Improving Water Use Efficiency in Agriculture · Improving Water Use Efficiency in Agriculture ... China, 27 February – 2 March 2006 Case 1 ... CUMI NG HARLAN LANCAST E PHELPS

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Optimizing Resource Use Efficiency for Sustainable Intensification of AgricultureKunming, China, 27 February – 2 March 2006

Improving Water Use Improving Water Use Efficiency in AgricultureEfficiency in Agriculture

E. J. Sadler E. J. Sadler –– USDAUSDA--ARS Columbia MOARS Columbia MOW. C. Bausch W. C. Bausch –– USDAUSDA--ARS Ft Collins COARS Ft Collins CON. R. Fausey N. R. Fausey –– USDAUSDA--ARS Columbus OHARS Columbus OHR. B. Ferguson R. B. Ferguson –– University of Nebraska, Lincoln NE University of Nebraska, Lincoln NE


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Four Case StudiesFour Case Studies

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Case 1 Case 1 -- Platte River ValleyPlatte River Valley

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Central Platte Natural Resources District Central Platte Natural Resources District Groundwater Management Area (GWMA)Groundwater Management Area (GWMA)

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Kearney

Shelton

GibbonElm Creek

Miller

Riverdale

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LO WER BIG BLU E

LEWI S AND CLARK

PAPIO -MIS SOUR I RIV ER

LOWER P LATTE SOUTH

LOWER P LATTE N ORTH

Reference MapReference Map

Central Platte Natural Resources DistrictGroundwater Quality Management Program


0 - 7.5 ppm#

7.5 - 15 ppm#

Over 15 ppm#

Nitrate Levels (ppm)

Phase I

Phase II

Phase III

Management Areas

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Cent

Shelton

Gibbon

Alda

Cairo

Wood River

St. Libory

Chapman

Archer

HALL

MERRICK

HOWARD

HAMILT

.-,80

(/30

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.-,8 0

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(/30

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HO LT

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LO WER BIG BLU E

LEWI S AND CLARK


LOWER P LATTE SOUTH

LOW ER P LATTE N ORTH




0 - 7.5 ppm#

7.5 - 15 ppm#

Over 15 ppm#

Nitrate Levels (ppm)

Phase I

Phase II

Phase III

Management AreasN

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Island

Central City

Clarks

ibory

Silver Creek

Chapman

ArcherMERRICK

POLK

NANCE

HAMILTON

PLATTE

(/3 4

8 1

(/30

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(/ 14

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(/39

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(/30

CH ER R Y

HOLT

SIO U X

CU ST E R

LIN C OL N

SH ER ID AN

GA RD E N

KN OX

KE ITH

DA WES

ROCK

MOR RIL L

BR OWN

GA GE

CH AS E

DU ND Y

KIM B AL L

GR AN T

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BU FF AL O

HA YE S

LOUP

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BL AIN E

BO YD

FR ON T IER

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BU RT

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BA NN E R

FU RN A S

AR TH U R

TH OM A SHO OKE R

PO LK

LO GA N

SA LIN E

AN TE LOP E

AD AM S

PIE R CE

VA LL EY

DIX ON

BU TL ER

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TH AY ER

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HA RL AN

LA NC AS T ER

PH EL PS

KE YA P AH A

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SE W AR D

NA NC E

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WA Y NE

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WH E EL ER

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RE D W ILL OW

KE AR N EYGOSP E R

ME RR IC K

NU CK O LL S

HA MI LT ON

CO LF AX

SC OT T S B LU F F

PA WNE EJE FF ER SON

NE MA H A

ST AN TON

RIC H AR D SO N

JOHN S ON

SA RP Y

TH UR S TON

DO UGL AS

DA KO T A

WA S HIN G TON

LOW ER L OUP


TWI N P LATTE

NEMA HA


LOW ER E LKHO RN

CENTRA L PLA TTE

LITTLE BLUE

MID DLE REPU BLIC AN

UPPER ELKH ORN

SOUTH PLAT TE

UPPER BI G BLUE

TRI BASI N

LOW ER N IO BRAR A

UPP ER REPUB LICA N


LO WER BIG BLU E

LEWI S AND CLARK


LOW ER P LATTE SOUTH

LOW ER P LATTE N ORTH




0 - 7.5 ppm#

7.5 - 15 ppm#

Over 15 ppm#

Nitrate Levels (ppm)Phase I

Phase II

Phase III

Management Areas

● 0 – 7.5 mg L-1 Phase 1● 7.5 – 12 mg L-1 Phase 2● > 12 mg L-1 Phase 3If no response: Phase 4

Regulation on N fertilizer managementto solve high groundwater N problems

4


Platte Valley Nitrogen and Platte Valley Nitrogen and Irrigation Management Irrigation Management Demonstration ProjectDemonstration Project

