Using Paired Edge‐of‐Field Data to Assess Impacts of Management on Surface and Subsurface P Loss

Kevin W. King, Mark R. Williams, and Norm R. FauseyUSDA‐ARS

Soil Drainage Research UnitColumbus, OH

Edge-of-field research

40 fields (20 paired fields) representative of Ohio crop production agriculture

Surface runoff and tile discharge measurements

Using a before-after control-impact study design

4R Research FundUSDA‐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

Even

t mea

n co

ncen

trat

ion

(mg/

L)

0.0

0.5

1.0

1.5

2.0

2.5surfacetile

DRP TP

Phosphorus Concentrations 

Ann

ual D

RP

load

ing

(kg/

ha/y

r)

0.00.20.40.60.81.01.21.41.61.82.02.22.42.62.83.03.23.4

TileSurfaceP Tack Force recommendation

Ann

ual T

P lo

adin

g (k

g/ha

/yr)

0.00.20.40.60.81.01.21.41.61.82.02.22.42.62.83.03.23.43.63.84.0

A B C D E F G H I J K L M N O P Q

0.0

0.2

0.4

0.6

0.8

1.0Discharge

Frac

tion

of A

nnua

l

0.0

0.2

0.4

0.6

0.8

1.0DRP

Event Size (mm)

0.0

0.2

0.4

0.6

0.8

1.0TP

<12.7

12.7-25

.425

.4-38.1

38.1-

50.850

.8-63

.5

63.5-

76.2

76.2-88

.9

> 88.9

Effect of event size on surface losses

2094 rainfall events greater than 6.3 mm (0.25 inches)

Across all sites, rainfall events > 50.8 mm (2 inches) accounts for:

• 10.2% of all rainfall events

• 65% of discharge

• 64% of DRP load

• 65% of TP load

0.0

0.2

0.4

0.6

0.8

1.0Discharge

Frac

tion

of A

nnua

l

0.0

0.2

0.4

0.6

0.8

1.0DRP

Event Size (mm)

0.0

0.2

0.4

0.6

0.8

1.0TP

<12.7

12.7-25.4

25.4-38.1

38.1-50.8

50.8-63.5

63.5-76.276.2-88.9

> 88.9

Effect of event size on tile losses

1601 rainfall events greater than 6.3 mm (0.25 inches)

Across all sites, rainfall events > 50.8 mm (2 inches) accounts for:

• 6% of all rainfall events

• 45% of discharge

• 33% of DRP load

• 33% of TP load

4R Preliminary FindingsRate Timing

PlacementSource

Fertilizer Rate

Discharge:Precipitation Ratio0.0 0.2 0.4 0.6 0.8 1.0

Meh

lich

3 ST

P (p

pm)

0

2040

6080

100120

140

160

180

300400500

<0.3 kg/ha>0.3 kg/hatri-state critical leveltri-state maintencance level

Fertilizer Rate

3/1/15 4/1/15 5/1/15 6/1/15 7/1/15 8/1/15 0

500

1000

1500

2000

2500

DR

P (m

g/L)

0.0

0.1

0.2

0.3

0.4

Dis

char

ge (m

3/s)

0

500

1000

1500

2000

2500

NO

3 +

NO

2 - N

(mg/

L)

0

5

10

15

20

discharge

Data from Heidelberg Univ.Laura Johnson

Timing

Time of Application

• Greatest potential for surface and tile losses occurs with fall and winter application

• Applying P in spring or after wheat harvest seems to minimize surface and tile losses

Meh

lich

3 ST

P (p

pm)

0

20

40

60

80

100

120

140

160

180

Time of applicationJan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan

0

20

40

60

80

100

120

140

160

180

Surface Losses

Tile Losses

0.56 kg/ha 0.50 kg/ha0.04 kg/ha

0.50 kg/ha0.06 kg/ha

Days since application0 20 40 60 80 100 120 140

DR

P co

ncen

trat

ion

(mg/

L)

