1. An industry approach and recommendations… Nutrient performance indicators and nutrient use efficiency Rob Norton & Tom Bruulsema, IPNI ANZ/NEA on behalf of IPNI

2. The role of IPNI………. to develop and promote scientific information about the responsible management of plant nutrition for the benefit of the human family Our stakeholders- Member companies, scientists, advisors and farmers. This approach - The perspective presented here is to consider how nutrient performance indicators – such as removal/use ratio (Partial Nutrient Balance) can be use to promote responsible management of plant nutrients (in this case N) AND enhance food security and soil health.

3. Why indicators? – The importance of farmers Measure and improve systems – indicators of management – improved by farmers through policy – statements of accountability – regional/national government Grain production water use efficiency – Water limits yield – Management targets WL Yield – Benchmark 20 kg/ha/mm seasonal rain – Every farmer & advisor has this target. Frechn & Schultz, 1984

4. Why indicators? – The importance of farmers Measure and improve systems – indicators of management – improved by farmers through policy – statements of accountability – regional/national government Nutrient Performance versus Nutrient Efficiency – We all to be more efficient – but how – Efficiency is one aspect of nutrient performance – Performance is a more appropriate term – Efficiency is not always fundamental to system improvement. – Effectiveness is what farmers consider - not efficiency.

5. IFA Nutrient Stewardship Working Group TFI Sustainability Task Force CFI Nutrients Committee EU Nitrogen Expert Panel International Nitrogen Initiative

6. Key considerations for Nutrient Use Efficiency (NUE) as a performance metric Many ways - Partial Nutrient Balance (output/input ratio) Optimum - neither too high nor too low One of a complement (NUE + Yield + Soil Fertility) Data - availability and timeliness of reporting Trend - past, present, future Nutrient - N, P, others Targets - set regionally, not globally Interpretation in site-specific context Engage with farmers to develop aggregated values Incorporate uncertainty into the measures IFA, June 2014 IPNI, August, 2014

7. Complementary sets of nutrient performance indicators Enablers (process metrics) Actions (adoption metrics) Outcomes (impact metrics) Extension & professionals Infrastructure Research & innovation Stakeholder engagement [Require regional definition of 4R] Cropland area under 4R (at various levels) Participation in programs Equity of adoption (gender, scale, etc.) Food & nutrition security Productivity Nutrient use efficiency Land quality, soil health Air & water quality Economic value Land conservation, natural habitat DRAFT

8. Will any one indicator be useful The purpose of using nutrients is to grow food, feed, fiber and fuel. Need to link nutrient performance to – Productivity (eg yield gaps) – Potential losses to the environment – Change in soil nutrient status One number cannot convey that complexity.

9. Form of expression – NUE can be defined and calculated in many ways NUE termCalculated from Typical levels for N (maize or wheat) PFPY/F40-80 AE(Y-Y 0 )/F10-30 PNBR/F >100% = deficiency <100% = surplus RE(U-U 0 )/F 50% (whole-plant) 33% (grain only) Y=yield, F=fertilizer, R=removal, U=uptake … but always, a ratio of output/input Dobermann, 2007

10. What information do these terms convey? PFP – How productive is this crop (cropping system) in comparison to its nutrient (fertilizer) input. – By definition this declines with increasing nutrient input PNB – How much of the nutrient is removed in product relative to the amount of nutrient (fertilizer) applied. – defines one of several transfer processes. – It is not necessarily an environmental indicator. – Can also be indexed by area/product eg /ha or /t grain Intensity measurement

11. Based on data from Cassman et al., 2002 Assessing impact on short term crop uptake and long-term soil nutrient supply is critical in evaluation of system efficiency

12. Midwest Corn - NUE improvement 12% increase in N fertilizer use 51% increase in N efficiency Since 1975: Data sources: USDA Ag Chem Use Survey & Annual Crop Production. 1975 40 kg grain/kg N 2008 70 kg grain/kg N

13. Efficiency & Effectiveness for farmers PFP & PNB decline with increasing inputs Economic response - marginal cost versus marginal return – Cost of input compared to value of output – Near Ymax Yield Gap

14. Metrics for productivity, yield gap, and yield gap arising from crop nutrition are difficult to measure Pasuquin, JM et al. 2014 Field Crops Research 156:219–230 Maize in Southeast Asia Yield Gap, Attainable – Farmer Practice, t/ha 0.70.91.1

15. N in grain systems – indicators of value Canola/Wheat/Barley/Pulse (70 kg Ndfa/ha) Time 1996-2013 N balances/productivity @9 kg P/ha t/haPFPPNB*$/haOC% Annual N rate (kg N/ha) 0 1.95 -- 258 1.18 a 20 2.30 1092.94 275 1.24 a 40 2.31 581.60 291 1.27 a 80 2.31 280.92 298 1.25 a 160 2.46 140.47 202 1.26 a * N only from fertilizer

