Essential Nutrients | Toxicities and Deficiencies | Soil pH | Soil Sampling
Nitrogen is present in the earth's atmosphere, hydrosphere, biosphere and geosphere. Approximately 78 % of the earth's atmosphere is nitrogen, however, atmospheric nitrogen is unavailable for biological use. Atmospheric nitrogen must undergo an important process called fixation to make it available for plants to use.
Nitrogen transforms through several processes including fixation, mineralisation, nitrification and denitrification.
Nitrogen is critical to plant growth and reproduction, and the use of nitrogen fertilisers has dramatically altered the productive capacity of Australian soils. There are important environmental implications to be considered when using nitrogen fertilisers to ensure excess fertiliser does not run-off into nearby waterways threatening aquatic environments, or leach into groundwater causing the acidification of soils.
The following animation provides a simple illustration of the nitrogen cycle in an agricultural context.
Click on the animation of the nitrogen cycle to start.