I took some botany/plant physiology classes too many years ago, but I could probably answer the acid/base question. Are you still interested?

I'd love to talk about this further, but for now let me just say that hosting a strong compliment of microbes will "buffer" a lot of changes in the nutrient status, and pH of the soil.

Have you seen the Terra Preta thread:
http://www.scienceagogo.com/forum/ubbthreads.php?ubb=showflat&Number=8943#Post8943
on amendments to marginal soils?

~SA

Pyrolysis creates reduced carbon! ...Time for the next step in our evolutionary symbiosis with fire.