Post on 19-Dec-2015
Nitrogen Losses at a Drainage Systems Scale
Bruce MontgomeryMN Department of Agriculture
Red Top Cooperators
UM Dept. of Soil, Water & Climate
Blue Earth Agronomics
Rob & Janice Meyer-Red Top Farms
University of Minnesota Extension
UM Dept of Biosystems and Ag Eng.
Brown Nicollet Environmental Health
And the BNC Water Quality Board
Why do producers error on the high side? “Research is only tested on garden size plots!”
Because most research is developed on small
plots under ideal conditions, many
farmers believe that University
recommendations will not work on production
scale operations
St. Peter Wellhead Protection Area
Community Water Supplies Impacted by Ag
0
2
4
6
8
10
12
14
Year
Nit
rate
-N (
mg
/l)
Well # 6
Well # 9
North Water Plant
South Water Plant
Trend Line
Key Project Goals: Red Top Farm Demonstration
Bridge the gap between UM water quality plot work and farm fields in terms of evaluating nitrogen and pesticide Best Management Practices (BMPs).
Characterize long-term water quantity and quality trends on a field scale using subsurface tile drainage systems.
Develop a demonstration site that is meaningful on a local and a regional scale.
Red Top is Located in Nicollet County, MN
Red Top Field Layout
West Field East Field
Monitoring Equipment at Red Top
Tile Peak Flow Hydrograph June 3 - 8, 2002Total Precip 4.67 in
WE RO 1.69 in EA RO 3.42 inWeir RO 2.47 in (53%) East Field 4.08 in (87%)
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2-Jun 3-Jun 4-Jun 5-Jun 6-Jun 7-Jun 8-Jun 9-Jun 10-JunDate
Dis
ch
arg
e (
cfs
)
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
Pre
cip
ita
tio
n (
inc
he
s/1
5 m
in)
WE Weir (6" Cement Mains) (Max drainage =0.44" in 24 hr)
EA Weir (8" Cement Mains) (Max Drainage = 0.95" in 24 hr)
East Field (8 to 12" Plastic Mains)(Max Drainage = 1.38" in 24 hr)
West Field (EA + WE)
Rainfall
Annual Drainage LossesRed Top Farm 1997-2002
0
5
10
15
20
1997 1998 1999 2000 2001 2002*
Growing Year (Note: 2002 is a partial year)
West Field (total) East Field
An
nu
al D
rain
ag
e L
oss
(In
ch
es)
On average, 7” of drainage or 25% of the annual water
budget is transported.
“Storm Events” account for the majority of the annual drainage
losses
0
2
4
6
8
10
12
14
1998 1999 2000 2001
BaseStorm
58% 74%
76%
An
nu
al D
rain
ag
e L
oss (
Inch
es)
Monthly Distribution of Sub-surface Drainage2000 Growing Season-Red Top
0%
10%
20%
30%
40%
50%
60%
70%
80%
May
June
July
August
Septe
mbe
r
Octob
er
Novem
ber
Decem
ber
Janua
ry
Febru
ary
Mar
chApr
il
Month
Per
cen
t o
f A
nn
ual
Dis
char
ge
Evans (West Field) Dittrich (East Field)2000 2001
Typically, April-May-Early June
account for approximately 75%
of the annual drainage
Nitrogen Fertilizer Application Rates to Corn
168
128
111 114
208
138
115 114
00
50
100
150
200
1995 1997 1999 2001 2002
Corn Growing Year
To
tal N
itro
gen
Rat
e [l
b/N
/acr
e]
West Field East Field
1997 and 1999 N Rate Design
St. Peter Nitrogen Fertilizer Rate Validation Project
2000 and 2001
120
130
140
150
160
0 60 90 120 150
20002001
N Fertilizer Rate (Lb/A) on Corn Following Soybeans
Bu
/ Acr
e
New UM Pub
Midwestern Water Quality Project Symposium
March 11, 2003
Country Inn and Suites
Mankato 9:00-3:00
