[nostromo]

I’m confused…

If organic compounds break down in a landfill, they release greenhouse gasses. But the same happens when they break down as compost - something the website forgot to mention.

I support composting because I think it’s good for the planet to save space in landfills for things that need to be buried. But I don’t see how either approach actually helps climate change.

And, in fact, without much study, it seems like landfills are actually sequestering lots of carbon. So if our only focus is on climate change (and it shouldn’t be, to be clear) wouldn’t that be the winning option?

Regarding more potent greenhouse gasses from landfills - I believe most landfills in the US burn (or sell) their waste methane, which just turns it into plain ol’ carbon dioxide.

[danielheath]

Aerobic breakdown is totally different to anaerobic breakdown.

In composting you have to turn the compost periodically to keep it oxygenated, otherwise you get methane and poor compost.

[acomjean]

This.

Also "modern" landfills when filled tend to be "capped" (covered in plastic) so rain doesn't leach though into the groud water. If they have a bottom liner, these landfills are like the worlds largest plastic bags.

To prevent methane building inside the capped landfill, pipes are run and the gas is collected and sometimes "flared" [1]

Having dug into some old old landfills, it was like a time machine of 25+ year old stuff. nothing seems to rot well inside them (no water). papers readable. We found a glass bottle of what appeared to be grape soda.

[1]https://www.epa.gov/lmop/basic-information-about-landfill-ga...

[readams]

Plastic in landfill is sequestered carbon dioxide.

[chaostheory]

It’ll also help mitigate the loss of top soil for agriculture. It’s estimated that we’ve lost about 33% over the years in the US

[valbaca]

The idea is that compost is used as fertilizer. That fertilizer is used to grow plants, and plants reduce greenhouse gases.

[novok]

The CO2 that oil / coal / gas emit is "new" CO2 that the atmosphere never had, while most 'natural' CO2 & methane emissions gets recycled in a 10 year cycle, so it doesn't add to the net CO2 to the atmospheric systems.

On the other hand, agriculture emissions coming from animals and plant decomposition is small amount of agriculture's emissions in general anyway, so sequestering carbon is a bad reason to not compost, because of all the fertilizer benefits it creates, which means less need for artificialy created fertilizer. About %50 of fertilizer is the natural poop & compost kind.

[scientismer]

Oil, coal and gas are actually produced from biological sources, plants that lived millions of years ago.

It's even a bit ironic - there was a time when nature hadn't yet learnt how to break down trees, so a lot of trees accumulated (simplified, I think it is more a then new trick of plant cells that had no "natural enemies"). That organic material is what oil, coal and gas are made from. The irony is that from oil we now make plastic, and nature has not yet found a way to break down plastic. Since microbes can now digest trees, no new oil will be created. But maybe if large enough plastic deposits are accumulated, it could happen again?

(Details may be wrong, as I was too lazy to google, but the gist is, fossil fuels are actually made from organic sources).

[sentinel]

I believe the idea is that in a landfill those products will release CO2 and methane, whereas when composting they only release CO2. Methane is a more potent greenhouse gas, so that's another benefit to composting.

https://recycle.com/organics-compost-vs-landfill/#:~:text=La....

[yakubin]

Some gasses will be consumed by plants and fungi. Granted, methane won't be one of them. But CO2 will. Now, when compost is dumped on barren soil, there is nothing to consume the gasses.

[noxer]

A modern landfill where the gas is burned and used as energy source is way way better at reducing green house gases than fungi and microorganisms. The C02 wont go away but most of the rest way worse greenhouse gases.