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There's a certain argument to be made for timber farming as a way to extend our temporary carbon sinks -- trees that fall over rot, releasing their carbon, tree

There's a certain argument to be made for timber farming as a way to extend our temporary carbon sinks -- trees that fall over rot, releasing their carbon, trees that are cut down and turned into houses may be protected from decay for tens or hundreds of years. You could really go whole-hog into attempting to maximize the amount of timber you can stuff into a house -- start building double-stud walls with 12 inch on-center spacing just to triple the number of 2x6's used, fall in love with giant cross-laminated timber panels, etc etc.

vkou 6y ago
That is incredibly labour and energy-inefficient. You're better off burying raw timber, as opposed to processing it, cutting it up, transporting it to a worksite, and paying professionals to hammer it into place.
- saalweachter 6y ago
  How do you feel about baking the timber in solar ovens first, before burying the charcoal, to go full terra preta?
elihu 6y ago
It seems to me that the low-hanging fruit is to sequester the sawdust and scraps that result from sawing logs into boards. I assume that much of that ordinarily finds its way into other products (paper, particle board, etc...), but that it's economically less valuable than usable boards and thus burying it the ground has lower cost. There does seem to be increasing interest though in making large structures out of wood, so maybe that's a pretty good route for carbon storage.
henearkr 6y ago
Just to precise, "tree-roting" is incredibly slow, and the tree mainly turns into other living forms (thus, also sequestered carbon) rather than in carbon dioxide (one part does, but far from 100%). It's like when you eat, you do not turn your food in pure gas, do you? And then the excreted/remaining mass will be buried etc (and will partly be turned into earthworms, nematodes, bacteria, moss, fungi, etc).
- saalweachter 6y ago
  Hmmm, that's an interesting question. A person breaths out about 2.3 lbs of CO2 each day, which amounts to 0.6 lbs of carbon, all of which must have come from your food. Meanwhile, a person defecates about 1 lb per day, about 75% of which is water. Of the residue, about 25-50% of it is bacteria, and the remainder the undigested portion of your food. Bacteria is typically accounted 53% carbon; the undigested fats, carbohydrates and proteins will vary a lot in percentage, but is 40% carbon for carbohydrates, 50% for proteins, and "more" for fats. Which leaves a lot of variance, but something like 0.15 lbs of carbon exiting at as a solid seems like a reasonable estimate. So the answer would be: you turn about 80% of the carbon in your food into CO2 gas.
  - deleted 6y ago
    [deleted]
  - henearkr 6y ago
    That seems a lot, 80%. But after reading several times your calculation, it seems legit. Thanks. Then, as a conclusion, when you eat you delay 20% of your carbon footprint, and a fraction of these 20% may well be stored for a long duration (in sediments, or back into the food chain, etc). Then again, similarly, the fallen leaves of trees may store a fraction of their carbon for a long duration.
    - saalweachter 6y ago
      You can basically look at that 80% as the efficiency of the body machine. To a first approximation, once we have all the matter needed to build a body, you are just taking in carbon to oxidize it for fuel.
  - henearkr 6y ago
    https://phys.org/news/2021-04-trees-world-offset-society-carbon.html https://phys.org/news/2021-04-trees-world-offset-society-car... Here: > While this process naturally releases CO2 through the respiration (or breathing) of microbes that break down dead organisms, some fraction of plant carbon can remain underground for decades or even centuries. Together, land plants and soils hold about 2,500 gigatonnes of carbon—about three times more than is held in the atmosphere. This was the point I wanted to make, probably worded awkwardly.

vkou 6y ago

That is incredibly labour and energy-inefficient. You're better off burying raw timber, as opposed to processing it, cutting it up, transporting it to a worksite, and paying professionals to hammer it into place.

saalweachter 6y ago
How do you feel about baking the timber in solar ovens first, before burying the charcoal, to go full terra preta?

elihu 6y ago

It seems to me that the low-hanging fruit is to sequester the sawdust and scraps that result from sawing logs into boards. I assume that much of that ordinarily finds its way into other products (paper, particle board, etc...), but that it's economically less valuable than usable boards and thus burying it the ground has lower cost. There does seem to be increasing interest though in making large structures out of wood, so maybe that's a pretty good route for carbon storage.

henearkr 6y ago

Just to precise, "tree-roting" is incredibly slow, and the tree mainly turns into other living forms (thus, also sequestered carbon) rather than in carbon dioxide (one part does, but far from 100%). It's like when you eat, you do not turn your food in pure gas, do you? And then the excreted/remaining mass will be buried etc (and will partly be turned into earthworms, nematodes, bacteria, moss, fungi, etc).

saalweachter 6y ago
Hmmm, that's an interesting question. A person breaths out about 2.3 lbs of CO2 each day, which amounts to 0.6 lbs of carbon, all of which must have come from your food. Meanwhile, a person defecates about 1 lb per day, about 75% of which is water. Of the residue, about 25-50% of it is bacteria, and the remainder the undigested portion of your food. Bacteria is typically accounted 53% carbon; the undigested fats, carbohydrates and proteins will vary a lot in percentage, but is 40% carbon for carbohydrates, 50% for proteins, and "more" for fats. Which leaves a lot of variance, but something like 0.15 lbs of carbon exiting at as a solid seems like a reasonable estimate. So the answer would be: you turn about 80% of the carbon in your food into CO2 gas.
- deleted 6y ago
  [deleted]
- henearkr 6y ago
  That seems a lot, 80%. But after reading several times your calculation, it seems legit. Thanks. Then, as a conclusion, when you eat you delay 20% of your carbon footprint, and a fraction of these 20% may well be stored for a long duration (in sediments, or back into the food chain, etc). Then again, similarly, the fallen leaves of trees may store a fraction of their carbon for a long duration.
  - saalweachter 6y ago
    You can basically look at that 80% as the efficiency of the body machine. To a first approximation, once we have all the matter needed to build a body, you are just taking in carbon to oxidize it for fuel.
- henearkr 6y ago
  https://phys.org/news/2021-04-trees-world-offset-society-carbon.html https://phys.org/news/2021-04-trees-world-offset-society-car... Here: > While this process naturally releases CO2 through the respiration (or breathing) of microbes that break down dead organisms, some fraction of plant carbon can remain underground for decades or even centuries. Together, land plants and soils hold about 2,500 gigatonnes of carbon—about three times more than is held in the atmosphere. This was the point I wanted to make, probably worded awkwardly.