Over the life of the project, average values:Expected corn yield 11.0 Mg/haActual corn yield 10.7 Mg/haRecommended N rate 145 kg/haSoil N credit 75 kg/haIrrigation water N credit 31 kg/ha

Over the life of the project, average values:Expected corn yield 11.0 Mg/haActual corn yield 10.7 Mg/haRecommended N rate 145 kg/haSoil N credit 75 kg/haIrrigation water N credit 31 kg/ha


Trends in the Central Platte ValleyTrends in the Central Platte Valley

1985 1990 1995 2000 2005

Irrig

atio

n W

ater

Nitr

ate

N (m

g L-1

)

10

12

14

16

18

20

Soi

l Res

idua

l Nitr

ate

N (l

b ac

re-1

)

60

80

100

120

140

67

90

112

134

157

Soil

Res

idua

l Nitr

ate

N (k

g ha

-1)

5


OhioIndiana

Michigan

Illinois

Wisconsin

Missouri

Iowa

Minnesota

Case 2 - US Corn Belt Region


6


Fertilizer N,kg km-2 year-1

N loss,kg km-2 year-1


US Corn Belt TileUS Corn Belt Tile--Drained LandsDrained Lands

>200,000 km2 in US MidwestSubsurface and surface drainageDocumented loss of nitrate to streamsContributes to Gulf of Mexico hypoxiaPotential to reduce nitrate loss by 30-50%

7


Effect of Controlled Drainage on Effect of Controlled Drainage on Nitrate LossNitrate Loss


Methods to Control DrainageMethods to Control Drainage

8


Louisiana

Arkansas

Missouri

Kentucky

Illinois

Tennessee

New Orleans

Case study 3 Case study 3 -- Lower Lower Mississippi River Valley Mississippi River Valley (LMRV) Delta(LMRV) DeltaAll was cypress swamps, cut for timber in late 1800’s.

Surface drainage was done in early 1900’s.

It has ~70,000 km2 of cropland, with very little other industry.

Approximately half is irrigated.

The LMRV is where new irrigation is being added in the USA.

Alluvial Aquifer is a good irrigation water supply.

Despite that, some areas now have water shortages.

Mississippi


WellRice Field

Irrigation Tubing

Levee

Levee spill

9


Case 4 Case 4 -- Precision Irrigation Precision Irrigation Florence SCFlorence SC

Modified commercial center pivotControl 9-m sections independentlyUsed it to find production functions for water and N for corn


150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

Max Yield Max Profit Max Yield - Max Profit

1999

2000

2001

2 3 4 5 6 7 8 9 10 11 12 13 14

Z = 10.9

Z = 11.1

Z = 12.3

Z = 10.5

Z = 10.6

Z = 12.0

Z = 0.44

Z = 0.50

Z = 0.31

0 1 2 3 4 5 6 7 8 9 1014 Mg/ha2 10 Mg/ha0

Yield

Mg/ha0 14 0 10

10


150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

150 200 250 300 350 400

300

350

400

450

500

550

-20 0 20 40 60 80 100120140160180200220240260280300

Z = 278

Z = 252

Z = 189

Z = 228

Z = 212

Z = 130

Z = 51

Z = 40

Z = 61

0 20 40 60 80 100120140160180200220240260280300300 mm-20 300 mm0

1999

2000

2001

Irrigation Max Yield Max Profit Max Yield - Max Profit

51 mm18%

40 mm16%

61 mm32%

Savings


IWUEkg/ha-mm

10

20

30

40

50

60

0

0 50 100

Scale, mMean = 20.6

135 kg/ha

Mean = 25.3

225 kg/ha

Spatial Irrigation Water Use EfficiencySpatial Irrigation Water Use Efficiencyfor two fertilizer rates on maizefor two fertilizer rates on maize

Florence, SC, data for 2000.

11


Calculated N Use EfficiencyCalculated N Use Efficiency(marginal response to N)(marginal response to N)

YH - YLNUE =

NH - NL

WhereY = yield, kg/haNH = 225 kg/haNL = 135 kg/ha


EconomicBreakevenPoint (1998)

kg corn/kg N

Marginal corn yield benefit from N fertilizer 150% irrigation, 2000

150 200 250 300 350 400

300

350

400

450

500

550

-40-35-30-25-20-15-10-50510152025303540455055


12


kg corn/kg N

Marginal corn yield benefit from N fertilizer 150% irrigation, 2001

150 200 250 300 350 400

300

350

400

450

500

550

-40-35-30-25-20-15-10-50510152025303540455055




ConclusionsConclusions

WUE can be improved• Identify and reduce losses of water• Increase yield

Must address both WUE and fertilizer use efficiency, particularly N• Identify and reduce losses of N (P, K…) • Optimize irrigation with N (P, K…)

Documents

Improving Water Use Efficiency in Agriculture · Improving Water Use Efficiency in Agriculture ... China, 27 February – 2 March 2006 Case 1 ... CUMI NG HARLAN LANCAST E PHELPS