Reply #16: Yes, I would be interested in links.

[GliderGuider]

Specifically, any having to do with soil remediation to restore carbon content and humus that has been damaged by normal agricultural practices. My understanding is that humus takes about 500 years to regenerate, but that may be in forests without any human intervention.

I also know about, and am a big fan of, terra preta. That could conceivably repair damaged soil over the course of two or three years, but it requires a lot of charcoal to do that - potentially 10 tonnes or more per hectare. That means the world could use over 50 gigatonnes of carbon as charcoal to replace lost fertility. To put it in perspective, that is 8% of all the carbon in all the vegetation on Earth, or about 8 years' worth of the carbon released by our fossil fuel combustion. The logistics make it look problematic when you consider doing it globally on 5 billion hectares.

What sorts of organic inputs are used to remediate soil in the transitions you know of?