ABSTRACT
A healthy agricultural soil is one capable of supporting the production of food and fibre to a sufficient level such that it meets the requirements of humans and animals (Doran and Parkin, 1994; Kibblewhite et al., 2008). The health of soil gives an idea of its overall fitness for carrying out ecosystem functions and for responding to environmental stresses as well as agricultural interventions such as irrigation, tillage and application of fertilisers (Lewandowski et al., 1999). Mineral fertilisers are applied to soil to supplement or substitute for biological functions considered inadequate or inefficient for achieving required levels of production. However, fertilisers may disturb the natural functioning of soil and may also affect the output of other ecosystem services. Mineral fertilisers play a critical role in the world’s food security, and the future challenge is to manage fertilisers and soil in such a way that food demands are continuously met and soil remains sufficiently healthy to support adequate food production with minimal environmental impact.
