbon cycle an open or a closed system?
closed system, inputs and outputs of energy but the amount of carbon remains the same
Why do carbon stores change in size over time?
because of carbon flows
Explain photosynthesis with reference to the change in carbon stores over time
- photosynthesis transfers carbon stored in the atmosphere to biomass
- plants and phytoplankton use energy from the sun to change CO2 and water into glucose and oxygen, this enables plants to grow
- carbon is passed through the food chain and released through respiration and decomposition
Explain combustion with reference to the change in carbon stores over time
- combustion transfers carbon stored in living dead or decomposed biomass to the atmosphere by burning
- wildfires cause carbon flow.
Explain ocean up take and loss with reference to the change in carbon stores over time
- CO2 is directly dissolved from the atmosphere into the ocean, it is also transferred to the oceans when it is taken up by organisms that live in them
- carbon is also transferred from the ocean to the atmosphere when carbon-rich water from deep in the oceans rises to the surface and releases CO2
Explain sequestration with reference to the change in carbon stores over time
- carbon from the atmosphere can be sequestrated in sedimentary rocks or as fossil fuels, rocks and fossil fuels form over millions of years when dead and plant material in the ocean falls to the floor and is compacted
- carbon in fossil fuels is sequestrated until we burn them
Explain respiration with reference to the change in carbon stores over time
- respiration transfers carbon from living organisms to the atmosphere
- plants and animals break down glucose for energy, releasing CO2 and methane in the process.
Explain decompostiton with reference to the change in carbon stores over time
- decomposition transfers carbon from dead biomass to the atmosphere and the soil
- after death bacteria and fungi break organisms down, CO2 and methane are released
- some carbon is transferred to the soil in the form of hummus
Explain weathering with reference to the change in carbon stores over time
- chemical weathering transfers carbon from the atmosphere to the hydrosphere and biosphere
- atmospheric carbon reacts with water vapour to form acid rain, when this acid rain falls onto the rocks,a chemical reaction occurs that dissolves the rocks. the molecules resulting from this reaction may be washed into the sea, here they react with C02 dissolved within the water to form calcium carbonate, which is used by sea creatures to make shells
