Mineralisation Change of an element from in an organic form to an inorganic form by microorganisms
Denitrification The biological reduction of nitrate to ammonia, molecular nitrogen or the oxides of nitrogen, resulting in the loss of nitrogen into the atmosphere
Nitrification The oxidation of ammonia to nitrite and nitrite to nitrate by microorganisms
N-immobilisation Is the opposite to mineralisation, being the conversion of soil mineral nitrogen into organic forms
Fixation The transformation of elemental nitrogen in to an organic form by microorganisms
Humification The decomposition of organic matter leading to the formation of humus