16. Removal to Use Ratio (PNB) Widely referenced (IFA, SDSN, INI, etc) Scalable from field to farm to region to nation. It is a ratio, does not have yield nor scale of balance (ie impact) Quality of and confidence in input data PNB = Nutrient Removal / Fertilizer Nutrient Supplied NR = Nutrient concentration * Product Removal NS = Fertilizer applied

17. Nutrient concentrations – Wheat grain N concentration - Location/T ype MC % N (kg/t FW) nRef Springns21.0ns IPNI Winterns19.0ns IPNI Hard Winterns20.5ns NRCS Soft Winterns17.0ns NRCS Aus1121.0ns IPNI Qld 1991- 1999 1121.113 QDN R Vic 1995- 1998 1117.4106 Pivot Grain Barraclough, P.B.et al. 2010. Eur J Agron 33, 1-11.

18. Values for Grain Nutrient Concentrations Survey of Australian Canola grain from national variety trials, 2013. Mean 4.28% ±0.62. CV 14% Significant regional differences – eg within South Australia – 3.69 to 4.96 Immediate uncertainty in the PNB derived from these figures.

19. Disaggregated fertilizer use by crop data IFA publications – 2 publications only, 2006 23; 2010 - 27 FAOstat – total include pastures – Lasseletta attempted to disaggregate using a pasture & N use trendline US – good quality data at regional level from industry but not by crop. IPNI – NuGIS, AgStats, Australia, Brazil & India Australia – farm survey data of fertilizer use by farm type, and regional industry values.

20. Australia – N Use and PNB by Industry Type Nin 2007/8 (kt) N PNBArea (Mha) Horticulture Vegetables 12.6 0.610.8 Grapes 6.0 0.610.9 Pome Fruit 0.7 0.470.1 Stone Fruit 0.5 0.570.1 Citrus Fruit 1.6 0.370.1 Livestock Sheep 22.6 1.5041.3 Beef 31.5 3.12260.6 Dairy 62.1 0.852.6 Sheep/Beef 7.7 2.6129.7 Mixed 107* 1.6521.8 Grains Rice 1.1 0.980.2 Grains 335 1.6327.7 Cotton 24.2 0.530.8 Sugar 24.7 0.950.7 Total Sum 637.3 1.52387.4 Farm Survey Uncertainty 850 kt N sold (FA) “Crops” 78% N use Vegies – Manures Mean N = 15 kg/ha PNB 1.58 * N mainly used on cropping activities

21. Scale of fertilizer use data – eg Muller et al. Nature 490, 254.k 50 kg N/ha

22. Current estimates using public data. FAOStat – crop production data 2006, 2010. From their on-line database. What constitutes a CROP – Sugar? Oilpalm? Fertilizer use by crop – derived from IFA publications covering 2006/7 and 2010 FAO stat not disaggregated. Crop nutrient concentrations from IPNI crop

23. All cereals: N partial nutrient balances

24. Annual oilseeds – N partial nutrient balances

25. By ranking – lower quartile, upper quartile

26. PNB among crops CropProduction (Mt) Area (Mha) PNB kgNr/kg Na Wheat6022110.76 Rice6391550.56 Corn7071470.55 Other Cereals2861651.23 Oilseed (annual)98680.73 Soybean2439914* Oilpalm (FFB)210140.81** Sugarcane (cane)2700380.89 ** What value is it to know the differences among crops for PNB? Excluding BNF ** Excluding recycled nutrients from processing

27. How to consider fixed N - ~100 Mha of soybeans – 950 kt of N applied – 1/3 rd of that on 8 Mha in China – 55 kg N/t – so 240 Mt removes 13,000 kt N Do we assume soybean to be N neutral? – Salvagotti et al, 2008 FCR ON AVERAGE 50-60% of soybean N demand is met by BNF 80% PNB suggested – Peoples et al. 2009 Symbiosis Suggests 68% of soybean N demand is met by BNF Gross Ndfa of around20 Mt in food legumes. – Explicit assumptions in dealing with these. Legume based pastures/alfalfa in rotations -

28. The particular role of pastures Not uncommon to have cropping systems incorporating short or long term legume pasture phases Significant contribution to N economy – example Australia (Angus 2001 AJEA) – Fixed N by pastures – 1,320 kt – Fixed N by crops – 235 kt – Atmospheric deposition - 160 kt – Fertilizers – 750 kt Should annual sown pastures be included as crops?

29. Allocation to BNF eg Lassaletta et al. 2014 Environ. Res. Lett, 9, 105011 70% 30% Not a criticism of this paper, it is comment on the adequacy of data to undertake regional assessments. The assumptions were clearly stated and reasonable on the basis of the information used.