0

5

10

15

20

1/3/12: 225# MAP11/13/13: 193# MAP

Placement

Broadcast variable rate application on May 6, 2014

4‐part stratification

• Stratification evident even in the top 1” of soil (ANOVA, P<0.001, n=232)

• Although the degree of stratification varied some…  • 85% of the samples had some degree of stratification 

M3P (ppm)

0 25 50 75 100 125 300

Cor

e de

pth

(inch

es)

0-1

1-2

2-5

5-8

Median

60

49

34

26

54.5

Source: Johnson and Baker, Heidelberg University

0

20

40

60

80

100

120

140

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

0 10 20 30

0.00

1.00

2.00

3.00

4.00

5.00

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

0 20 40 60 80

DischargePreferential flowDRP

Dis

char

ge (m

m)

Before P application & tillage (April 28th)

DR

P (m

g/L)

TD1 TD2

0

20

40

60

80

100

120

140

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

0 20 40 60 80

DischargeDRP

DR

P (g

/ha)

After P application & tillage (May 12th)

0.0

1.0

2.0

3.0

4.0

5.0

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

0 10 20 300.0

1.0

2.0

3.0

4.0

5.0

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

0 10 20 30

TD1 TD2

0

20

40

60

80

100

120

140

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 20 40 60 80

0.0

1.0

2.0

3.0

4.0

5.0

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 20 40 60 80

0

20

40

60

80

100

120

140

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

0 10 20 30

Avg DRP (mg/L) =0.08 Avg DRP (mg/L) =0.08 Avg DRP (mg/L) =0.58 Avg DRP (mg/L) =2.12

DRP Load (g/ha) = 12.6 DRP Load (g/ha) = 12.4 DRP Load (g/ha) = 18.2 DRP Load (g/ha) = 129.6

DR

P (m

g/L)

DR

P (g

/ha)

Fertilizer Source

DR

P Lo

ad (k

g/ha

)

0.0

1.0

2.0

3.05.05.56.0

DRPN

O3-

N L

oad

(kg/

ha)

0102030405060708090

100110120

NO3-N

inorganic mixed organic

Fertilizer Source (chronic vs acute risk)

Structural and Other Management

Gypsum

Cover Crops

Drainage Water Mgt

Drainage Water Management

Quantify tile discharge and nutrient dynamics before and after implementation of drainage water management

Drainage area:B2 = 14 ha; B4 = 15 ha

Tile depth:0.9 - 1.0 m

Soil type:Bennington silt loamPewamo clay loam

Soil test P concentration:60 mg/kg (0-20 cm)

2006-2008: Both sites were free draining2009-2012: DWM was implemented at B4

B2

B4

0 90 180 m

Ditch

Legend

Tile outletDrainage area

Upper Big Walnut Creek

Watershed

Ohio

DWM - Case Study

0.00

0.05

0.10

0.15

0.20

0.25

0.30

2005.520062006.520072007.520082008.520092009.520102010.520112011.520122012.5

Mea

n D

RP

conc

. (m

g L-

1 )

Year

B2

B4

0.00

0.30

0.60

0.90

1.20

2006 2007 2008 2009 2010 2011 2012

Year

Ann

ual D

RP

load

(kg/

ha)

DWM did not significantly affect DRP concentration65-74% reduction in annual DRP load with DWM

DWM - Case Study

Gypsum Treatment

• Mercer County Ohio 

• >400 ppm Mehlich 3 in the top 8 inches

• Corn‐soybean rotation in a no‐till system

• Blount soil; randomly tiled 

• June 2011 to October 2014

• October 3 of 2013, 1‐ton of gypsum was applied to treatment area 

• Baseline period (86 rainfall events )

• Treatment period (34 rainfall events)

0.0 0.5 1.0 1.5 2.0 2.50.0 0.5 1.0 1.5 2.0 2.5

DR

P co

ncen

tratio

n (m

g/L)