Improve water quality in the Minnesota River Basin
Midwestern Water Quality Project Minnesota 2000-2002
CAP’s Partners•MN Corn Growers•St. Peter Wellhead Partnership•University of Minnesota•NAICC
Nitrate-N Changes After Implementation of UM BMPs: 1995-
2001N
itra
te-N
Con
cen
trati
on
s (
mg
/L)
05
1015202530
Nitrate-N Changes After Implementation of UM BMPs: 1995-
2001N
itra
te-N
Con
cen
trati
on
s (
mg
/L)
05
1015
2025
30
05
10152025303540
Jun-94 Oct-95 Mar-97 Jul-98 Dec-99 Apr-01 Sep-02Corn-95 Beans-96 Corn-97 Beans-98 Corn-99 Beans-00 Corn-01
Nitrate-N Concentration ConclusionsN
O3-N
m
g/L
iter
Approaching “background
levels” (Corn-Sb rotation with no
nitrogen fertilizer)
Nitrogen Fertilizer Application Rates to Corn
168
128
111 114
208
138
115 114
00
50
100
150
200
1995 1997 1999 2001 2002
Corn Growing Year
To
tal N
itro
gen
Rat
e [l
b/N
/acr
e]
West Field East Field
Nitrate-N Changes –Aggressive N Inputs/Management Changes
Nit
rate
-N C
on
cen
trati
on
s (
mg
/L)
05
1015202530
Red Top Growing Year Average NO3-N Concentration
0
5
10
15
20
25
1995 1996 1997 1998* 1999* 2000* 2001* 2002*Growing Year
*Note: 1998 through 2001 are flow weighted mean concentrations 2002 is a partial year.
NO
3-N
Co
nc
. [
mg
/L]
West Field (total) East Field
Soybeans
CornSoybeans
SoybeansCorn
Corn
Corn
Corn
Nitrate Concentrations by Growing Seasons and Crop
Nitrate-N Concentrations-Entire Monitoring Cycle at Red Top Farms
Nit
rate
-N C
on
cen
trati
on
s (
mg
/L)
0
5
10
15
20
25
30
35
Nitrate-N Losses from Corn and Soybeans 1997-2002
22 21 23
30
9
26
17
43
10
14
0
5
10
15
20
25
30
35
40
45
1997 1998 1999 2000 2001 2002Growing Year
Pounds
of N
itra
te-N
per
Acr
e
West Field East Field
Corn Soybeans CornCornCorn SoybeansSoybeans
Average N Losses: 22 lb/A/year
Total Phosphorus ConcentrationsFlow-Weighted by Growing Seasons
Total Phosphorus Flow Weighted Mean Concentration
0.00
0.05
0.10
0.15
0.20
0.25
GY 1998 GY 1999 GY 2000 GY 2001 GY 2002
Growing Year
Conce
ntr
ati
on (
mg/l
)
Evans (West) Dittrich (East)
Phosphorus (Total) Losses viaSub-Surface DrainageRed Top Growing Year Total Phosphorus Loss
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
1998 1999 2000 2001 2002Growing Year
Tota
l P L
oss
Expre
ssed in
Pounds
per
Acr
e
Evans (West)
Dittrich (East)
Red Top Benefits: Model Calibration
Sands et al, 2003
Sands et al, 2003
Pesticides at a Glance at the Red Top Site
APPLIED to FIELD Metolachlor (Dual) Acetochlor (Surpass) Nicosulfuron (Accent) Imazethapyr (Pursuit) Dicamba (Banvel) Atrazine Glyphosate (Roundup) Trifluralin (Treflan)
DETECTED in TILE WATER Metolachlor (Dual) Acetochlor (Surpass) Nicosulfuron (Accent) Imazathypyr (Pursuit) Dicamba (Banvel) Atrazine
Seven Mile Creek Watershed Characteristics
85% of the watershed is cropland-mostly prime;
Very high % tile drained;
Documented water quality challenges
Seven Mile Creek High Nitrogen Loading Minor Watershed
49.33
39.41
13.65
1.23 2.19 1.43 0.720.291.22
13.69
7.29
1.05
7.20
27.68
0
10
20
30
40
50
60
Dutch SevenMile
Bevens Chaska Carver Riley Credit Willow NineMile
Nit
rate
-N Y
ield
(lb
s/ac
re)
2000
2001
Seven Mile Creek Significant Phosphorus Loading Minor Watershed
1.65 1.64
1.25
1.11
0.28 0.29
0.34
0.040.07
0.200.14
1.15
0.74
0.34
