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I think this is a neat idea but have one question. I'm not a chemist but am curious what happens to all that carbon after it's taken in by the tree. Does that

by mal10c 7y ago

I think this is a neat idea but have one question. I'm not a chemist but am curious what happens to all that carbon after it's taken in by the tree. Does that carbon become something else? Or does it just kind of hang out in the tree until the tree dies? Once the tree dies, does all that carbon just go back to the atmosphere again? Thanks for any insight!

dcre 7y ago
It is part of the wood itself. Apparently wood is about half carbon. All known living things are made of carbon. https://en.wikipedia.org/wiki/Wood#Chemistry_of_wood https://en.wikipedia.org/wiki/Wood#Chemistry_of_wood https://en.wikipedia.org/wiki/Carbon-based_life https://en.wikipedia.org/wiki/Carbon-based_life
joshAg 7y ago
The carbon becomes part of the wood of the tree. After the tree dies, it would only go back into the atmosphere if the trunk was burned.
- eitland 7y ago
  > After the tree dies, it would only go back into the atmosphere if the trunk was burned. To nitpick: or if it decomposes in other ways.
  - wjnc 7y ago
    And what if we bury it? Can we do landfills with the trunks of these trees, like filling up old brown coal mines? This was something that I was thinking about while driving past a few former mines in Germany. Great places to fill up with decomposables. At a certain point the top layer will stop the bottom layers CO2 from leaking, I expect?
    - Symmetry 7y ago
      If you bury it you might be able to stop oxygen from getting in and turning into CO2, at least with any speed. But if water gets in you can still have methanogen bacteria come in and turn the wood into methane. Which you might be able to capture and sell and displace methane mined out of the ground but that isn't the same as locking it away forever. This process is why you have methane production in swamps and conventional landfills.
    - thinkcontext 7y ago
      There are a lot of things wrong with this idea. - Shallow burying the wood would not stop emissions from escaping into the atmosphere. Doing so would deprive it of oxygen which would cause the production of methane which is even worse than co2 - Wood is way less dense than coal so even if the idea worked you would only be able to store a fraction of the amount of co2 - Its hard to imagine the sheer scale of collecting all the wood to ship back to the mines. As mentioned wood is much less dense than coal so the effort to ship the wood to coal mines would be much more difficult than shipping the coal out of the mines. Not to mention that the wood would be coming from a much wider area. There are ideas about burning wood to produce electricity, capturing the CO2 exhaust and pumping that deep underground. The concept is called Bio-Energy with Carbon Capture and Storage (BECCS).
olliej 7y ago
The carbon is essentially the entirety of the tree itself
deleted 7y ago
[deleted]
deleted 7y ago
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Expez 7y ago
Yes, it's only captured until the tree dies. After that the tree rots etc and carbon is released again. The clue to net carbon capture is to plant new forests and make sure the forest stays alive. While the forest lives, all the CO2 is safely sequestered.
LeoPanthera 7y ago
It turns into wood! It's actually pretty amazing. I always though the physical substance of wood came out of the ground, through the roots, but in fact wood is made almost exclusively out of air. Trees are frozen air.
- beat 7y ago
  As an aside, that's also how we lose weight! When we burn away fat, we breathe it out.
evanb 7y ago
The carbon goes back into the atmosphere if you burn it. If you just let it decay, turn into top soil, and ultimately become entombed by the surface of the Earth it will, ultimately, suffer the fate of most of the ancient plants we today burn in their carbon-storage form: underground oil.
Spellman 7y ago
As it turns out, the vast majority of any plant is actually Carbon! That it got from the AIR!!!! I remember when my friends' brains were blown that all trees are essentially made out of "air" that got converted to wood. Technically it's the 2xCO_2 -> 2xO_2+2C and the Carbon that sticks around becomes the wood. (also insert Water and energy into that equation. Photosynthesis is crazy). And yes, if it gets burned or decomposed that carbon can get released back into the air (usually as CO2) but if you instead bury it you essentially lock it into solid form. And over years and years that becomes oil!
- twic 7y ago
  I'm really pleased to see people in this subthread being so excited about the fact that plants are made out of carbon they extract from the air. Question, though: isn't this something you learned in school?
