2012 ial conference a novel technique to measure the total evaporation and its components during...
TRANSCRIPT
![Page 1: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/1.jpg)
2012 IAL Conference
A novel technique to measure the total evaporation and its components during
sprinkler irrigation
Jasim Uddin
Rod Smith
Nigel Hancock
Joseph Foley
National Centre for Engineering In Agriculture (NCEA)
University of Southern Queensland,
Toowoomba QLD 4350
Australia
![Page 2: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/2.jpg)
Presentation layout
Background Hypothesis Objectives Methodology Results Conclusions
![Page 3: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/3.jpg)
BackgroundFigure 1: Components of evaporation losses during sprinkler
irrigation
Droplet evaporation
Canopy evaporation
Soil evaporation
![Page 4: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/4.jpg)
Background
Components Theoretical Experimental
Canopy evaporation
8% Unable to measure
Droplet evaporation
<1% 0-45%
Soil evaporation negligible Unable to measure
![Page 5: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/5.jpg)
Limitations of the catch-can method
Laborious and time consuming Unable to measure ET over crop
(Source : Smith, Cotton CRC)
Catch-can
![Page 6: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/6.jpg)
Limitations of the lysimeter method
Figure 3: Measured ET using lysimeter and predicted ET (source : Thompson et al. 1997)
Lysimeter could not measure ET during irrigation
Irrigation period
![Page 7: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/7.jpg)
Background
Hypothesis:Eddy covariance – sap flow method can be used to measure total ET and its components during sprinkler irrigation
Objectives: To measure the total ET and transpiration
To estimate the components of ET
![Page 8: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/8.jpg)
Methodology
Figure 4: Experimental set up
Eddy covariance system
Sap flow system
![Page 9: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/9.jpg)
Methodology
Eddy covariance (ECV) system
Sonic anemometer
Infrared Gas analyzer
Net radiometer
![Page 10: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/10.jpg)
Sap flow system
Datalogger Hub
sensorInterface
![Page 11: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/11.jpg)
MethodologyMeasurements
Latent heat flux (λE) and sensible heat flux (H)
Eddy covariance technique Net radiation (Rn)
Four components net radiometer Soil heat flux (G)
Soil heat flux plates Transpiration (T) measured by
Sap flow method Air temperature (Ta) and Relative humidity (RH)
Temperature and RH probe
nE ET R H G
![Page 12: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/12.jpg)
Methodology
Data processing
Calculation of λE:
Bowen Ratio,
Calculations of ET in mm/hr :
Calculations of ETref : FAO Penman-Monteith
1nR G
E
/H E
(28.36 24)
EET
![Page 13: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/13.jpg)
Results
Figure 3: Measurement of ET and tarnspiration over mature cotton
![Page 14: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/14.jpg)
Results Figure 4: Components of total ET measured by ECV-sap flow
method
![Page 15: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/15.jpg)
Conclusions
Measurement of total ET during sprinkler irrigation is possible which includes:
canopy evaporation and droplet evaporation during
irrigation reduction of transpiration during irrigation canopy interception soil evaporation
![Page 16: 2012 IAL Conference A novel technique to measure the total evaporation and its components during sprinkler irrigation Jasim Uddin Rod Smith Nigel Hancock](https://reader030.vdocuments.us/reader030/viewer/2022032722/56649f445503460f94c659b1/html5/thumbnails/16.jpg)
Thanks for your attendance
Questions