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by carpdiem 1966 days ago
Forests are not perpetual carbon sinks, as trees eventually die and then decompose, releasing their carbon back into the atmosphere.

At best, a young and growing forest can be a temporary carbon sink, until it reaches maturity (and steady state).

Alternatively, a forest might support continual carbon sinking if and only if the recently dead and/or mature trees were somehow harvested and treated/stored in such a way that their carbon would not decompose and re-enter the rest of the biosphere.

3 comments

Is that accurate? I can't believe that decomposition releases _all_ of the carbon into the atmosphere. Certainly a good amount of it is sequestered into the ground (e.g. coal). Thus a standing forest is never completely carbon neutral.
You are a bit out of date on this, wood isn't really turning into coal anymore these days, since bacteria and fungi have developed the ability to decompose lignin 300Ma ago.

The only thing comparable these days is peat bogs that act as carbon sinks (because their plant matter does not decompose due to acidic and anaerobic environment).

Peat bogs are flammable and can often catch fire, which in turn releases CO2. On timescales that matter, they are but temporary measures.
How exactly would wood just turn into coal, once it dies and falls down? You need really high pressures to form coal, this just doesn't happen without the residual biomass getting burried in some massive geological event. Dead trees are eaten by mushrooms and insects, which all produce CO2.
Broadly speKing, it is - coal does not really form on the timelines relevant to human civilisation
Yes. We should build more using Wood and less using Concrete.
We could make oil or coal and put it under the ground.