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