Soil Classification equivalents

I am a geologist looking for information for a non profit organization (PANNA). They asked me to find map resources for the
world distribution of ""micro aerophyllic acid"" soils. Now, I have downloaded Keys Taxonomy and am slowly plowing through it.

My question is, what international soil types would fit this description? I believe that the micro-areophyllic acid description
might fit multiple types.

I have found several internet sources of soil maps, but have not been able to determine which soil groups to focus on.

Thanks for your assistance. My experience thrying to learn soil taxonomy has increased my respect for soil scientists.

Skip McIntosh
skip8mac@netscape.net