WATER AND CARBON Pt3 - The Carbon Cycle Flashcards
What are the 2 types of carbon and what do they mean?
- Organic
- the carbon atoms + molecules - Inorganic
- trees and living organisms
What are the 4 main forms of carbon atoms?
- Carbon dioxide
- gas in atmosphere, soils and oceans - Methane
- atmosphere, soils, oceans and sedimentary rock - Hydrocarbons
- solid, liquid, gas in sedimentary rock - Biomolecules
- complex carbons produced in living organisms
Describe how carbon occurred on the planet > origin of carbon
- stores in mantle released at constructive and destructive plate boundaries
- dissolved in oceans
- decaying organisms
- bound in carbon rocks
- in atmosphere
How and what is carbon measured in?
1 gigaton of carbon (GtC0 > 1 bil tonnes
Movement of carbon measured in GtC/year
Estimation of amount in billions of metric tones of carbon in each store
1. Marine sediments and sedimentary rock
2. Oceans
3. Fossil fuel deposits
4. Soil organic material
5. Atmosphere
6. Terrestrial plants
- Marine sediments and sedimentary rock > 100,000
- Oceans > 38,000
- Fossil fuel deposits > 4,000
- Soil organic matter >1,500
- Atmosphere > 750
- Terrestrial plants > 560
What are the 4 main overriding stores of carbon which encompass all other stores?
- Lithosphere
- Hydrosphere
- Biosphere
- Atmosphere
THE LITHOSPHERE
- What does this include
- Inorganic or organic
- What is the distribution of this store
- Crust, upper mantle, uppermost layer of soil (pedosphere)
- Organic and inorganic
- 100 mil GtC marine sediment and sedimentary rock
- 1,500 GtC organic soil matter
- 4,100 GtC fossil fuel deposits
- 250 GtC peat > undecayed organic matter
THE HYDROSPHERE
- What does this include
- Inorganic or organic
- What is the distribution of the store
- Describe how carbonate rocks form in this environment
- all water and oceans
- primarily organic
- 900 GtC surface layer > sun penetrates + allows photosynthesis (EUPHOTIC ZONE)
- 37,000 immediate and deep layers (TWILIGHT ZONE)
- 30 GtC living organic matter
- 700 GtC dissolved organic matter
- organisms die > co2 released in decay
- material sinks to bottom to form carbon rich sediments
- over millions of years carbonate rocks form
THE BIOSPHERE
(sum 3,170 GtC)
1. what does this include
2. inorganic or organic
3. what is the distribution of the store
4. what is plant litter
5. what is soil humus
6. living vegetation % in russia boreal and temperate forests compared to amazon basin
7. how does the ratio of biomass and soil differ between forests and tropical rainforests
- the whole of the natural environment
- mostly organic
- 19% of global store in plants
- amount of carbon in biomass of dry weight = 35-65%
- 1/2 carbon forests in high latitudes and 1/3 in low latitudes
- soil carbon > 2,500 GtC»_space; organic (1,550)»_space; inorganic (950)
- fresh undecomposed plant debris > type is controlled by ecosystem type
- substance left after most the organic matter has decomposed
- russia (25%) amazon (30%)
- rainforests > biomass (31%) soil (69%). TRF 50/50
THE ATMOSPHERE
1. levels of carbon during + when
- highest
- lowest
- current
2. impact of human activities
3. how and where carbon in ppm is measured > since when
4. time scale of atmospheric co2 in 1958 march, 2013 may, 2015 feb and what the rate of incr is
- 7,700 ppm (Cambrian 500 mil years ago)
- 180ppm (Quaternqry glacial period 2 mil years ago)
- 720-800 ppm > 0.04% of atmosphere
- levels highest in last 800,000 years
- measured MLO on Hawaii since 1958 due to undisturbed air, remote location and limited influence of vegetation and humans
- 1958 march > 317.7 ppm
2013 may > 400 ppm > 2ppm per year
2015 > 400.3
what are the billions of tonnes of carbon and what that is as a percentage of the following carbon stores
first 3 are short term rate of movement and the second 3 are the long term rate of movement
1. biosphere
2. atmosphere
3. pedosphere
- fossil fuels
- hydrosphere
- lithosphere
- atmosphere
560 and 0.0012% - atmosphere
750 and 0.0017% - pedosphere
? and 0.0031% - fossil fuels
4,000 and 0.004% - hydrosphere
38,000 and 0.038% - lithosphere
100,000 (crust only) and >99.9%
what are the 4 geological components involved in the movement of carbon in the lithosphere + describe them
- weathering
- CO2 removed from atmosphere when dissolved in water (carbonic acid), weak acid reaches earth + reacts with minerals and dissolves them - burial
- marine organisms die, sink to the bottom, burial, sedimentary limestone - subduction
- tectonic uplift can expose buried limestone and tectonic movements can also push carbonaceous seafloor deposits deep into the earth - volcanic eruptions
- when erupts, carbon melts and is released
what are the 5 biological components involved in the movement of carbon + describe them
- photosynthesis
CO2 + water»_space;» CH2O + O2 - respiration
O2 + CH2O»_space;» H2O + CO
however respiration and photosynthesis are unbalanced > not all organic matter oxidised so more CO2 removed and more O2 added - decomposition
- key physical mechanisms > fragmentation, leaching and transport in water
- chemical transformations > oxidisation and condensation
- biological mechanisms > feeding, digestion aided by catalytic effect (enzymes)
- decomposition process by decomposes > ensures recycling of important elements e.g. nitrogen + phosphorus - oceanic carbon pumps
water able to dissolve CO2 > neg correlation of water temp and amount of CO2 that can be dissolved > vertical deep mixing - biomass combustion (wildfires)
when organic material is reacted (burned) in presence of O2
pollutant molecules also formed e.g. lead, ground level ozone, nitrogen dioxide, carbon monoxide, sulfur dioxide, particulate matter
where does wildfire biomass combustion mostly happen (ecosystem and example)
- boreal forests > alaska + china
- savannah grassland > africa
- TRF > brazil, colombia
- temperate forests > US and western europe
- agricultural waste > “. “
what is the lifecycle of a tree linked to the carbon cycle due to wildfire biomass combustion + key statistic about wildfires
- tree die after severe fire, allows new growth, 10-20% of carbon emitted into atmosphere
- old trees decompose + emit carbon > balance determines sink or source
- incr regularity of fires > more changes to carbon balance
every year 3-4 mil km^3 burnt + 1 billion tonnes of carbon released