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Planting trees not always an effective way of binding carbon dioxide

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Re: Planting trees not always an effective way of binding carbon dioxide

#121

Post by pastacacioepepe »

wikfwikf wrote: post #61
colechristensen wrote: post #2

Yes you need to build ecosystems not just plant trees. Monoculture tree stands are often mostly empty of other life. You need to plant a variety of native species keeping track of keystone species and year round food production so that your forest supports other life.

Why do you care about the forest supporting other life? Isn't the goal just to take carbon out of the atmosphere?

> Isn't the goal just to take carbon out of the atmosphere?

I disagree. We also want to avoid ecological cascade effects in our ecosystems.

Re: Planting trees not always an effective way of binding carbon dioxide

#122

Post by westurner »

quixoticelixer- wrote: post #108
samatman wrote: post #18

Earlier quoted context omitted.

The efficient thing to do is render them into charcoal, yes. Biochar is a great soil amendment, and doesn't oxidize over decades or even centuries, depending. Putting it back in the mines is an option, if we ever need to stop rebuilding topsoil, which is itself getting urgent.

Biochar is also intensive and only converts a relatively small amount of that carbon into stable charcoal.

Hemp is compostable, though because it's so tough, shredding and waiting for it to compost trades (vertical) space & time for far less energy use than biocharification unless it's waste heat from a different process.

Bioenergy with carbon capture and storage (BECCS) > Biomass feedstocks doesn't have a pivot table of conversion efficiencies?: https://en.wikipedia.org/wiki/Bioenergy_with_carbon_capture_... :

> Biomass sources used in BECCS include agricultural residues & waste, forestry residue & waste, industrial & municipal wastes, and energy crops specifically grown for use as fuel. Current BECCS projects capture CO2 from ethanol bio-refinery plants and municipal solid waste (MSW) recycling center.

> A variety of challenges must be faced to ensure that biomass-based carbon capture is feasible and carbon neutral. Biomass stocks require availability of water and fertilizer inputs, which themselves exist at a nexus of environmental challenges in terms of resource disruption, conflict, and fertilizer runoff.

If you keep taking hemp off a field without leaving some down, you'll probably need fertilizer (see: KNF, JADAM,) and/or soil amendments to be able to rotate something else through; though it's true that hemp grows without fertilizer.

> A second major challenge is logistical: bulky biomass products require transportation to geographical features that enable sequestration. [27]

Or more local facilities

Re: Planting trees not always an effective way of binding carbon dioxide

#123

Post by po »

oliwary wrote: post #39

I recently looked up the difference in CO2 emissions between burning 1kg wood vs 1kg petrol. Surprisingly, the values are relatively close: Burning 1kg wood releases 1.65 - 1.8 kg of CO2. [0] Burning 1kg of crude oil releases 3.16 kg of CO2. [1][2] I would have expected the carbon density of oil to be much higher! To me, this suggests that a very naïve approach of growing trees and storing them in the places where we…

>I would have expected the carbon density of oil to be much higher!

You're comparing by weight, so density (which is mass/volume) isn't a part of it. 1kg of wood will take up more space than 1kg of oil. So the density is higher but equal weights of 'mostly hydro-carbon' will release equal amounts of CO2.

Re: Planting trees not always an effective way of binding carbon dioxide

#124

Post by dogcomplex »

orthecreedence wrote: post #85
vanderZwan wrote: post #46

Earlier quoted context omitted.

Do you know of any papers investigating how kelp or other seaweeds compare? I've heard some biologists informally claim that they would be even more effective because they can grow incredibly fast.

I thought trees were somewhat ideal because the carbon sequestered in them can be used as long-lived lumber. If the kelp sequesters carbon but then it gets released immediately when it decomposes or someone eats it, then it doesn't really solve the problem. We need to be putting carbon back into the ground where we got it, or at least converting into forms where it lives a long time on the surface (decades or centuri…

If you sink the kelp in the deep ocean apparently it likely takes quite a while for that carbon to make its way back through the ecosystem to the surface (decades, if not centuries). Don't have a source on that though.

Alternatively, convert kelp to biofuel and biodegradable plastic, reducing need for both CO2-intensive industries

Re: Planting trees not always an effective way of binding carbon dioxide

#127

Post by akira2501 »

Klapaucius wrote: post #16

Sequestring CO2 is a huge scale problem, and all solutions have significant flaws. Forests require vasts amounts of land, and storage is only assured as long as nobody decides to chop down the forest for other more pressing purposes (looking at you, Brazil). Storing CO2 in oceans (either in the form of "ocean fertilization" or by directly dissolving CO2 in seawater) could have huge and unknown consequences for marine…

> Forests require vasts amounts of land,

When people say this they typically mean the land is no longer usable for another purpose. I don't think this is the case with 'forests,' let alone adding more trees to empty spaces in currently populated areas.

> may be the only large-scale practical way going forward

Why must it be "large-scale?" "We could plant trees, in addition to implementing many other common sense measures and improvements collectively." "Yes, but is it web-scale?"

The only reason to do this is to create a large for profit industry driven solely by monopoly granting regulatory bodies as opposed to many individual markets driven by reasonable and non-discriminatory laws and enforcement.

Re: Planting trees not always an effective way of binding carbon dioxide

#128

Post by teaearlgraycold »

i5heu wrote: post #13
westurner wrote: post #4

"Hemp twice as effective at capturing carbon as trees, UK researcher says" (2021) https://hempindustrydaily.com/hemp-twice-as-effective-at-cap... : > “Industrial hemp absorbs between 8 to 15 tonnes of CO2 per hectare (3 to 6 tonnes per acre) of cultivation.” > Comparatively, forests capture 2 to 6 tonnes of carbon per hectare (0.8 to 2.4 tonnes per acre), depending on the region, number of years of growth, type of tr…

tonnes of carbon per hectare is not relevant. What you need is tonnes of carbon per hectare per year. We don't have enough space to let these plants be there, we need to convert them into coal and throw it back into the mines.

Ever wonder why ancient ruins are buried under feet of dirt? Plants will grow the ground towards the sky given enough time. We could perform a high carbon sequestration crop rotation to pile up dirt in place rapidly.

Re: Planting trees not always an effective way of binding carbon dioxide

#129

Post by oliwary »

po wrote: post #123
oliwary wrote: post #39

I recently looked up the difference in CO2 emissions between burning 1kg wood vs 1kg petrol. Surprisingly, the values are relatively close: Burning 1kg wood releases 1.65 - 1.8 kg of CO2. [0] Burning 1kg of crude oil releases 3.16 kg of CO2. [1][2] I would have expected the carbon density of oil to be much higher! To me, this suggests that a very naïve approach of growing trees and storing them in the places where we…

>I would have expected the carbon density of oil to be much higher! You're comparing by weight, so density (which is mass/volume) isn't a part of it. 1kg of wood will take up more space than 1kg of oil. So the density is higher but equal weights of 'mostly hydro-carbon' will release equal amounts of CO2.

That’s a very good point. It seems like the densities are relatively similar as well though [0][1]. Not saying they’re the same, but even the fact that they’re in the same order of magnitude was surprising to me. Seems like filling a 1km^3 with wood could offset all CO2 emitted for over 20 years!

[0] https://www.engineeringtoolbox.com/wood-density-d_40.html [1] https://www.transmountain.com/about-petroleum-liquids

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