peach tree et - utah state university extension · peach tree et horticulture association...
TRANSCRIPT
Peach Tree ET
Horticulture Association Convention
Spanish Fork, Utah
January 22, 2015
Presentation by
L. Niel Allen
Extension Irrigation Engineer
Plant Evapotranspiration
ET equations (energy basis, 540 calories to evaporate 1
gram of water):
Solar Radiation
Temperature
Humidity
Wind
Plant Photosynthesis
Carbon dioxide + water +
light energy →
carbohydrate + oxygen
0.04 percent CO2 in the
air
Plants open Stomata to
get CO2
Plant transpire water
when Stomata are open
Surface AirOver 500 times more oxygen than CO2 in the air.
0
10
20
30
40
50
60
70
80
90
N2 O2 Ar CO2 Ne He CH4
Per
cen
t
Gases in the Earth's Atmosphere
Trace Gases
Gas Volume(A)
Name Formula % by volume
Nitrogen N2 78.084
Oxygen O2 20.946
Argon Ar 0.9340
Carbon dioxide CO2 0.0397
Neon Ne 0.001818
Helium He 0.000524
Methane CH4 0.000179
Not included in above dry atmosphere:
Water Vapor H2O 0.001%–5%(D)
Vapor Pressure at Saturation in the Air
The amount (capacity)
of water vapor that air
can hold.
Primarily a function
of temperature
The sum of the
individual gas pressure
is the total
atmospheric pressure
Surface atmospheric
pressure is about 100
kPa
0
2
4
6
8
10
12
14
32 50 68 86 104 122
Vap
or
Pre
ssu
re (
kP
a)
Temperature Fº
Using Vapor Pressure Deficit to Estimate ET
Hypothesis: The Vapor Pressure Deficit of the air in an
orchard can be used to estimate peach tree ET.
Reasoning: Vapor Pressure Deficit is a function of
temperature and humidity; and temperature is related
to solar radiation.
Data: Hourly ET of peach trees from two large
weighing lysimeters (1988-2004).
Data: Complete set of hourly climate data (1988-2004)
Experimental Site Information
UC Kearney Agricultural Center near Parlier, California
Two weighing lysimeters (2m x 4m x 2m deep, two trees
per lysimeter, drip irrigated, hourly reading, ±0.001
inch/day)
Peach Trees (16-ft row x 6-ft spacing, trees outside of
lysimeter are irrigated with micro sprinklers)
Variety: O’Henry (1988-1997), Crimson Lady (1999-
2004)
Lysimeters located in center of 2.5 acre plot
Water use by drip-irrigated late-season peachesJ. E. Ayars, R. S. Johnson, C. J. Phene, T. J. Trout, D. A. Clark, R. M. Mead
Irrigation Science 22.3-4 (2003): 187-194.
Water use by drip-irrigated late-season peachesJ. E. Ayars, R. S. Johnson, C. J. Phene, T. J. Trout, D. A. Clark, R. M. Mead
Irrigation Science 22.3-4 (2003): 187-194.
Additional Analysis
Temperature (some of first equations Blaney-Criddle)
Solar Radiation and Temperature (Hargreaves Samani)
Humidity and Wind (Penman equations)
-
0.20
0.40
0.60
0.80
1.00
1.20
100 400 700 1000 1300 1600 1900 2200 100 400 700 1000 1300 1600 1900 2200
No
rmali
zed
Valu
es
Hour of Day
Hourly Peach ET v Solar Radiation
June 29-30, 1994
Solar Lysimeter ET
June 29 ET 0.30 inches
June 30 ET 0.28 inches
-
0.20
0.40
0.60
0.80
1.00
1.20
100 400 700 1000 1300 1600 1900 2200 100 400 700 1000 1300 1600 1900 2200
No
rmali
zed
Valu
es
Hour of Day
Hourly Peach ET v Air Temperature
June 29-30, 1994
Air Temp Lysimeter ET
June 29 ET 0.30 inches
June 30 ET 0.28 inches
-
0.20
0.40
0.60
0.80
1.00
1.20
100 400 700 1000 1300 1600 1900 2200 100 400 700 1000 1300 1600 1900 2200
No
rmali
zed
Valu
es
Hour of Day
Hourly Peach ET v Vapor Pressure Deficit
June 29-30, 1994
Vapor Pressure Deficit Lysimeter ET
June 29 ET 0.30 inches
June 30 ET 0.28 inches
-
0.20
0.40
0.60
0.80
1.00
1.20
No
rmali
zed
Valu
es
Hour of Day
Hourly Peach ET v Wind
June 29-30, 1994
wind Lysimeter ET
June 29 ET 0.30 inches