0.0

0.5

1.0

1.5

2.0

2.5

0.0 0.1 0.2 0.3 0.4 0.5

DR

P lo

ad (k

g/ha

)

0.0

0.1

0.2

0.3

0.4

0.5

0.0 0.1 0.2 0.3 0.4 0.5

0.0 1.0 2.0 3.0 4.0 5.0

TP c

once

ntra

tion

(mg/

L)

0.0

1.0

2.0

3.0

4.0

5.0

kn4-tp-cnc-c vs kn1-tp-cnc-c kn4-tp-cnc-t vs kn1-tp-cnc-t xp vs surf TP conc c xp vs surf TP conc t

0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0

0.0 0.1 0.2 0.3 0.4 0.5

TP lo

ad (k

g/ha

)

0.0

0.1

0.2

0.3

0.4

0.5

kn4-tp-ld-c vs kn1-tp-ld-c kn4-tp-ld-t vs kn1-tp-ld-t xp vs surf TP load c xp vs surf TP load t

0.0 0.1 0.2 0.3 0.4 0.5 0.0 0.1 0.2 0.3 0.4 0.5

Trea

tmen

t fie

ld

0.0 0.5 1.0 1.5 2.0 2.5

0.0 0.1 0.2 0.3 0.4 0.5

Control field

Surface Tile Combined

Gypsum effect on surface drainage and P

• Significant increase in tile drainage discharge

• Significant decrease in DRP and TP event concentrations

• Significant decrease in DRP and TP loading

Cover Crops (what is the resource concern?)Positives

Increase infiltration

Reduce erosion 

Improve soil health

Increase OM

Negatives

Increase DRP surface losses following freeze thaw cycles (Miller et al., 1994; Bechmann, et al 2005; Cavadini, 2013)

Leachate concentrations of P differ depending on catch crop and soil  (Riddle and Bergstrom 2013; Liu et al 2014)

P concentration around tuber of tillage radish significantly greater than surrounding soil (White and Weil, 2011)

P & N losses are impacted by:

STP

Connectivity to water

Placement of P fertilizer

Timing of fertilizer

Rate of fertilizer

Source and legacy effects

Conclusions

Practices that will address excess P

Adherence to tri‐staterecommendations or lesser application

Increased organic matter/carbon, cover crops, no‐till, etc

Avoiding fall and winter applications

Accounting for manure in nutrient calculations

Subsurface placement of nutrients (banding or injecting)

Disconnecting hydrologic pathways (DWM, blind inlets, linear wetlands, water storage/increased OM)

Conclusions

Cover crops – correct cover crop or blend is critical

Gypsum –water quality benefits  are minimal but significant

Collaborators, Partners, and Outreach• SWCDs• OSU Extension and OARDC• Agri‐businesses (Commodities, retailers)• Ohio Farm Bureau• TNC• State agencies (ODNR, ODA, OEPA)• NRCS (local, state, and federal)• Crop consultants• Producers/landowners• Lake Improvement• Other ARS locations• NOAA and NWS• Great Lakes Commission• Great Lakes Protection Fund

• Greenleaf Advisors• Multiple University Partners • (OSU, Utoledo, Oklahoma State 

Univ., Univ. of Waterloo, NC State, Purdue Univ.)

• 4R Research Fund (IPNI, TFI)• NCWQR at Heidelberg• Agriculture and Agri‐Food Canada• Consultants (CCAs, Limno‐Tech)• USGS• Private Industry (Agri‐Drain, ADS, 

Hancor, John Deere, The Andersons, Becks Hybrids)

• Gypsoil

Contact Information

Kevin King590 Woody Hayes Dr.Columbus, OH 43210

kevin.king@ars.usda.gov

Technical Support StaffMark Day, Eric Fischer, Phil Levison, Paxton  MacDonald, Katie Rumora, Marie Schrecengost, Jed Stinner