Maximus9000 7y ago
As others have said the carbon is locked into the physical wood. When it rots or burns, that carbon is released back. However, you can hijack the process a little and keep the carbon locked away by doing things. You could use the wood as lumber or you could burn the wood in a special way which produces biochar.
dlazar 7y ago
Also not a chemist, but here's my basic understanding. The tree absorbs CO2 from the atmosphere and combines it with water (H2O) from the soil to produce more complex chemical compounds (such as carbohydrates). This process uses sunlight as the source of energy, and is better known as photosynthesis. The chemical compounds thus produced are used by the tree as structural material (the wood), or as stored energy (basically, reverting the photosynthesis reaction, aka "burning", releases the energy). If the tree matter gets consumed by animals, those animals are going to use the stored energy, and ultimately re-release the stored carbon as CO2. If the tree just dies and is allowed to decompose, bacteria and other microorganisms will do the same: they'll eat the carbohydrates that the tree produced, and they'll breathe out the resulting CO2. If the tree is burned as fuel, the CO2 gets re-emitted directly. So, to truly remove that CO2 from the atmosphere, the tree needs to be felled once it's stopped growing, and the resulting wood stored someplace where it can't be decomposed by microorganisms. Burying it is one solution to this (and this is what happened during the carboniferous era, when much of our coal and oil got created: dead trees fell in shallow swamps and were quickly buried under a layer of silt which prevented the decomposition). Again, I'm no expert, so I'm happy to stand corrected if I've made any mistakes above.
- radicalbyte 7y ago
  The easiest thing to do is to burn it into biochar and then either bury that or use it as a fertilizer on fields where it will get taken up in the soil. There are some active land management techniques which do something similar with shrubs/plants/grasses which generate an enormous amount of soil and therefore trap a lot of carbon.
  - dlazar 7y ago
    Interesting, I hadn't realized pyrolysis (used to produce biochar) does not release CO2. Seeing "pyro" (Greek for "fire") I had assumed oxidation. Sounds like a good technique for making the wood "indigestible" for microorganisms. I wonder if it's worth doing energywise, compared with just burying it somewhere.
hn_throwaway_99 7y ago
Interesting tidbit about this. The reason we have so much fossil fuel in the first place is because of what happened during the Carboniferous era. Trees evolved the capability to produce lignin, the 'woody' material in trees. However, it took millions of more years for microorganisms to evolve the ability to decompose lignin. So instead of what happens today when a tree dies and rots, the tree died and just piled up in the forest. I always think it's amazing to imagine what a forest must have looked like during the Carboniferous with all these dead trees just piled high. Trees were essentially like today's plastic: non-biodegradable refuse that stuck around for millennia. Eventually all those trees got buried and turned into fossil fuels (mostly coal). And, interestingly, this process let to huge climate change back then, too - basically the reverse of what's happening now (and at a much slower pace). Trees sucked all this carbon out of the air and reduced global temperatures by about 8C. Edit: One other note - there were of course still forest fires during the Carboniferous. It's believed they would have been incredible raging infernos with so much undecomposed combustible material.
- galangalalgol 7y ago
  so when the ability to break down plastic becomes widespread amongs organisms and they devour all the microplastics in the ocean, our co2 levels are going to skyrocket...
thinkcontext 7y ago
Many have commented about carbon becoming part of the tree however one also has to consider carbon in the soil around the tree. Plants put carbon into the ground through their roots and leaves, bark and other material that comes off of them that then feeds soil bacteria, fungi, worms, etc. Think about the soil underfoot in a mature forest is versus that under a lawn. In the forest you have soft, airy soil that teems with life and goes down for meters, whereas a lawn is compacted dirt after about a foot. There's a huge difference in stored carbon between them. Its a complex ecosystem with the plants at the center, and trees, since they have the deepest roots do the best at promoting carbon uptake. Of course, if you clearcut a forest the soil ecosystem dies and the carbon eventually comes back out of the ground.