June 30 ET 0.28 inches
-
0.20
0.40
0.60
0.80
1.00
1.20
10
0
30
0
50
0
70
0
90
0
11
00
1300
15
00
17
00
19
00
21
00
23
00
10
0
30
0
50
0
70
0
900
11
00
13
00
15
00
17
00
19
00
21
00
23
00
No
rmali
zed
Valu
es
Hour of Day
Hourly Peach ET inches
June 29-30, 1994
ETo Lysimeter ET
June 29 ET 0.30 inches
June 30 ET 0.28 inches
Vapor Pressure Deficit
High leaf area index
Open canopy with good air circulation
Characteristics of peach trees
A lot of sunshine
Warm Temperatures
Arid Region
Vapor Pressure Deficit
-
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
100 400 700 1000 1300 1600 1900 2200 100 400 700 1000 1300 1600 1900 2200
Vap
or
Pre
ssu
re (
kP
a)
Hour of Day
Hourly Vapor Pressure June 29-30, 1994
Vapor Pressure Saturation Vapor Pressure
June 29 ET 0.30 inches
June 30 ET 0.28 inches
Calculation Procedures
Vapor calculated from humidity and temperature
Vapor Pressure Deficit = Vapor Pressure(average) minus
the Saturated Vapor Pressure(average)
Where
Vapor Pressure (average) is the average of the hourly
vapor pressures
Saturated Vapor Pressure is the Average of the
Saturation Vapor Pressure for the Minimum and
Maximum Temperatures
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
3/1/1994 4/1/1994 5/1/1994 6/1/1994 7/1/1994 8/1/1994 9/1/1994 10/1/1994
Inch
es
Date
Daily Peach Tree ET v ETo
1994 UC Kearney Agriculture Center in Parlier California
ET ETo
y = -2E-07x3 + 4E-05x2 + 0.0053x + 0.124
R² = 0.8491
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
60
66
72
78
84
90
96
10
2
10
8
11
4
12
0
12
6
13
2
13
8
14
4
15
0
15
6
16
2
16
8
17
4
18
0
18
6
19
2
19
8
20
4
21
0
21
6
22
2
22
8
23
4
24
0
24
6
25
2
25
8
26
4
27
0
27
6
28
2
28
8
29
4
30
0
Kc
Day of Year
Daily Peach ETo Crop Coefficient
1994 UC Kearney Agriculture Center in Parlier California
0
0.2
0.4
0.6
0.8
1
1.2
3/1/1994 4/1/1994 5/1/1994 6/1/1994 7/1/1994 8/1/1994 9/1/1994 10/1/1994
No
rmali
zed
(M
ax
. valu
e =
1)
Date
Daily Peach Tree ET v. Vapor Pressure Deficit1994 UC Kearney Agriculture Center in Parlier California
ET Vapor Pressure Deficit
y = 0.1128x
R² = 0.8538
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
- 0.50 1.00 1.50 2.00 2.50 3.00 3.50
ET
(in
ches
)
Vapor Pressure Deficit (kPa)
Daily Peach Tree ET v. Average Vapor Pressure Deficit
1994 UC Kearney Agriculture Center in Parlier California
Result of Cumulative ET using a Single
Coefficient to Estimate ET
0
5
10
15
20
25
30
35
40
3/1/1994 4/1/1994 5/1/1994 6/1/1994 7/1/1994 8/1/1994 9/1/1994 10/1/1994
Cu
mu
lati
ve
ET
(in
ches
)
Date
ET from Lysimeter ET from Vapor Pressure Deficit
Cumulative Daily Peach Tree ET v. ET from Vapor Pressure Deficit
1994 UC Kearney Agriculture Center in Parlier California
ET = 0.1128 *VPD
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
3/
1
3/
8
3/
15
3/
22
3/
29
4/
5
4/
12
4/
19
4/
26
5/
3
5/
10
5/
17
5/
24
5/
31
6/
7
6/
14
6/
21
6/
28
7/
5
7/
12
7/
19
7/
26
8/
2
8/
9
8/
16
8/
23
8/
30
9/
6
9/
13
9/
20
9/
27
10
/4
10
/1
1
10
/1
8
10
/2
5
Inch
es
Date
Daily Peach Tree ET v ETo
2003 UC Kearney Agriculture Center in Parlier California
ET ETo
y = -3E-05x2 + 2.1834x - 41353
R² = 0.9229
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
3/
1
3/
8
3/
15
3/
22
3/
29
4/
5
4/
12
4/
19
4/
26
5/
3
5/
10
5/
17
5/
24
5/
31
6/
7
6/
14
6/
21
6/
28
7/
5
7/
12
7/
19
7/
26
8/
2
8/
9
8/
16
8/
23
8/
30
9/
6
9/
13
9/
20
9/
27
10
/4
10
/1
1
10
/1
8
10
/2
5
Kc
Date
Daily Peach ETo Crop Coefficient
2003 UC Kearney Agriculture Center in Parlier California
Kc Poly. (Kc)
y = 0.1185x
R² = 0.852
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
