Thanks for posting this John! When I first started presenting on biochar and why it's important in the soil people would claim I was overreaching with discussion of why the redox assistance of biochar for soil microbes was critical and that the soil microbes actually evolved to use biochar, which is why it works so well. Since there have been plants there have been fires (they make fuel and oxygen!) and so evolution has worked out how to take advantage of the fire situation. Early research on redox assistance to soil microbe metabolism was carried out in France and it's really nice seeing this understanding going "mainstream".
Since biochar lasts so long there have always been enough forest fires to build it up and keep it stocked up in the soil. Long term farming without fire will eventually run down the native biochar concentration and cause trouble (assuming other trouble doesn't stop long term farming in a place). It's great to see this knowledge base developing!!!
Great point, Greg. The Native Americans in my area burned the valley floor on purpose every year. Perhaps this result was one of their motivations, even if they might not have stated it exactly the same way.