Smelly soils
Hi michael - try this for size. Fungi smell mouldy (moldy) and acid
soils contain a high proportion of fungi. However, neutral soils have a
goodly proportion of streptomycetes and these (or some of them) can
produce geosmin, a volatile compound that SMELLS of soil - is indeed the
reason why fresh soil smells the way it does. A little party trick on
field courses is to get students to guess the pH of a soil from its
smell. Now - geosmin is not so difficult to pick up by GLC - how about a
project that ranks soils by pH and geosmin production ?
Peter Harris.
