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geography alevel edexcel Carbon cycle?

I actually cried its taken me 2 hours and I still don't understand the first lesson we had on the carbon cycle and my exam is soon.

I understand there are 3 stores, terrestrial being the largest because of sedimentary rocks.

I don't know if I need to know all the processes in detail and what are fluxes, geological, biological and chemical processes all sound the same to me and they're all detailed.

I also don't understand how to categorise all the information.
okay i really struggle with the carbon cycle to so ima try my best and if its not great also check physics and maths tutor online bc they have amazing resources
4 major stores are the lithosphere, hydrosphere, biosphere and atmosphere.
lithosphere
- carbon is stored in organic (eg litter, organic matter and humic substances in soil) and inorganic (eg fossil fuels and carbonate based sedimentary deposits) forms
- lithosphere includes crust and upper mantle of the earth
- carbon in lithosphere is distributed between marine sediments and sedimentary rocks, soil organic matter, fossil fuel deposits and peat - in order of most to least
hydrosphere
- oceanic stores divided into 3: the surface layer (where sunlight penetrates to allow for photosynthesis), the twilight zone and deepest layer and living organic matter (fish, plankton and bacteria) and dissolved organic matter
- cells, shells and other parts of dead organisms sink into deep water and decay releasing carbon dioxide.
material that sinks straight to the bottom produces layers of carbon rich sediments
biosphere
- total sum of all living matter (terrestrial not oceanic dont worry)
- distribution differs between ecosystems
- so main stores include: living vegetation (plants) where 19% of global carbon is, plant litter (fresh and undecomposed plant debris), soil humus (not the food but the remains of decomposed plant litter that is eaten by composers that distribute it in the soil after), peat (partially decayed vag or organic matter thats unique due to low oxygen anerobic conditions to slow down decay),and animals (not that important in storage but very important when considering the movement)
atmosphere
- i understand little to nothing but cows fart and methane goes to atmosphere so sorry abt that

i hope that helps and ill try and find more about what you will need to know in a moment
okay so the movement of carbon is broken down into geology, photo synthesis, respiration, decomposition, oceanic carbon pumps, combustion (and biomass combustion), volcanic activity, hydrocarbon extraction and burning, farming practices and carbon sequestration.
and trust me its a lot but if you balance your time right and focus on understanding and applying the content it will be far easier to recall info.

geological
- where carbon cycle interacts with rock cycle
- when CO2 is removed from atmosphere it is dissolved in water to form carbonic acid and as its slightly acidic it reacts with minerals on the earths surface (woo chemical weathering)
- blah blah the water is then washed away in streams and rivers and stuff how boring and eventually into the ocean when they become calcium carbonate
- calcium carbonate used for building shells or skeletons
- tectonic forces essentially swallow up sea floor during subduction and then vomit it bacj out again at hot springs or volcanoes how fun is that
- fun fact the volcanoes and hot springs release carbon back into the atmosphere starting the cycle again
photo synthesis
- CO2+ H2O + sunlight ----> carbohydrate (glucose)+ oxygen
- essentially know the equation and dont worry abt the rest
respiration
- the opposite equation to photosynthesis minus the sunlight
decomposition
- physical, chemical and biological mechanisms that make organic matter into stable forms (unluckily our brains struggle to make us stable so now we cry over everything including the carbon cycle, dont worry weve all been there)
- leaching and water transport is physical
- oxidation and condensation is chemical
- feeding and digestion with the help of enzymes is biological
- decomposers break down cells and tissues of dead organisms into small biomolecules and then even smaller and smaller and smaller until they reach atoms
- basically decomposition said we will recycle our elements (specifically: carbon, hydrogen, oxygen, nitrogen, phosphorus, sulphur and magnesium)
oceanic carbon pumps ( i dont like this one)
- water dissovles CO2 and the amount that is dissovlable correlates to the temp of water (the warmer the more carbon dissolved)
- living things in ocean also move all of that lovely carbon around bc theyre so nice like that
combustion
- uh fire?
- bio mass combustion is burning living and dead vegetation so thats cute
volcanic activity
- like i said earlier carbon sucked up when subduction occurs and released via volcano
hydrocarbon extraction and burning
- i know next to nothing on this icl
- dead plants and animals become fossil fuels
- that is my only understanding im afraid
farming practices
- land use change- CO2 from changing land use eg deforestation is like 30% of anthropogenic CO2 emmisions
- deforestation- tree cut down/ burnt = release of carbon as burnt/decomposing
- urban growth - transport, industry and domestic use
carbon sequestration
- geological sequestration- CO2 captured at source and injected in liquid form to store under ground (depleted oil or gas reservoirs, coal, deep ocean etc)
- terrestrial/ biological sequestration - use of plants to capture CO2 to store as carbon in stems roots and soil

hopefully that covers the right stuff in a more condensed helpful way:smile:
Original post by t0897
I actually cried its taken me 2 hours and I still don't understand the first lesson we had on the carbon cycle and my exam is soon.

I understand there are 3 stores, terrestrial being the largest because of sedimentary rocks.

I don't know if I need to know all the processes in detail and what are fluxes, geological, biological and chemical processes all sound the same to me and they're all detailed.

I also don't understand how to categorise all the information.


okay im silly and didnt read the edexcell bit so what ive written is for AQA but from checking the spec most of which is still applicable for you
Reply 4
Original post by crispy._.squid
okay im silly and didnt read the edexcell bit so what ive written is for AQA but from checking the spec most of which is still applicable for you

THANK YOU so muchhhh
You really wrote a lot out and helped to differentiate between all the possible processes. I learnt 3 for each because in my class book we only went through a few and the ones on the edexcel spec. The difference between chemical and geological still confuse me, is the chemical weathering a chemical process or geological because it dissolves minerals in the rock? and why would volcanic outgassing be geological?
OK so, a bit of extra although you have some good stuff to go on...