by mal10c 7y ago

dcre 7y ago

It is part of the wood itself. Apparently wood is about half carbon. All known living things are made of carbon. https://en.wikipedia.org/wiki/Wood#Chemistry_of_wood https://en.wikipedia.org/wiki/Wood#Chemistry_of_wood https://en.wikipedia.org/wiki/Carbon-based_life https://en.wikipedia.org/wiki/Carbon-based_life

joshAg 7y ago

The carbon becomes part of the wood of the tree. After the tree dies, it would only go back into the atmosphere if the trunk was burned.

eitland 7y ago
> After the tree dies, it would only go back into the atmosphere if the trunk was burned. To nitpick: or if it decomposes in other ways.
- wjnc 7y ago
  And what if we bury it? Can we do landfills with the trunks of these trees, like filling up old brown coal mines? This was something that I was thinking about while driving past a few former mines in Germany. Great places to fill up with decomposables. At a certain point the top layer will stop the bottom layers CO2 from leaking, I expect?
  - Symmetry 7y ago
    If you bury it you might be able to stop oxygen from getting in and turning into CO2, at least with any speed. But if water gets in you can still have methanogen bacteria come in and turn the wood into methane. Which you might be able to capture and sell and displace methane mined out of the ground but that isn't the same as locking it away forever. This process is why you have methane production in swamps and conventional landfills.
  - thinkcontext 7y ago
    There are a lot of things wrong with this idea. - Shallow burying the wood would not stop emissions from escaping into the atmosphere. Doing so would deprive it of oxygen which would cause the production of methane which is even worse than co2 - Wood is way less dense than coal so even if the idea worked you would only be able to store a fraction of the amount of co2 - Its hard to imagine the sheer scale of collecting all the wood to ship back to the mines. As mentioned wood is much less dense than coal so the effort to ship the wood to coal mines would be much more difficult than shipping the coal out of the mines. Not to mention that the wood would be coming from a much wider area. There are ideas about burning wood to produce electricity, capturing the CO2 exhaust and pumping that deep underground. The concept is called Bio-Energy with Carbon Capture and Storage (BECCS).

olliej 7y ago

The carbon is essentially the entirety of the tree itself

deleted 7y ago

[deleted]

deleted 7y ago

[deleted]

Expez 7y ago

Yes, it's only captured until the tree dies. After that the tree rots etc and carbon is released again. The clue to net carbon capture is to plant new forests and make sure the forest stays alive. While the forest lives, all the CO2 is safely sequestered.

LeoPanthera 7y ago

It turns into wood! It's actually pretty amazing. I always though the physical substance of wood came out of the ground, through the roots, but in fact wood is made almost exclusively out of air. Trees are frozen air.

beat 7y ago
As an aside, that's also how we lose weight! When we burn away fat, we breathe it out.

evanb 7y ago

The carbon goes back into the atmosphere if you burn it. If you just let it decay, turn into top soil, and ultimately become entombed by the surface of the Earth it will, ultimately, suffer the fate of most of the ancient plants we today burn in their carbon-storage form: underground oil.

Spellman 7y ago

As it turns out, the vast majority of any plant is actually Carbon! That it got from the AIR!!!! I remember when my friends' brains were blown that all trees are essentially made out of "air" that got converted to wood. Technically it's the 2xCO_2 -> 2xO_2+2C and the Carbon that sticks around becomes the wood. (also insert Water and energy into that equation. Photosynthesis is crazy). And yes, if it gets burned or decomposed that carbon can get released back into the air (usually as CO2) but if you instead bury it you essentially lock it into solid form. And over years and years that becomes oil!

twic 7y ago
I'm really pleased to see people in this subthread being so excited about the fact that plants are made out of carbon they extract from the air. Question, though: isn't this something you learned in school?

