page60
60
2. Soil Fundamentals
Microbes cycle nutrients, including chemicals
in soil bedrock and plant tissues, which often
makes these nutrients available for use by
other organisms. Microbes may also be used
directly as food by other organisms. Indirectly,
many fungi and bacteria excrete enzymes
(similar to those in animal digestive systems)
into the soil. These enzymes break down
organic materials and the smaller compounds
that can be used by other organisms or plant
roots. Microbes’ growth and activity can also
break apart rocks, starting the process of soil
creation.
Because microbes are so much smaller
than plant roots, they can grow into soil
Under the
microscope:
Bacteria
Bacteria and Archaea
appear as symmetrical
specks, less than
5 micrometers, or
0.000195 inches, long
These were the first life
forms, and they are present
today in incredible diversity.
A spoonful of soil harbors billions
of bacterial cells, millions of fungal
cells, and other organisms such as
tardegrades and nematodes..
Microbes
What do microbes do?