<p>The key word in your query is the word "essentially". Termites and bacteria die too. So whatever carbon was initially converted from the tree into termites or bacteria ends up mostly going to <span class="math-container">$\small\mathsf{CO_2}$</span> also. </p>

<p>Of course some carbon gets converted to carbonate and that can combine with calcium to form the mineral calcite. The tree can also get buried in mud and over eons get converted to coal or oil. </p>

CC BY-SA 3.0
2016-12-04T07:58:45.057Z
I suppose to the extent it biodegrades, the bateria etc mostly burn the organic material for energy rather than building cells, thus releasing most of the carbon to the atmosphere (and the rest soon follows as these creatures biodegrade).
Grumdrig
CC BY-SA 4.0
2016-11-12T22:07:33.227Z
2020-01-04T19:28:40.480Z
2020-01-04T19:28:40.480Z
MaxW
<p>When a forest is used for sustainable fuel, there is a range of age classes in the forest, some old, some middle aged and so on. Wood harvest takes the oldest trees leaving young trees to take their place. Young trees growing vigorously consume more CO<span class="math-container">$_2$</span> than the old ones. In such a forest, old trees not used for fuel will decompose over time producing some CO<span class="math-container">$_2$</span> and a smaller amount of methane. An even smaller amount of carbon will be left in the soil.</p>

CC BY-SA 4.0
2020-02-14T12:06:34.060Z
2020-02-14T12:20:56.313Z
2020-02-14T12:20:56.313Z
Thomas Young
<p>If organic matter is buried - such as in landfill - it will decay anaerobically, resulting in <span class="math-container">$\small\mathsf{CH_4}$</span> (methane) rather than <span class="math-container">$\small\mathsf{CO_2}$</span> (Carbon dioxide). Methane is about 30 times more harmful as a global warming gas. Hence the reason why it is important not to landfill organic matter such as paper, card or waste food. However landfill of plastics (which is generally derived from a fossil fuel) is carbon sequestration, resulting in a net reduction of global warming gasses. So waste must be sorted before incineration - incinerating plastics produces/releases much <span class="math-container">$\small\mathsf{CO_2}$</span> and drives global warming</p>

CC BY-SA 4.0
2019-08-31T07:37:49.360Z
2020-01-04T19:29:33.277Z
2020-01-04T19:29:33.277Z
Tomajar
<p>It's not so much the amount of <span class="math-container">$\small\mathsf{CO_2}$</span> released but the rate at which it would be released that contributes to the Greenhouse effect. Burning will release CO2 faster than any form of natural decomposition</p>

CC BY-SA 4.0
2018-10-11T13:58:18.357Z
What causes the greenhouse effect is the **accumulated** amount of CO2 in the atmosphere. The speed of additional amounts is not that relevant.
Jan Doggen
CC BY-SA 4.0
2018-10-12T11:05:34.637Z
Surely the quicker CO2 is released, the more it builds up, assuming the rate of CO2 absorption remains constant?
Grotbags
CC BY-SA 4.0
2018-10-11T12:16:55.693Z
2020-01-04T19:29:49.613Z
2020-01-04T19:29:49.613Z
Grotbags
<p>The idea that decomposers that consume the wood's carbon just die and release it is foolish. These decomposers are at the base of a complex food web that moves that carbon through a huge network. I haven't seen a study to quantify the amount of carbon released to the atmosphere, but it is an important question. I have seen many studies trying to get at the question of how much carbon is incorporated into the soil, but each situation is so different that it is hard to get a clear answer.</p>

CC BY-SA 4.0
2019-06-07T13:03:45.993Z
2019-06-07T13:17:58.833Z
2019-06-07T13:17:58.833Z
Jane Winn
<p>Burning wood for home heating could actually be a carbon credit.  Wood offsets combustion of oil, natural gas, propane, and the use of coal fired generation of electricity.  Wood left to rot, as the previous post note, is carbon neutral.</p>

CC BY-SA 4.0
2018-10-19T03:25:43.357Z
2018-10-19T03:25:43.357Z
Dick
<p>I can't quantify the answer, but intuitively, nearly all of a burning tree's carbon is converted to <span class="math-container">$\small\mathsf{CO_2}$</span> - assuming the fire is hot enough. You are correct in assuming that termites and bacteria convert some of the carbon to other organic species, as do fungi, yeasts, moulds, and slow weathering. In addition, some of the rotting tree's carbon is converted to soluble inorganic ions, humic, fulvic and tannic acids. So no, organic decay would not yield the same <span class="math-container">$\small\mathsf{CO_2}$</span> as burning.</p>