- 0.50 1.00 1.50 2.00 2.50 3.00 3.50
ET
(in
ches
)
Vapor Pressure Deficit (kPa)
Daily Peach Tree ET v. Average Vapor Pressure Deficit
2003 UC Kearney Agriculture Center in Parlier California
0
0.2
0.4
0.6
0.8
1
1.2
3/1 3/83/153/223/294/54/124/194/265/35/105/175/245/316/76/146/216/287/57/127/197/268/2 8/98/168/238/309/69/139/209/2710/410/1110/1810/25
No
rmali
zed
(M
ax
. valu
e =
1)
Date
Daily Peach Tree ET v. Vapor Pressure Deficit2003 UC Kearney Agriculture Center in Parlier California
ET Vapor Pressure Deficit
0
5
10
15
20
25
30
35
40
45
3/
1
3/
8
3/
15
3/
22
3/
29
4/
5
4/
12
4/
19
4/
26
5/
3
5/
10
5/
17
5/
24
5/
31
6/
7
6/
14
6/
21
6/
28
7/
5
7/
12
7/
19
7/
26
8/
2
8/
9
8/
16
8/
23
8/
30
9/
6
9/
13
9/
20
9/
27
10
/4
10
/1
1
10
/1
8
10
/2
5
Cu
mu
lati
ve
ET
(in
ches
)
Date
ET Vapor Pressure Deficit
Cumulative Daily Peach Tree ET v. ET from Vapor Pressure Deficit
2003 UC Kearney Agriculture Center in Parlier California
y = -3E-05x2 + 0.0144x - 0.6644
R² = 0.7432
-
0.20
0.40
0.60
0.80
1.00
1.20
1.40
1.60
1.80
0 50 100 150 200 250 300 350
Kc
for
ET
o (
ET
/E
To
)
Julian Day
Daily Peach Tree Kc for (ET/ETo) v Julian Date
1988 - 2004 UC Kearney Agriculture Center in Parlier California
y = 0.1184x
R² = 0.7192
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
- 0.50 1.00 1.50 2.00 2.50 3.00 3.50
ET
(mm
)
Vapor Pressure Deficit (kPa)
Daily Peach Tree ET v. Average Vapor Pressure Deficit
1991-1995 and 2001-2004 UC Kearney Agriculture Center in Parlier California
Spanish Fork Weather Data (2014)
0
0.5
1
1.5
2
2.5
3
3.5
4
Vap
or
Pre
ssu
re D
efic
it (
kP
a)
Vapor Pressure Deficit
2014 Spanish Fork, Utah
Lower vapor pressure deficit in August than normal
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
Inch
es/
day
Daily ETo and ET from Vapor Pressure Deficit
Spanish Fork, Utah weather Data 2014
ET from VPD ETo
0
5
10
15
20
25
30
35
Cu
mu
lati
ve
Inch
esET from Kc v. ET from PDV(California Calibration)
Spanish Fork, Utah weather Data 2014
ET from VPD ET from Kc
Thoughts and Observations
Average vapor pressure deficit are slightly higher in
Utah County than the Central Valley (Will review
more historical climate data)
Due to higher elevation and greater day-night
temperature differences.
Use the high vapor pressure deficit data from
California to see if ET has a maximum (stomata
closure).
Using Vapor Pressure Deficit is less calculation than
Penman equations and only a single coefficient is
needed.
Fruit Production
Fruit Production
Best Strategy is to have an irrigation system with good
uniformities and flexibility.
Consider micro-irrigation
Many high value are harvested during a high water use
period, so don’t sacrifice quality base
Maintain adequate soil moisture.
0
5
10
15
20
25
30
0 10 20 30 40 50 60 70 80 90 100
Irri
gati
on
Dep
th (
in)
Area Receiving less than Indicated Depth (%)
Irrigation Depth Distribution
50 % of Area Fully Irrigated
CU=70% CU=80%" CU=90%
Area of deep
percolationAssumes ET from Irrigation of 15 inches
0
5
10
15
20
25
30
35
40
45
0 10 20 30 40 50 60 70 80 90 100
Irri
gati
on
Dep
th (
in)
Area Receiving less than Indicated Depth (%)
Irrigation Depth Distribution
75 % of Area Fully Irrigated
CU=80%" CU=90% CU=70%
Area of deep
percolation
Typical irrigation recommendation for a full water supply (75% of area fully irrigated)
0
5
10
15
20
25
0 10 20 30 40 50 60 70 80 90 100
Irri
gati
on
Dep
th (
in)
Area Receiving less than Indicated Depth (%)
Irrigation Depth Distribution
25 % of Area Fully Irrigated
CU=70% CU=80%" CU=90%
Area of deep percolation
Questions