‘Nutrient management’ is a very important concept in ensuring efficient nutrient use and avoiding or minimising adverse environmental impacts. It combines production and environmental aspects of nutrient input and output management, rather than considering manufactured fertiliser use in isolation. Complete nutrient management looks more widely at all sources of nutrient input and output and considers manufactured fertiliser use as part of the mix.
Nutrient input sources could include those:
- supplied through breakdown of organic matter (including applied compost or naturally occurring organic matter) and continued weathering of soil materials
- applied in fertiliser use
- deposited in urine and dung
- returned through the irrigation of dairy effluent
- added through the importing of supplementary feed
- nitrogen fixed from the atmosphere by clovers and other legumes
- deposited aerially
Nutrient outputs could include:
- nutrients taken off in products (e.g. fruit, vegetables, grain, logs, meat, wool, milk)
- crop residues removed from the paddock or burnt on site
- losses through erosion, leaching, surface flow and return to the atmosphere
- hay and silage sold off farm
- transfers to unproductive areas (e.g. raceways, stock camps)
Nutrients are essential for healthy plant and animal production, and deliberate nutrient inputs are often required to enhance productivity and address animal health issues. However, poor nutrient management can lead to consequences that are highly undesirable, environmentally, socially and economically. Implementing nutrient management planning will help land managers to maximise the efficiency of their use of nutrients, which will in turn avoid or minimise adverse environmental impacts and increase overall production efficiency.
This Code provides a procedure for the management of all nutrients used in primary production systems, with special emphasis on the management of manufactured fertiliser inputs.