1. N - Efficiency
Results
Katherine Cherry

2. Outline
Introduction
Efficiency
What?
Why?
Results
Future work

3. Introduction PhD student from the University of Nottingham.
Investigating ways to evaluate mitigation effectiveness.
Efficiency is one possible method.
Calculating efficiencies for WAgriCo farms

4. Data You have supplied us with lots of farm data! Farm Data N fixation
Livestock
Fertiliser
Bedding
Feed
Crop
Manure
Animal products
… And from this we can calculate nitrogen balances and efficiency ...

5. Efficiency – what is it?
N Efficiency is the proportion of imported N that is exported as ‘useful products’
Output
Input
X 100
Efficiency (%) =

6. Efficiency – How did we calculate it?
INPUTS
Imported manure
Fertiliser
Excreta
OUTPUTS
Exported manure
Exported livestock
Exported crops
Exported animal products
Calculated….
2005 – 2007 ‘Baseline’
2008 results
… and compared the two

7. Efficiency – what were we looking for?
Improvements in efficiency
…. Reduced inputs or increased outputs
… Less N available for loss

8. Results
Farms grouped by farm type
5.3
7.3
9.5
10.4
9.3
5.0
-0.43

9. Results
Farms grouped by LU/ha
5.5
8.8
9.3
5.33

10. Conclusions Arable farms more efficiency.
Largest improvements seen on arable and dairy, and beef and sheep.
Lower LU/ha farms more efficient.
Largest improvements seen in mid range of LU/ha.

11. Future work Which inputs / outputs changed?
Why did they change – result of mitigation measures?
How effective was mitigation?
How useful is efficiency?