None of the loops are open in the sense that it's all within the earth system as a whole. The issue is extracting carbon from geological deposits. Stuff about farming and methane is temporary and short term.

I don't mean to suggest we shouldn't compost or recycle things. Just that such measures are only indirectly related to carbon emissions.

We either stop extracting hydrocarbons from deep within the crust or else the problem will persist. (I guess technically we could industrially sequester the equivalent but that would almost certainly defeat the cost-benefit of extraction.)