Carbon Cycle (4.3)
SECTION LINKS: |
Notes & Review:Ecology NotesEcology Review Game |
The Carbon Cycle
|
The Carbon Cycle Consists of the release of carbon and it's uptake back into the environment.
|
|
|
Carbon Fluxes
|
Carbon Sinks: Carbon is constantly exchanged between the earth and the atmosphere. At different times of the year more carbon is present in the atmosphere than others. Places that absorb a lot of carbon are referred to as "Carbon sinks," these include the ocean, the atmosphere, biotic organisms and the earths surface itself.
|
Carbon Flux: A carbon flux is the amount of carbon exchanged between earths "pools" or "sinks" of carbon. Fluxes are expressed as a rate (units per time) and are dependent upon the carbon sinks & the exchange rate of the sinks with the atmosphere.
These sinks include four spheres:
When the exchange rate into the atomosphere is greater than the amount of carbon sequestration into the earth, this is where many are concerned about the environmental impacts of it. Environmentalists often talk about sequestering carbon even more so than nature does for us in order to slow down climate change. |
|
Methanogenesis
Methanogenesis is the production of methane gas from organic matter in anaerobic (without oxygen) conditions (usually through archean prokaryotes). It is the final stage of decomposition of organic matter. It contributes to the Carbon Cycle by it's ability to trap heat as a greenhouse gase AND by it's conversion to CO2 in the atmosphere
|
Peat, Fossil Fuels, and Limestone Formation
PeatPeat forms when plant material (usually mosses, seges, and shrubs) is not fully broken down. As it accumulates, water is retained in the soil causing the soil to become acidic.
|
Fossil FuelsCoal formed when compressed (pressured) and heated peat buried under sediments
Oil and Natural Gas formed from partially decomposed material is compressed and heated under mud in oceans and lakes usually in anaerobic (no oxygen) conditions
|
LImestone
Limestone is built from the shells of the Mollusca phylum AND hard corals that build reefs using their exoskeletons
However, in basic or stable pH environments, when the animals die the hard parts of the animal (shells) can become fossilized |