Carbon Cycle

Question 1

Tell me everything you know art carbon

Answer 1

element

found in all living things - NO CARBON = NO LIFE
plus in non-living things (e.g. ocean)

4 electrons in outer shell, therefore, capable of bonding wt almost any other element

constantly moving - doesn’t stay in 1 place long
= CARBON CYCLE

Question 2

What are some carbon stores?

Answer 2

plants

consumers

dead matter

fossils + fossil fuels (peat, coal, oil)

atmosphere

ocean

Question 3

How do plants utilise carbon?

Answer 3

plants use CO2 from atmosphere to photosynthesis

therefore, becomes part of plant (stored food)

light + CO2 + H2O ——-> glucose + O2

Question 4

How does carbon reach consumers?

Answer 4

when organisms consume plants, carbon is then in & becomes part of their body

plants = foundation of food chain
therefore, rest will receive it

when organisms die - carbon moved through decomposition (carbon released into atmosphere) or not fully decomposed (fossil fuels)

Question 5

What are the process involved in the carbon cycle?

Answer 5

combustion

fossilisation

consumption

respiration

egestion

death

incomplete decomposition

photosynthesis

Question 6

Draw the carbon cycle

Answer 6

wWeeEELll dDoonneE SssiiisSsyYy!!!

YOU GOT THIS BOOOOO!!!! IIIII llllOOOOVVVEE EYYOOOUU!!

Question 7

How is carbon incorporated in aquatic ecosystems?

Answer 7

carbon in form CO2 will dissolve wt H2O
= carbonic acid (H2CO3)

dissolved CO2 & H + CO3 ions absorbed by autotrophs

H+ ions increases acidity / decrease pH

PROCESS:
CO2 + H2O —> H2CO3 —> H+ + (HCO3)-

Question 8

What are the main conditions for peat formation?

Answer 8

organic matter not fully decomposed

acidic / anaerobic conditions

water-logged soils

note: extremely effective carbon sink (550 Gt of world’s carbon), burns easily

Question 9

How is peat formed?

Answer 9

organic matter digested by saprotrophs in soil

saprotrophs assimilate some carbon for growth & release CO2 in aerobic respiration (needs O)

waterlogged soils are an anaerobic environment

therefore, saprotrophs & methanogens are inhibited

organic matter partially decomposed (therefore adds to acidity & previous step)

Large quantities of partially decomposed matter build up

compression = PEAT!

Question 10

How are other fossil fuels formed?

Answer 10

e.g. petroleum & natural gas:

300 -400 mil. years ago - sea animal & plants die & curried @ sea floor

50 - 100 mill. years ago - remains buried deeper by enormous heat & pressure (due to sand & silt) turned into oil & gas

today - drill through layers of silt, sand, rock to reach rock formations wt oil & gas deposits

Question 11

How are fossils and limestone formed?

Answer 11

some animals recreate calcium carbonate (CaCO3)

• why? protection (e.g. mollusc shells, hard coral exoskeleton)

death = soft body parts decompose + CaCO3 remains to form deposits

deposits buried & compressed to form limestone
imprints of hard body parts in rocks = fossils

Question 12

How is CO2 produced by combustion?

Answer 12

biomass & fossilised organic matter heat to ignition temp. + O2 = COMBUSTION!!

Question 13

How is methane incorporated into carbon cycle?

Answer 13

CH4 produced by:
organic matter + anaerobic conditions + methanogenic archaeans

e. g. wetlands - H2O covers soil = anaerobic cold. –> methanogenic achaeans = abundant —> produce CH4 by decomposing organic matter —-> high levels of CH4 in soil = some diffused wt atmosphere
e. g. ruminants —> methanogens —> CH4 in atmosphere

then released into atmosphere

in atmosphere:
CH4 —-oxidation by hydroxyl radicals—-> CO2 + H2O
(METHANE REMOVAL!!)

Question 14

How is carbon measured?

Answer 14

not possible to measure size of carbon sinks & fluxes btw them

estimates based on diff. measurements often published wt large uncertainties as a result