Fertilizers provide vital nutrients that are the building blocks of all plant and animal life.
Agricultural produce removes nutrients from the soil and these must be replenished.
If nutrients are not replenished then soils become depleted and plant growth is restricted.
As agricultural production in Australia has increased over time, so has the demand for nutrients as illustrated in the following graph which also shows the effect of the prolonged dry period in the first decade of the 21st Century.
The graph plots the tonnes of three major nutrients, Nitrogen (N), Phosphorus (P) and Potassium (K) supplied as fertilizer in Australia from 1983 to 2013. In product terms, this has averaged just over 5 million tonnes per annum between 2002 and 2013.