<p>This would make an interesting school or 1st-year uni science experiment. Burn some wood in a sealed environment, measure the <span class="math-container">$\small\mathsf{CO_2}$</span> evolved, then repeat the experiment with wood in a wet organic-rich isolated biome, and compare the results. I suspect it would make for an interesting paper with potential climate change policy implications.</p>

CC BY-SA 3.0
2016-11-12T22:09:11.737Z
You'd never get the wet wood to decay fast enough to measure the CO2.
MaxW
CC BY-SA 3.0
2016-11-13T04:30:57.740Z
OK, so it is an experiment that mighjt take a few years, but it is still do-able.
Gordon Stanger
CC BY-SA 3.0
2016-11-17T03:48:50.600Z
Forest fires usually leave stumps and roots unburned.
Keith McClary
CC BY-SA 4.0
2018-10-14T06:02:49.847Z
@GordonStanger it is possible to break down wood faster if you do use ants/termites for the first step,and it will act as an fertilizer for bacteria and  fungi.it will still take some time but not years(you mention this in your answer)and it is doable as a school project.
trond hansen
CC BY-SA 4.0
2022-10-29T16:43:43.690Z
What about all the carbon soot? It seems like burning converts more to solid carbon which isn't converted to CO2.
mchid
CC BY-SA 4.0
2016-11-12T09:39:56.493Z
2020-01-04T19:28:21.187Z
2020-01-04T19:28:21.187Z
Gordon Stanger
<p>Does a fallen tree left to decay release essentially all of its stored carbon as <span class="math-container">$\small\mathsf{CO_2}$</span> to the atmosphere? Or is the carbon uptaken by termites and bacteria, preventing its release to the atmosphere?</p>

CC BY-SA 3.0
2016-11-12T22:34:20.730Z
Some carbon ends up as methane in organic decay. Not in combustion. Not sure about the quantities.
Gimelist
CC BY-SA 3.0
2016-11-14T09:07:07.577Z
There might be a considerable difference in the isotope ratios. Bacteria tend to use light isotopes of each element first.
daniel.heydebreck
CC BY-SA 3.0
2016-11-17T03:47:09.867Z
[A few tons per hectare per year is sequestered in the soil.](http://www.ipcc.ch/ipccreports/sres/land_use/index.php?idp=28)
Keith McClary
CC BY-SA 3.0
2016-12-04T08:03:17.577Z
@Friddy I'm interested in this question in terms of greenhouse gas generation
Grumdrig
CC BY-SA 3.0
2016-12-20T18:55:46.657Z
Related question: http://earthscience.stackexchange.com/questions/7424/does-natural-plant-decomposition-release-more-greenhouse-gases-than-burning
Puffin
<carbon-cycle><co2><carbon>
Does organic decay release the same CO2 as burning?
Grumdrig
# Does organic decay release the same CO2 as burning?

(Asked by: username_0 on 2016-11-12)

Does a fallen tree left to decay release essentially all of its stored carbon as $\small\mathsf{CO\_2}$ to the atmosphere? Or is the carbon uptaken by termites and bacteria, preventing its release to the atmosphere?

**Tags:** carbon-cycle, co2, carbon

> **Comments:**
> **username_1**: Some carbon ends up as methane in organic decay. Not in combustion. Not sure about the quantities.  
> **username_2**: There might be a considerable difference in the isotope ratios. Bacteria tend to use light isotopes of each element first.  
> **username_3**: [A few tons per hectare per year is sequestered in the soil.](http://www.ipcc.ch/ipccreports/sres/land_use/index.php?idp=28)  
> **username_0**: @Friddy I'm interested in this question in terms of greenhouse gas generation  
> **username_4**: Related question: http://earthscience.stackexchange.com/questions/7424/does-natural-plant-decomposition-release-more-greenhouse-gases-than-burning  

---

## 7 answers

### Answer by username_12 on 2016-11-12. Score: 5 | Accepted answer

I can't quantify the answer, but intuitively, nearly all of a burning tree's carbon is converted to $\small\mathsf{CO\_2}$ - assuming the fire is hot enough. You are correct in assuming that termites and bacteria convert some of the carbon to other organic species, as do fungi, yeasts, moulds, and slow weathering. In addition, some of the rotting tree's carbon is converted to soluble inorganic ions, humic, fulvic and tannic acids. So no, organic decay would not yield the same $\small\mathsf{CO\_2}$ as burning.

