Indicate how protozoa may regulate not only the numbers of

. Indicate how protozoa may regulate not only the numbers of bacteria in soil but also the composition (i.e., the community make-up) of the bacterial flora.

soil science

Solution

Protozoa regulate bacteria populations by grazing on the bacteria. There by it stimulate growth of the bacterial population. Grazing can be thought of like pruning a tree – a small amount enhances growth, too much reduces growth or will modify the mix of species in the bacterial community. It play an important role in mineralizing nutrients, making them available for use by plants and other soil organisms. Bacteria eaten by protozoa contain too much nitrogen for the amount of carbon protozoa need. They release the excess nitrogen in the form of ammonium (NH4+). This usually occurs near the root system of a plant. Bacteria and other organisms rapidly take up most of the ammonium, but some is used by the plant. Thus, it plays major role in altering the community make up of the bacterial flora.