Amazonian Dark Earths: Explorations in Space and Time
Dr. Bruno Glaser & Prof. William I. Woods (Eds.)
Springer, 2004

Now on Kindle!
I'm sure happy (w/ lots to read).

Erich, This is the book!
Section 8 is by the author you mention....

Sequential P Fractionation on Relict Anthropogenic Dark Earth of Amazonia:
Johannes Lehmann, et al.
smile

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