Tom Bruulsema, Vice President, Americas & Research, International Plant Nutrition Institute

Industry Initiatives Addressing Phosphorus Challenges

St. Louis, Missouri27 July 2017

The International Plant Nutrition Institute is supported by leading fertilizer manufacturers.

Its mission is to develop and promote science for responsible management of crop nutrition.

Outline – Industry Initiatives Addressing P

1. Sustainability Perspectives

– Ecosystem services

– Global stocks and flows

2. Lake Erie Watershed

– Phosphorus Loads and Harmful Algal Blooms

– 4R Research Project

3. 4R Phosphorus Practices

– A first step toward a metric for impact on water quality

http://phosphorus.ipni.net/

Phosphorus Sustainability Perspectives

• Food industry

– Needs clear simple metrics of sustainability impact

• Producers

– Burden of sustainability reporting requirements

• Scientists

– Management impact on P loss too complex to quantify

– Lack of consensus on metrics and material flows

Ecosystem ServicesFood-fiber-fuelNutrient cycling

C storageWater retention

Landscape aesthetic

Impacts of PCrop productivity

BiodiversityWater quality

FishRecreation

Property value

Adapted from MacDonald et al 2017

Figure from Macintosh, Withers, et al. (in preparation)Data from New Zealand irrigated pastures (McDowell and Condron2012; Condron et al. 2012; Rickard and McBride 1986)

Trade-offs among multiple ecosystem services: would optimum soil test P increase or decrease?

Yield

% Clover

P Loss

Soil Carbon

4R Phosphorus for Sustainable Crop Nutrition

Actions(adoption metrics)

Key Outcomes(impact metrics)

1. Farmland productivity

2. Soil health

3. Nutrient use efficiency

4. Water quality

Soil health metric: soil test P ranges widely. Levels declining over past 15 years.

Phosphorus sample distribution: 10 states centered on Missouri

soiltest.ipni.net

Measured losses from well-managed fields are no more

than a few % of P applied

Sharpley et al., 2016. Better Crops 100(3):13-15.

Global P material flow analysis

Cordell & White, 2014

PUE: 19% (3.5/18)

Loss ratio:[2009] 46%[here] 28% [Bouwman et al., 2009] 14% (fert only) or 6% (all inputs)

5±3 Tglosses

Watershed scale: Maumee River

River export: 5-20% of fertilizer input

Powers et al., 2016. Nature Geoscience 9(5):353-356.

Lake Erie – both dissolved and particulate P loads are important.

Terra MODIS Direct Broadcast Images 7 May 2017

Western Lake Erie: dissolved P trends increasing since 2002

Jarvie et al., 2016, J Environ. Qual.

Cu

mu

lati

ve D

RP

load

(kg

P2O

5 h

a-1)

0

4

8

2

16

2

0

0.8 kg P2O5

ha-1 y-1

0.4 kg P2O5 ha-1 y-1

Soil Drainage Research Unit

4R Research Fund USA-4RN09USDA-ARS: USDA-Agriculture Research ServiceCEAP: Conservation Effects Assessment ProjectEPA: DW-12-92342501-0Ohio Agri-BusinessesOhio Corn and Wheat Growers

Funding Sources:

CIG: 69-3A75-12-231 (OSU)CIG: 69-3A75-13-216 (Heidelberg University)MRBI: Mississippi River Basin InitiativeThe Nature ConservancyBecks Hybrids/Ohio State UniversityOhio Soybean Association

Kevin King, USDA-ARS, Columbus, Ohio

4R Research Fund: Lake Erie Watershed ProjectMonitoring P loss at edge of field & in stream

Lake Erie Watershed 4R Research – key findings to date1. Right Place: Incorporation of broadcast fertilizer

reduced P loss in tile drains by 45% and peak dissolved P concentrations by up to five-fold

2. Right Time: Fertilizer applied during the summer and early fall (June through October) resulted in the least potential for P loss compared to other periods of the year

3. Farmers express concern for their impact on the lake, and up to 90% are willing to change practices.

4. Collaborating brings rewards.

http://research.ipni.net/project/IPNI-2014-USA-4RN09

http://phosphorus.ipni.net/

Participating Scientists 1. Brian Arnall, Oklahoma State U2. Doug Beegle, Penn State U3. Don Flaten, U of Manitoba4. Laura Good, U of Wisconsin5. Kevin King, USDA-ARS, Columbus, OH6. Quirine Ketterings, Cornell U7. Josh McGrath, U of Kentucky8. Antonio Mallarino, Iowa State U

9. Rao Mylavarapu, U of Florida with input from other colleagues.

10. David Mulla, U of Minnesota11. Nathan Nelson, Kansas State U12. Keith Reid, Agriculture and Agri-

Food Canada13. Nathan Slaton, U of Arkansas -

with input from Bruce Linquist, UC-Davis, Bobby Golden, Mississippi State U, Dustin Harrell, Louisiana State U.

14. Charles Shapiro, U of Nebraska15. Andrew Sharpley, U of Arkansas16. Doug Smith, USDA-ARS, Temple,

TX17. Ivan O’Halloran, U of Guelph18. Deanna Osmond, North Carolina

State U19. David Tarkalson, USDA-ARS,

Kimberly, ID - with input from Bryan Hopkins, Brigham Young U, and others.