This would make an interesting school or 1st-year uni science experiment. Burn some wood in a sealed environment, measure the $\small\mathsf{CO\_2}$ evolved, then repeat the experiment with wood in a wet organic-rich isolated biome, and compare the results. I suspect it would make for an interesting paper with potential climate change policy implications.

> **Comments:**
> **username_5**: You'd never get the wet wood to decay fast enough to measure the CO2.  
> **username_12**: OK, so it is an experiment that mighjt take a few years, but it is still do-able.  
> **username_3**: Forest fires usually leave stumps and roots unburned.  
> **username_13**: @username_12 it is possible to break down wood faster if you do use ants/termites for the first step,and it will act as an fertilizer for bacteria and  fungi.it will still take some time but not years(you mention this in your answer)and it is doable as a school project.  
> **username_14**: What about all the carbon soot? It seems like burning converts more to solid carbon which isn't converted to CO2.  

---

### Answer by username_5 on 2016-11-12. Score: 3

The key word in your query is the word "essentially". Termites and bacteria die too. So whatever carbon was initially converted from the tree into termites or bacteria ends up mostly going to $\small\mathsf{CO\_2}$ also.

Of course some carbon gets converted to carbonate and that can combine with calcium to form the mineral calcite. The tree can also get buried in mud and over eons get converted to coal or oil.

> **Comments:**
> **username_0**: I suppose to the extent it biodegrades, the bateria etc mostly burn the organic material for energy rather than building cells, thus releasing most of the carbon to the atmosphere (and the rest soon follows as these creatures biodegrade).  

---

### Answer by username_6 on 2020-02-14. Score: 3

When a forest is used for sustainable fuel, there is a range of age classes in the forest, some old, some middle aged and so on. Wood harvest takes the oldest trees leaving username_6 trees to take their place. username_6 trees growing vigorously consume more CO$\_2$ than the old ones. In such a forest, old trees not used for fuel will decompose over time producing some CO$\_2$ and a smaller amount of methane. An even smaller amount of carbon will be left in the soil.


---

### Answer by username_7 on 2019-08-31. Score: 2

If organic matter is buried - such as in landfill - it will decay anaerobically, resulting in $\small\mathsf{CH\_4}$ (methane) rather than $\small\mathsf{CO\_2}$ (Carbon dioxide). Methane is about 30 times more harmful as a global warming gas. Hence the reason why it is important not to landfill organic matter such as paper, card or waste food. However landfill of plastics (which is generally derived from a fossil fuel) is carbon sequestration, resulting in a net reduction of global warming gasses. So waste must be sorted before incineration - incinerating plastics produces/releases much $\small\mathsf{CO\_2}$ and drives global warming


---

### Answer by username_8 on 2018-10-11. Score: 1

It's not so much the amount of $\small\mathsf{CO\_2}$ released but the rate at which it would be released that contributes to the Greenhouse effect. Burning will release CO2 faster than any form of natural decomposition

> **Comments:**
> **username_9**: What causes the greenhouse effect is the **accumulated** amount of CO2 in the atmosphere. The speed of additional amounts is not that relevant.  
> **username_8**: Surely the quicker CO2 is released, the more it builds up, assuming the rate of CO2 absorption remains constant?  

---

### Answer by username_10 on 2019-06-07. Score: 1

The idea that decomposers that consume the wood's carbon just die and release it is foolish. These decomposers are at the base of a complex food web that moves that carbon through a huge network. I haven't seen a study to quantify the amount of carbon released to the atmosphere, but it is an important question. I have seen many studies trying to get at the question of how much carbon is incorporated into the soil, but each situation is so different that it is hard to get a clear answer.


---

### Answer by username_11 on 2018-10-19. Score: 0

Burning wood for home heating could actually be a carbon credit. Wood offsets combustion of oil, natural gas, propane, and the use of coal fired generation of electricity. Wood left to rot, as the previous post note, is carbon neutral.


---

