Nutrient Balances for Australian Natural Resource Management Zones

Estimating nutrient inputs and removals in Australian agricultural regions.


25 Mar 2014

2013 Annual Interpretive Summary

This project has collated additional fertilizer use data using information from the Australian Bureau of Statistics farm practices surveys. This collects small area (down to local government areas) data by industry and nutrient, and is reported every four years. The objective of this analysis is to estimate nutrient use by industry and region - as such data is not currently widely available. The first analysis indicates that small area data grossly overestimates the amount of nutrient used from industry figures. This conclusion was reached by aggregating regional industry data on fertilizer use to state level industry estimates of fertilizer use.

Some data validation undertaken using dairy industry survey data indicated that the average N use on grazed dairy pastures was 71 kg N/ha, and this is most commonly applied in two or more applications. The use of K declined over the past decade, but has now recovered to levels recorded in the 2000 survey. Superphosphate is still the main P source, although diammonium phosphate (DAP) is commonly used. National nutrient use data were estimated using production data sourced from the Australian Bureau of Agricultural and Resource Economics and fertilizer data from Fertilizers Australia, along with estimates of fertilizer use by crop made by the International Fertilizer Industry Association. During the period of 2006-2007, wheat partial factor productivity (PFP) was 41 kg grain/kg N and 87 kg grain/kg P. In 2010-2011, PFP was 60 kg grain/kg N and 159 kg grain/kg P. Similarly, partial nutrient balances (PNB) for wheat were 0.86 for N and 0.36 for P in 2006-2007, and 1.27 for N and 0.67 for P in 2010-2011. These values indicate the temporal variability of these measures of nutrient use efficiency and that long terms trends are likely to be a more reliable indicator than values from one or two years.