[msandford]

> my problem is that it neither matches nor exceeds the carbon output of e.g. cattle.

I am having a hard time understanding this concern. If the cattle and grass combo are releasing more carbon than they're sequestering then shouldn't soil carbon be going down?

Conversely if carbon is building up in the soil despite cattle eating grass and presumably incorporating some of the carbon from what they eat into their bodies, where did that carbon coming from besides the atmosphere?

I really cant wrap my brain around the idea that carbon can be building up in the soil while simultaneously cattle grazing operations are a net carbon producer. What am I missing?

[TollingSteady]

Part of the problem when discussing greenhouse gas emissions is that we're not only talking about carbon dioxide, but also all carbon dioxide equivalents.

For example, one molecule of methane (CH4) contains the same amount of carbon [the element] as carbon dioxide (CO2), but is >= 28x more potent as a greenhouse gas than carbon dioxide (https://clear.ucdavis.edu/explainers/why-methane-cattle-warm...).

Therefore, when talking in carbon dioxide equivalents (i.e. making something carbon neutral), my understanding is that for 1kg of methane emitted by cattle, there would need to be ~28kg of carbon dioxide equivalent sequestered by the soil.

Even if cattle produced only CO2, to create a closed carbon cycle, it seems like soil would still be insufficient for carbon sequestering, unless you have massive tracts of land for relatively few cattle. Cattle need a constant input of feed, but it takes time to remove GHGs from the atmosphere.