"I understand there are 3 stores, terrestrial being the largest because of sedimentary rocks."

Simplified, this is right... but I don't think enough.
There are 6 main stores with different amounts (quantified in gigatonnes) of carbon
1) LITHOSPHERE - over 100,000 gigatonnes (this is sedimentary rocks like you say, and fossil fuel deposits)
2) HYDROSPHERE - 40,000 (carbon absorbed and stored by ocean)
3) PEDOSPHERE - 1,500 (within the soil)
4) CRYOSPHERE - 1,700 gigatonnes (within permafrost soils for example)
5) ATMOSPHERE - 800 gigatonnes
6) BIOSPHERE - 560 gigatonnes (within plant litter, soil humus and LIVING vegetation)



I don't know if I need to know all the processes in detail and what are fluxes, geological, biological and chemical processes all sound the same to me and they're all detailed.

A flux is the amount of carbon exchanged between Earth's carbon pools and is typically measured in units of gigatonnes of carbon per year (GtC/yr).
I STRUGGLE W CARBON ALSO. Use physics maths tutor and Weebly alevel geography. And watch videos and videos
Reply 7
Original post by sophiesharp765
OK so, a bit of extra although you have some good stuff to go on...



"I understand there are 3 stores, terrestrial being the largest because of sedimentary rocks."

Simplified, this is right... but I don't think enough.
There are 6 main stores with different amounts (quantified in gigatonnes) of carbon
1) LITHOSPHERE - over 100,000 gigatonnes (this is sedimentary rocks like you say, and fossil fuel deposits)
2) HYDROSPHERE - 40,000 (carbon absorbed and stored by ocean)
3) PEDOSPHERE - 1,500 (within the soil)
4) CRYOSPHERE - 1,700 gigatonnes (within permafrost soils for example)
5) ATMOSPHERE - 800 gigatonnes
6) BIOSPHERE - 560 gigatonnes (within plant litter, soil humus and LIVING vegetation)



I don't know if I need to know all the processes in detail and what are fluxes, geological, biological and chemical processes all sound the same to me and they're all detailed.

A flux is the amount of carbon exchanged between Earth's carbon pools and is typically measured in units of gigatonnes of carbon per year (GtC/yr).

my teacher never taught us about these 6 main stores we just learnt about the terrestrial store, atmosphere and oceanic?
Reply 8
Original post by mystudentlife
I STRUGGLE W CARBON ALSO. Use physics maths tutor and Weebly alevel geography. And watch videos and videos

i looked at the PMT notes, the notes don't correspond to what we were taught in lessons, it's making me confused.
Original post by t0897
i looked at the PMT notes, the notes don't correspond to what we were taught in lessons, it's making me confused.


Did u look at edexcel notes, also have u looked at the other website yet. I feel like it’s more useful and simpler to understand. Its only for edexcel I think.


Use snap revise to go over the main points thy have videos for the carbon cycle and explain the main processes.

Also what year r u in?
(edited 2 years ago)
Reply 10
Original post by mystudentlife
Did u look at edexcel notes, also have u looked at the other website yet. I feel like it’s more useful and simpler to understand. Its only for edexcel I think.


Use snap revise to go over the main points thy have videos for the carbon cycle and explain the main processes.

Also what year r u in?

yh i did the edexcel notes, I emailed my teacher saying what we were learnt in lesson doesn't correspond to those notes etc.
I checked the weebly website it says the page isn't found
I'm in year 13.... I neglected the carbon cycle while it was taught online and now I am feeling the consequences of my actions
Original post by t0897
yh i did the edexcel notes, I emailed my teacher saying what we were learnt in lesson doesn't correspond to those notes etc.
I checked the weebly website it says the page isn't found
I'm in year 13.... I neglected the carbon cycle while it was taught online and now I am feeling the consequences of my actions


https://geographyrevisionalevel.weebly.com/

Here’s the weebly website


How many lessons have u had for carbon so far?
Reply 12
Original post by mystudentlife
https://geographyrevisionalevel.weebly.com/

Here’s the weebly website


How many lessons have u had for carbon so far?

we finished it last year
I spoke to my friend she said with edexcel there might be different versions like A and B because our teacher told us we do one that not a lot of people do idk
Reply 13
Original post by mystudentlife
https://geographyrevisionalevel.weebly.com/

Here’s the weebly website


How many lessons have u had for carbon so far?

the link to the carbon cycle doesnt work for me but I appreciate it
https://geographyrevisionalevel.weebly.com/1a-carbon-cycle-stores-an.html
Original post by t0897
we finished it last year
I spoke to my friend she said with edexcel there might be different versions like A and B because our teacher told us we do one that not a lot of people do idk



Lisn u just gotta do anyrhing to understand it. Force urself. Have u got the text books? Read them again and again draw diagrams. Watch videos jus any videos that may help
Reply 15
Original post by mystudentlife
Lisn u just gotta do anyrhing to understand it. Force urself. Have u got the text books? Read them again and again draw diagrams. Watch videos jus any videos that may help

I've done that and simplified it and will recap it this morning and learn the next few lessons, when I return back to school we have a few lessons before the exam so I'll ask him to go over it, he's a really good teacher so I'm sure he will explain it again

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