Maximus9000 7y ago

As others have said the carbon is locked into the physical wood. When it rots or burns, that carbon is released back. However, you can hijack the process a little and keep the carbon locked away by doing things. You could use the wood as lumber or you could burn the wood in a special way which produces biochar.

dlazar 7y ago

Also not a chemist, but here's my basic understanding. The tree absorbs CO2 from the atmosphere and combines it with water (H2O) from the soil to produce more complex chemical compounds (such as carbohydrates). This process uses sunlight as the source of energy, and is better known as photosynthesis. The chemical compounds thus produced are used by the tree as structural material (the wood), or as stored energy (basically, reverting the photosynthesis reaction, aka "burning", releases the energy). If the tree matter gets consumed by animals, those animals are going to use the stored energy, and ultimately re-release the stored carbon as CO2. If the tree just dies and is allowed to decompose, bacteria and other microorganisms will do the same: they'll eat the carbohydrates that the tree produced, and they'll breathe out the resulting CO2. If the tree is burned as fuel, the CO2 gets re-emitted directly. So, to truly remove that CO2 from the atmosphere, the tree needs to be felled once it's stopped growing, and the resulting wood stored someplace where it can't be decomposed by microorganisms. Burying it is one solution to this (and this is what happened during the carboniferous era, when much of our coal and oil got created: dead trees fell in shallow swamps and were quickly buried under a layer of silt which prevented the decomposition). Again, I'm no expert, so I'm happy to stand corrected if I've made any mistakes above.

radicalbyte 7y ago
The easiest thing to do is to burn it into biochar and then either bury that or use it as a fertilizer on fields where it will get taken up in the soil. There are some active land management techniques which do something similar with shrubs/plants/grasses which generate an enormous amount of soil and therefore trap a lot of carbon.
- dlazar 7y ago
  Interesting, I hadn't realized pyrolysis (used to produce biochar) does not release CO2. Seeing "pyro" (Greek for "fire") I had assumed oxidation. Sounds like a good technique for making the wood "indigestible" for microorganisms. I wonder if it's worth doing energywise, compared with just burying it somewhere.

hn_throwaway_99 7y ago

Interesting tidbit about this. The reason we have so much fossil fuel in the first place is because of what happened during the Carboniferous era. Trees evolved the capability to produce lignin, the 'woody' material in trees. However, it took millions of more years for microorganisms to evolve the ability to decompose lignin. So instead of what happens today when a tree dies and rots, the tree died and just piled up in the forest. I always think it's amazing to imagine what a forest must have looked like during the Carboniferous with all these dead trees just piled high. Trees were essentially like today's plastic: non-biodegradable refuse that stuck around for millennia. Eventually all those trees got buried and turned into fossil fuels (mostly coal). And, interestingly, this process let to huge climate change back then, too - basically the reverse of what's happening now (and at a much slower pace). Trees sucked all this carbon out of the air and reduced global temperatures by about 8C. Edit: One other note - there were of course still forest fires during the Carboniferous. It's believed they would have been incredible raging infernos with so much undecomposed combustible material.

galangalalgol 7y ago
so when the ability to break down plastic becomes widespread amongs organisms and they devour all the microplastics in the ocean, our co2 levels are going to skyrocket...

thinkcontext 7y ago

Many have commented about carbon becoming part of the tree however one also has to consider carbon in the soil around the tree. Plants put carbon into the ground through their roots and leaves, bark and other material that comes off of them that then feeds soil bacteria, fungi, worms, etc. Think about the soil underfoot in a mature forest is versus that under a lawn. In the forest you have soft, airy soil that teems with life and goes down for meters, whereas a lawn is compacted dirt after about a foot. There's a huge difference in stored carbon between them. Its a complex ecosystem with the plants at the center, and trees, since they have the deepest roots do the best at promoting carbon uptake. Of course, if you clearcut a forest the soil ecosystem dies and the carbon eventually comes back out of the ground.