sustainable high yields on poorly drained soils
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Sustainable High Yields
on Poorly Drained Soils
For presentation:Water for Food Conference Lincoln, NebraskaMay 1-3, 2011
R. Wayne Skaggs
Drainage in United States (Million Ha)
Total Cropland 170
Cropland Requiring Drainage 43 (25%)
Cropland NeedingDrainage 500 Million Ha
(33% of Total Cropland)
DRAINAGE WORLD-WIDE
(Smedema et al. 2004)
Million HaAll Cropland 500 (33%)
Irrigated Cropland 150 (55%)
Rainfed Cropland 350 (28%)
CROPLAND NEEDING DRAINAGE (Smedema et al. 2004)
Avg. annual nitrogen yield Mississippi River of streams for 1980-1996 Drainage Basin Hypoxic Zone
Nitrogen Losses in Drainage Water Increase with Intensity of Subsurface Drainage
0
5
10
15
20
25
30
35
40
45
Natural Slow Dr. Moderate Intensive
Total Nitrogen (kg/ha/yr)
TOTAL NITROGEN
3.6
13.6
20.0
42.1
-180
-160
-140
-120
-100
-80
-60
-40
-20
0
0 50 100 150 200 250 300 350 400
Day of Year, 1974
Wa
ter
Ta
ble
De
pth
, c
m
Drainage
Controlled Drainage
Weir Depth
DWM Structures for DWM Structures for Subsurface DrainsSubsurface Drains
Drain Drain Control Percent ReductionReference Location Soil Area Spacing Depth Depth* Drainage N Loss
(ha) (m) (m) (m)______________________________________________________________________________________________________________________________________Gilliam et al. (1979) N. Carolina Portsmouth sl 5 to 16 30 & 80 1.2 0.3-0.5 50 50
N. Carolina Goldsboro sl 3 30 1 0.3 85 85Evans et al. (1989) N. Carolina Ballahack sl 4 18 1 0.6 56 56
N. Carolina Wasda muck 4 100 1.2 0.6 51 56N. Carolina Wasda muck 4 18 1 0.6 17 18
Lalonde et al. (1996) Ontario Bainesville sil 0.63 18.3 1 0.75 49 690.5 80 82
Tan et al.(1998) Ontario Brookston cl 2.2 9.3 0.65 0.3 20 19Drury et al., 2008 Ontario Brookston cl 0.1 7.5 0.6 0.3 29** 31 - 44***Wesstrom et al. (2007) Sweden Loamy Sand 0.2 10 1 0.2-0.4 80 80Fausey (2005) Ohio Hoytville sic 0.07 6 0.8 0.3 41 46
* Controll typically removed during seedbed preparation, planting, and harvesting periods. **CD reduced subsurface drainage by 29%, increased surface runoff by 38% & reduced total outflow by 10.6%*** CD reduced N loss by 44% for recommended N application rates and by 31% for elevated N rates
Potential Effect of DWM in the Midwest on N Load to Gulf of Mexico
• 50,000 ton N per Year
• Based on 8.3 million Ac of drained corn and soybean land in the states of Iowa, Indiana, Illinois, Ohio and Minnesota (Jaynes et al., 2008)
• NRCS recently (March, 2011) announced a major initiative to promote DWM and related practices in the upper Midwest to reduce N losses to the Mississippi River and Gulf of Mexico.
Agrosphere
AMPLIFY is a initiative enabling public and private sector scientists to partner with producers to achieve high yield in an environmentally and economically sustainable manner.
AMPLIFY
Modeling for
Producing Large Increases
in Food Yield
Potential to Increase Sustainable Yields on Drained Soils in Humid regions
Effect of Drain Spacing on Average Predicted Corn Yield Portsmouth Sandy Loam, Plymouth, NC
20
30
40
50
60
70
80
90
100
0 10 20 30 40 50 60 70 80 90 100
Drain Spacing, m
Re
lati
ve
yie
ld,
%
Predicted Relative Corn Yield, Drained Portsmouth soil, Plymouth, NC
0
20
40
60
80
100
120
Years
Rela
tive Y
ield
(%
) Avgerage Yield= 77% of Potential)Poor Drainage, Avg Yld=55%
Effect of Drain Spacing on Average Predicted Corn Yield Portsmouth Sandy Loam, Plymouth, NC
20
30
40
50
60
70
80
90
100
0 10 20 30 40 50 60 70 80 90 100
Drain Spacing, m
Re
lati
ve
yie
ld,
%
23%
Predicted Relative Corn Yield, Drained Portsmouth soil, Plymouth, NC
0
20
40
60
80
100
120
Years
Rel
ativ
e Y
ield
(%
)
Avgerage Yield= 77% of Potential)
60
70
80
90
100
0 0.5 1 1.5 2 2.5
Irrigation Amt/Application, cm
Re
lati
ve
yie
ld, %
0
5
10
15
20
25
An
nu
al W
ate
r U
sag
e, cm
Yield
Irr. Water used
Predicted Relative CornYields With and W/O Irrigation
0
20
40
60
80
100
120
Years
Re
lati
ve
Yie
ld (
%)
No Irrigation (Avg.= 77%)With Irrigation (Avg.=97.7%)
Predicted Annual NO3-N Losses to Surface Waters, Continuous Corn
0
20
40
60
80
100
Years
kg
/ha
Conventional Drainage (41.7 kg/ha)Conv. DR with Irrigation (28.5 kg/ha).
Effect of Root Depth on 35-Yr Average Predicted Corn Yield
60
70
80
90
100
30 35 40 45 50 55 60 65 70 75 80
Maximum Effective Root Depth, cm
Re
lati
ve
yie
ld, %
Effect of Root Depth on Predicted Relative Corn Yields
0
20
40
60
80
100
120
Years
Rela
tive Y
ield
(%
)
Root Depth 30 cm (Avg.= 77%)Root Depth 60 cm (Avg. = 92%)
Hypothesis
Drought stresses can be substantially reduced and yields increased by increasing root depths in poorly drained soils in humid regions
Methods to Increase Root Depth
• Increase pH to > 5.5 to depths of > 60 cm
• Incorporate Organic Matter
• Genetic Manipulation
Effect of Root Depth on 35-Yr Average Predicted Corn Yield
40
50
60
70
80
90
100
30 35 40 45 50 55 60 65 70 75 80
Maximum Effective Root Depth, cm
Rela
tive y
ield
, %
PLYMOUTH, NC
JACKSONVILLE, FL
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