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