30. Understanding other inputs/outputs Use of “Mill Mud” in sugar cane – PNB 0.93 – Recycle 150 t/ha onto fields – 120 kg N – Cartage costs means uneven return. Burning or removing crop residues – Wheat straw = 0.5 kg N/t NHI ~0.8-0.9 (linear?) Burned = 70% lost Carted for biofuel or similar – 100% loss Use of manures and composts as nutrient sources.

31. Nutrients on Dairy Farms – example for N kg/ha Gourley et al. 2012. APS Silage 7.5 (0-103) Hay 11.2 (0-223) Conc 52.5 (0-222) Fert 104 (0-424) Animal 4.6 (0-62) Irrig/Air 0.1 (0.1-15.9) N fixation 16.6 (0-289) Milk 58.3 (17-190) Animal 11.8 (0.2-78.1) Forages 0 (0-11) Manure 0.0 (0-0) NUE +192.8 kg/ha 17.0 g/L 70/196 35% 70/104 65% Numbers in kg/ha

32. Nutrient Performance Indicators Need to be: – Systematic in their estimation – Scalable national, regional relevant to farm and field scales also – Transparent and referenced – Assumptions explicit (fertilizer, fixed, manures). – Include an assessment of confidence. – Capable of repeated measures – frequency?

33. IPNI Metrics North America: NuGIS & Soil Test Summary

34. Figure 4.1: Inputs of N to US agricultural land, including recoverable manure, legume fixation, and commercial fertilizers, as compared to removal by crops (adapted from IPNI NuGIS, 2011). [In Robertson et al., 2012, Biogeochemistry]

35. NuGIS USA 2012, partial P balance, removal/use NUE varies spatially

36. NuGIS, 2014 NUE varies temporally – prices and weather

37. Frequency distribution of soil test P

38. Relationship of  STP with PNB, 12 corn belt states

39. P N Australia Nutrient Balances

40. N - PFP Fixen et al. 2014 PFP @ particular yields

41. N - PNB Fixen et al. 2014

42. NUE trajectories over 48 years ↑ yield stable PNB Lassaletta et al., 2014, Environ. Res. Lett. 9 (2014) 105011 (9pp) PNB 100% PNB 47% Going beyond a number

43. Contrasting trajectories Lassaletta et al., 2014, Environ. Res. Lett. 9 (2014) 105011 (9pp) Yield high Increase slowing Lowering of NUE Yield increasing Increase high Increase of NUE Yield low Increase coming High NUE

44. Challenge - Translate into farmer practice, ie $ and yields Australian growers know about WUE 20 kg/ha/mm What is the nitrogen use efficiency? – Partial Factor Productivity – Partial Nutrient Balance 4R practices linked to these indicators. RegionCereal PFP kg gr/kg N Cereal PNB kg N / kg N Australia520.82 North America 450.68 SS Africa1231.89 East Asia320.46 World440.66

45. Mean is interesting but not informative Accounting for nutrients – – Whole farm balance – 192 kg N/ha (47-601) – Productivity balance – 17 kg N/L (9-45) – Removal to Input – 25% (14-50) – Fertilizer N 53% of N inputs 102 dairy farms in NY – Cela et al. Cornell – 5 year study – buy-in – target of N balance at which 75% of farms 102 kg N/ha – 4R nutrient management – Feed management

46. Importance of Farm Scale Assessments Fertilizer is used within a farming system – Farms are more important than crops or fields or regions – Nutrient management in done across crops in rotations Fertilizer use is an agronomic & economic decision – Decision is based on a response curve & the yield gap – But removal to use ratios are largely irrelevant to farmers Better nutrient performance will rely on engagement with farmers – Where the rubber hits the road.

47. Disaggregating data and indicators Compromise between scale and precision – can have an approximate answer at a very broad scale (policy) – can have a precise answer at a narrow scale (management) Farmers are when interventions to alter removal to use metrics occur – Right Source – enhanced efficiency sources – Right Rate – to match the economic optimum? – Right Time – to match plant demand – Right Place – where losses are least

48. Summary: Farm scaled, linked to soil, productivity, environment & adoption Global sustainability initiatives demand metrics. Nutrient performance is more than NUE; it includes productivity and soil health; requires complementary metrics. Forms of nutrient use efficiency vary – clarify units. Source, time and place, as well as rate, impact nutrient performance. Aggregating farm scale data will help farmers balance yield, efficiency and soil health. “Nutrient use efficiency is a useful, complex, and incomplete indicator of crop nutrition performance”

49. Challenge: availability & reporting of data

50. Formed in 2007 from the Potash & Phosphate Institute, the International Plant Nutrition Institute is supported by leading fertilizer manufacturers. Its mission is to promote scientific information on responsible management of plant nutrition.

51. Thank You www.ipni.net