[alecmg]

I would love to have more trees.

But not for reason of sucking CO2. Please understand that forests are CO2 neutral. Any CO2 a tree consumes in its lifetime will be converted to leaves and wood and eventually fall to the ground and be converted by insects, fungi and bacteria BACK to CO2.

To get rid of CO2 from atmosphere we almost need to do the opposite, chop down trees and bury trunks somewhere where the don't decompose.

[cygx]

Existing forests are neutral. Growing new ones is not.

[GlenTheMachine]

Exactly. I get very frustrated by these conversations..

Wood sequesters CO2. Growing more wood will, trivially, sequester more CO2. Is that sequester "as good" as sequestering it deep underground? That depends. If it is sequestered by an ecosystem that persists over time - in other words, if it is sequestered in a forest, and that forest remains there even if the individual trees die and decay - then yes. The CO2 that is pulled out of the atmosphere stays out of the atmosphere unless the forest disappears.

[Gupie]

There is a case for burying charcoal,

https://www.technologyreview.com/s/407754/the-case-for-buryi...

[alecmg]

Use more energy to heat up biomass and convert it to a useful energy rich state and then ... bury it.

If this is the best solution to CO2 problem, I would rather have a CO2 problem.

[ryanmercer]

So, there are actually companies looking at generating renewable energy WHILE making biochar, one of them that comes to mind is in Australia - although their website seems to be gone here is an article that still exists https://biochar-international.org/pacificpyrolysis/

Basically they were (are?) for 12~ years were powering up to a [200kw generator proccessing up to 300kg](from my previous notes about them) of material an hour of dry biomass. Stuff like collected lawn clipping and branches. You could also use waste like paper sludge, sugar cane refuse, waste water sludge (feces and toilet paper), wood waste from milling, used grain from breweries and distilleries, organic waste from industrial sources etc.

Go watch videos on making char cloth, it's a similar process. With char cloth you basically take a can that's mostly air tight, poke a hole in the top, place natural fibers inside like some scrap denim, replace the lid and heat the contents. The gas that gets cooked off is actually flammable and can be a fuel.

The process they were using required a rather large machine and ended up not only producing biochar but output more energy than went into the system by being much more controlled and capturing the gasses.

I suspect you could also manufacture a system that instead just uses concentrated solar power to process material, instead of needing to get up to 1000C though you'd only need to get around 450C (based on past studies for optimal temperature for producing biochar with optimal soil drainage properties), you could pull the gas off of that and pipe it some distance away to another facility doing the same a more traditional way, using the gas as the fuel source for it.

[mft_]

Wouldn't the solution be planting enough new trees to replace the newly-dead ones? i.e. keeping a sufficient mass of trees growing, always? That way, you'd have a continual carbon sink?

[alecmg]

It is only a sink if you take carbon out of it. Else it is a closed system. For every tree growing, there is somewhere a tree rotting.

[deaps]

I remember when the whole 'CO2 neutral' thing came into my mind, not long ago when I read the article about the 53 year old sealed garden [1].

Definitely interesting, but I think that a fast-growing tree would probably create more O2 (consume more CO2) in its first 10 or so years. I think that big, old forests where large pieces of wood are dropping and rotting, etc, may tend to be on the neutral side of things.

I think that some studying of what type of trees to plant, etc is definitely in order. Certainly some drop less - and quite possibly they determine that the trees need cut down, turned to paper or paper products, and replanted every number of years.

When I think of the situation you are describing (CO2 neutral), I picture a dense, damp forest area. I feel like trees, properly spaced, may lean more toward co2 consumption.

Anyway, just a thought...

[1] https://biologicperformance.com/sealed-bottle-terrarium-gard...

[peteradio]

Is rate out same as rate coming in? I really don't think that is the case, what would the natural cause be to make an exact match between rot and growth? Duff accumulates, forest floors rise.

[bamboozled]

What do you think the heavy dense part of the tree is made from ? Yes largely carbon.

[maxmcorp]

I looked it up. It takes about 15 trees to absorb 1 tonne of CO2. Which is used for a 10.000 km flight.

[wolco]

For every 1,000 you fly plant 1.5 trees

[notabee]

Flights will consume those miles and fuel much faster than those trees can grow to consume the CO2 from them, so you'd need an exponential number of additional trees planted in anticipation to offset future flights up to a certain point where you run out of reasonable land to grow trees on, or water and nutrients, and then you'd have to expend energy to chop the whole forest down and bury it to still come out ahead. The only way out of the debt spiral is to stop consuming fossil fuels for flight.

[ptah]

buried trunks decompose though

[alecmg]

without oxygen access decomposiotion wouldn't result in CO2. Bottom of a swamp essentially, a peat bog.