dr. larry c. brown professor, extension agricultural engineer department of food, agricultural, and...
TRANSCRIPT
Dr. Larry C. Brown
Professor, Extension Agricultural EngineerDepartment of Food, Agricultural, and Biological
Engineering
The Ohio State University
Agricultural Water Management [email protected]
http://www.ag.ohio-state.edu/~agwatmgt/
Crop Yields
Subsurface DrainageIntroduction
History, Status
Installation
Design
Crop Yields, BenefitsWater Quality - Hydrologic Effects
Management Techniques
ODNR-DSWC Map
USGS
Ohio Soils and Subsurface
Drainage x x
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WW
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USDA-ARS-SDRU/OSU WTM Research Locations
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Drainage Improvement Economics for Corn & Soybean
Toledo Clay – North Central Ohio
Benefits to Cost Ratio
Corn Soybean
Surface Drainage 3.5 2.1
Subsurface Drain 2.5 1.2
Combination 1.9 1.2
(Based on G.O. Schwab Yield Data from Castalia, Ohio)
Yield AdvantageHoytville Silty Clay – Northwest Ohio
Combination Drainage (S+SSD) Compared to Surface Drainage (No SSD)
(bu/ac)
Continuous Corn 25 to 27Rotation Corn 29Rotation Soybean 7 to 10 (17)
(Based on Brown, Reeder & Eckert Yield Data from OARDC, Wood County)
Drainage Improvement Economics for Corn & Soybean
Hoytville Silty Clay – Northwest Ohio
Benefits to Cost RatioContinuous Corn 1.7 to 2.0Rotation Corn 1.7 to 2.2Rotation Soybean 3.1 to 2.3Notes:Combination Drainage (S+SSD) Compared to Surface
Drainage (No SSD)(Based on Brown, Reeder & Eckert Yield Data from
OARDC, Wood County)
Yield Advantage Hoytville Silty Clay - Combination Drainage (S+SSD) Compared to Surface Drainage (No SSD)
Two Long-Term Drainage-Crop Yield Studies
Toledo Silty Clay
(Schwab et al.)
Hoytville Silty Clay
(Brown et al.)
Continuous Corn 25 to 27
Rotation Corn 29
Rotation Soybean 7 to 10 (17)
(Based on Yield Data from Brown, Reeder & Eckert OARDC, Wood County)
Test Case Simulation• Subsurface Drainage Improvement• Hoytville Silty Clay Soil• Drain Spacings of 15, 30, 45 60, and 100
feet• Range of capital costs from $1133/ac to
$150/ac• Down payment, 40% and 20%• MTR 34% and 40%• Cost of debt, 8% and 10%• Price of corn, means of $2.00 and $2.41• Before- and after-tax analyses
Economics of Drainage Improvements
• Simple Field-Scale Analyses
• More Complex Analyses within Farming Enterprise
• Simulation Modeling
Modeling a Water Balance Midway Between Two Subsurface Drains
Predicting Relative Crop YieldsUsing the
DRAINMOD Water Management Model
Kokomo
0
2
4
6
8
10
12
year
Nu
mb
er o
f d
ays
0
20
40
60
80
100
120
140
160
PP
T(c
m)
PPT(cm) W T less 30 W T less 60 W T less 90
Crosby
0
5
10
15
20
25
Day
0
20
40
60
80
100
120
140
160
PP
T (
cm
)
PPT (cm) WT less 30 cm WT less 60 cm WT less 90 cm
Kokomo Silty Clay Loam – Apparent Water Table, Glacial Till
Crosby Silty Clay Loam – Perched Water Table, Glacial Till
47 Years
Simulation Results
• Optimal spacing 50’
• before-tax analysis
• NPVbt = $928
• Optimal spacing 40’
• after-tax analysis
• NPVat = $818
Water Table Management
• Conventional Drainage
• Controlled Drainage
• Subirrigation
Crop Yields with CWAES @ PRECBrown, Fausey, Bierman, Workman, Subler
156.2
116.6112.7
90.9
114.1121.4
76.9
39.7
0
20
40
60
80
100
120
140
160
180
1995 1996 1997 1998
SI/CD
SSD
Partial-season subirrigation in 1995 and 1998 Full-season subirrigation in 1996 and 1997
7.7 in precipitation during subirrigation period in 199613.1 in precipitation during subirrigation period in 1997
44.6
28.8
54.2
43.1
31.2
24.1
26.528.5
0
10
20
30
40
50
60
1995 1996 1997 1998
SI
SSD
Corn Soybean
Yield Advantage (1996-2001) with Subirrigation/Subsurface Drainage
Shininger Farm – Fulton County, Ohio
• Corn• 192 bu/ac SI/SSD• 140 bu/ac SSD
• Six-Year Average Yield advantage
• 52 bu/ac
• Soybean• 63.6 bu/ac SI/SSD• 53.7 bu/ac SSD
• Six-Year Average Yield Advantage
• 9.9 bu/ac
For soils that are proven to respond to drainage improvements, think about more intensity drainage and
management for potential to produce greater yields:
• Compared to lands with adequate surface drainage,– adding subsurface drainage improvements may
increase yields by 25-30 bu/ac for corn and 3-12 bu/ac for soybean
• Compared to lands with adequate surface drainage,– adding subirrigation may increase yields by 25-
60 bu/ac for corn and 10-12 bu/ac for soybean
Ohio State University/USDA-ARS Crop Yield Data
Dr. Larry C. Brown
Professor, Extension Agricultural EngineerDepartment of Food, Agricultural, and Biological
Engineering
The Ohio State University
Agricultural Water Management [email protected]
http://www.ag.ohio-state.edu/~agwatmgt/
Shininger Farm Ear Comparison (left SI; right SSD)
Photo by Greg La Barge, 2001