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
1.60
1.80
Dutch SevenMile
Bevens Chaska Carver Riley Credit Willow NineMile
TP
Yie
ld (
lb/a
cre)
2000
2001
Red Top and Seven Mile Creek Nitrate-N “Runoff”: 2000-2001
3.9
9.7
3.8
13.4
3.5
16.6
0
2
4
6
8
10
12
14
16
18
2000 2001Year
Inch
es o
f R
un
off
West Field
East Field
Seven Mile Creek Site 3
Red Top and Seven Mile Creek Nitrate-N Concentrations: 2000-2001
13.5
12.2
14.5
12.2
16.8
10.5
0
2
4
6
8
10
12
14
16
18
2000 2001Year
Co
nce
ntr
atio
n (
mg
/l)
West Field East Field Seven Mile Creek Site 3
Field (Red Top) vs Watershed Scale (Seven Mile Creek) Nitrate-N Losses
0
5
10
15
20
25
30
35
40
45
2000 2001Year
Nit
rate
-N L
each
ing
Lo
sses
(lb
s/ac
re)
West Field
East Field
Seven Mile Creek Site 3
Field (Red Top) vs Watershed Scale (Seven Mile Creek) Nitrate-N Losses
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
2000 2001
Lbs/
Acr
e/In
ch o
f Run
off
Red Top (Both Fields)
Seven Mile
Due to the flashy drainage characteristics of these systems, continuous automated monitoring is absolutely critical!
The majority of the drainage and chemical movement occurs in very narrow timeframes.
Red Top Farm Demonstration Drainage and Response Times
Implementation of existing Nitrogen BMPs and University of Minnesota Fertilizer Recommendations resulted in a significant reduction in fertilizer inputs (25-30%), maintained yields and appears to have decreased N losses at this site by 40-50%.
Field scale Nitrogen strip validation work both at Red Top and within the St. Peter Source Water Protection Area continued to demonstrate that the UM Fertilizer Recommendations will optimize yields.
Red Top Farm Demonstration Nitrogen Management Conclusions
General Observations based on the First 5 Years at Red Top
Expect to see annual N LOSSES between 15-25 Lb/A under well managed corn-soybean production;
Unlikely that the 10 mg/L drinking water standard can be attained under corn-soybean rotations.
Red Top Farm DemonstrationNitrogen Losses in a Nutshell
Assuming that nitrate-N levels of 13-15 mg/Lunder a corn-soybean rotation are “backgroundlevels”, this means the following:
1) For every inch of drainage water, there is3.2 pounds of N loss; (simply calculated bydividing the concentration by the magic number Of 4.4. In this case 14 mg/L divided by 4.4=3.2)
2) Furthermore, since the average annual drainage is 7”, this means that 22 lb/A is losteach year.
Red Top Farm Demonstration Nitrogen Management Conclusions
The biggest water quality improvements will be realized through the implementation of basic nitrogen management such as correct rate selection and timing of application.
Monitoring tile drainage systems is a practical methodology for verifying effectiveness of Best Management Practices on a field-scale.
This system is an excellent educational tool for developing the linkage between ag practices and water quality issues.
Red Top Farm Demonstration General Conclusions
For more information from MDA Staff……..
Bill VanRyswyk-Surface Water Hydrologist, Mankato 507-389-5772
Brian Williams-Advisor, Le Sueur 507-665-6806
Paul Wotzka-Surface Water Hydrologist, Elba (Whitewater State Park) 507-932-5424
Bruce Montgomery-Unit Supervisor, St. Paul 651-297-7178