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.


  • What are soil organisms, how do they help soil fertility?


  • Which elements are essential for plant health and which may be toxic to plants?


  • How do soil physical properties affect water movement and nutrient uptake through the plant roots?
  • Soils are Alive!

    • The complete soil health reference for farmers, consultants and researchers