Soil Biological Fertility


Soils are alive! A variety of soil organisms live in the soil. These include bacteria, fungi, microarthropods, nematodes, earthworms and insects. These organisms live on soil organic matter or other soil organisms and perform a number of vital processes in soil. Other organisms are involved in transformation of inorganic molecules. Very few soil organisms are pests.

The role of soil organisms in soil fertility may involve the following:

  • helping soil to form from original parent rock material,
  • contributing to the aggregation of soil particles,
  • enhancing cycling of nutrients,
  • transforming nutrients from one form to another,
  • assisting plants to obtain nutrients from soil,
  • degrading toxic substances in soil,
  • causing disease in plants,
  • minimizing disease in plants,
  • assisting or hindering water penetration into soil.