As discussed earlier (Figure 1), soils
can be characterized according to their in-
digenous microflora which perform putre-
factive, fermentative, synthetic and zymo-
genic reactions and processes. In most
soils, these functions are going on simul-
taneously with the rate and extent of each
determined by the types and numbers of
associated microorganisms that are ac-
tively involved at anyone time. A simple
diagram showing a classification of soils
based on the activities and functions of
their predominant microorganisms is pre-
sented in Figure 2 (p. 16).