Soil Biodiversity

Soil Biodiversity


Soil is one of the most fundamental and precious resources on the planet and the organisms which live in soil are essential to our well being. Although most of the organisms are invisible to the naked eye they all contribute to keeping our soil healthy and in sustaining our lives. The activity below the soil surface provides important ecosystem services - from the growth of plants, to the production of food and other crops and clean water and, production of fuels.


Different types of agricultural practices and systems affect the soil biota and the response may be either positive or negative depending on which part of the soil the biota e.g. fungal or bacterial is affected. For example, organisms which are sensitive to pH will be affected by the addition of lime; the bacterial: fungal ratio will be affected by the addition of mineral fertilizers and manures which alter the C:N ratio as will the effects of tillage. The consequences of the agricultural practice on the soil biota may be direct and far reaching. Organisms which are of benefit to agriculture and which may be affected include those responsible for:


1.      Organic matter decomposition and soil aggregation

2.      Breakdown of toxic compounds both metabolic by-products of organisms and agrochemicals

3.      Inorganic transformations that make available nitrates, sulphates, and phosphates as well as essential elements such as iron and manganese

4.      Biological nitrogen fixation into forms usable by higher plants


©FAO/Giuseppe Bizzarri
©FAO/Olivier Asselin