I suggest that you read a basic book on soil microbiology, such as
"Introduction to Soil Microbiology" by Martin Alexander. It has a chapter
on the carbon cycle and a chapter on the nitrogen cycle, as well as an
overview of the soil environment. It is basic enough to understand with
little or no biology background. Good Luck.
Jeannie Leggett
246 Agricultural Engineering Building
The Pennsylvania State University
University Park, PA 16802
(814) 863-7710
FAX (814)863-1031