Regions and Cropping Systems

2011 National Land Cover Database - http://www.mrlc.gov

1

5

4

3

2

1. Eastern Cereals and Oilseeds

2. Western Corn and Soybean

3. Wheat in the Great Plains

4. Irrigated Potatoes in the Northwest

5. Rice

Basic 4R Phosphorus Practices for Western Corn and Soybean (NE, ND, SD, MN, KS, MO, IL, IA, WI)

• Right Source

– All sources applied have known or guaranteed analysis.

– Manures are applied using current nutrient analysis or current book values.

• Right Rate

– Rates are based on current soil tests using recognized sampling and analytical procedures, and recognized evidence-based recommendations.

– All P sources are accounted for.

– Application equipment is maintained and calibrated.

– Current soil tests are taken within the last 4 years.

– For recommendations using an expected yield approach, expected yield is calculated using average of last 4-6 years of production levels plus regional trend line projection.

– For manure, application rate is based on P-Index or other recognized transport risk assessment.

Basic 4R Phosphorus Practices for Western Corn and Soybean (NE, ND, SD, MN, KS, MO, IL, IA, WI)

• Right Time

– Applications are not made when soils are frozen or snow covered unless based on recognized guidelines.

– P is not applied without incorporation when it is likely that rainfall or irrigation resulting in runoff will occur in next 48 hours.

• Right Place

– Banding or injecting below the soil surface is encouraged.

– Where P is broadcast, it is either incorporated into the soil before runoff occurs, or, for zero-till, P may be surface applied if the P Index or other recognized risk assessment tool indicates low risk of P loss.

– Neither fertilizer nor manure is applied to grassed waterways or other concentrated flow channels.

Intermediate 4R Phosphorus Practices for Western Corn and Soybean (NE, ND, SD, MN, KS, MO, IL, IA, WI)

• Right Source

– As in basic, plus:

– Manures have farm-specific nutrient analyses using recognized sampling procedures.

• Right Rate

– As in basic, plus:

– Where the recognized recommendation for rate is zero, no P is applied unless using manure AND there is low probability for P loss based on the P-Index or similar tool, OR the P is applied as starter at a rate substantially below expected crop removal.

– Soil test P is maintained at or below the level above which no P is recommended.

– A risk assessment tool, like the P Index, is used in an integrated plan for managing nutrients.

• Right Time

– Applications are not made when soils are frozen or snow covered.

– P is applied when there is a lower risk of loss due to runoff, considering seasonal rainfall intensity and other factors included in risk assessment tools like the P Index.

• Right Place

– As in basic, plus:

– P sources are not applied to the furrows of furrow-irrigated crops.

– Uniformity of spreader pattern and application rate are verified.

Intermediate 4R Phosphorus Practices for Western Corn and Soybean (NE, ND, SD, MN, KS, MO, IL, IA, WI)

Advanced 4R Phosphorus Practices for Western Corn and Soybean (NE, ND, SD, MN, KS, MO, IL, IA, WI)

• Right Source

– As in intermediate.

• Right Rate

– As in intermediate, plus:

– Fields are subdivided to receive zone-specific rates.

– Current soil samples are taken at least every two years using recognized recommendations for grid or management zone sampling density and use of auxiliary information.

– Soil sampling protocol accounts for stratification and bands.

– Spatial patterns in soil test results and crop yield maps are used to guide variable rate application.

• Right Time

– As in intermediate.

• Right Place

– As in intermediate, plus:

– Areas with potential to contribute high levels of P to the environment are identified using digital terrain analysis or other landscape assessment tool, and recognized guidelines for managing such areas are followed.

Advanced 4R Phosphorus Practices for Western Corn and Soybean (NE, ND, SD, MN, KS, MO, IL, IA, WI)

4R efficacy for reducing P loss, % reduction

1. Wide range of efficacies demands more site-specific focus.

2. Trade-off between dissolved and particulate is important.

Practice Dissolved P Particulate P

Source --- ---

Rate 60 to 88% negligible

Time 41 to 42% negligible

Place 20 to 98% -60% to NS

Soil inversion NS to 92% -59% to NS

Conservation tillage -308 to -40% -33 to 96%

- ranges found in field experiments across the USA and Canada

Dodd & Sharpley, 2015. Nutrient Cycling in Agroecosystems.

So what role can Precision Ag and ICT play to improve phosphorus sustainability?

• Tools for right place and right time

• Translate practices to performance

• Risk assessment tools:

–Farmer self-assessment

–Third party assessment

–Field Print Calculator – STEP, APEX, SWAT?

–Quantification of P loss reduction

Summary

• A wide range of sustainability perspectives can be addressed if metrics are chosen carefully and reported on consistently.

• 4R nutrient stewardship can reduce losses of dissolved phosphorus and optimize soil available phosphorus levels.

• Soil conservation practices are still important for managing particulate losses.

• Quantification of practice impacts on phosphorus losses is important to enabling sustainability investment decisions.