Abstract
Spatial and temporal variability of soil water extraction from the root zone affect soil water balance determination. The number of sensors installed in the root zone in studies addressing water balance is still set arbitrarily. This study provided an investigation of the water extraction process by banana (Musa spp.) roots by (i) determining the variability of water extraction from the banana tree root zone, (ii) detecting differences in the estimation of evapotranspiration (ET) by the soil water balance method when the number of soil profiles monitored in the roots zone varies, (iii) and; determining the minimum number of Time Domain Reflectometry (TDR) probes needed to obtain ET precision and accuracy similar to that determined by a drainage lysimeter. The field experiment was conducted in Cruz das Almas, in the state of Bahia, Brazil, where a drainage lysimeter was installed on a banana plantation. The water extraction in the banana root zone was quantified by the water content variations monitored in 72 points by TDRs, with measurements at 15-min intervals. The variability of water extraction in the banana root zone was medium to high. The range of variability affects the reliability of the crop evapotranspiration calculation by the soil water balance method. To prevent an overestimation of banana evapotranspiration, the water extraction in the soil profile must be monitored with at least 16 TDR probes installed at a minimum distance of 0.9 m and a minimum depth of 0.7 m.
Highlights
Information on crop water requirements is the main reference for efficient irrigation
This study provided an investigation of the water extraction process by banana (Musa spp.) roots by (i) determining the variability of water extraction from the banana tree root zone, (ii) detecting differences in the estimation of evapotranspiration (ET) by the soil water balance method when the number of soil profiles monitored in the roots zone varies, (iii) and; determining the minimum number of Time Domain Reflectometry (TDR) probes needed to obtain ET precision and accuracy similar to that determined by a drainage lysimeter
Regardless of the soil water balance method, changes in water content are commonly monitored at key points in the soil volumes, using sensors such as tensiometers, time domain reflectometry (TDR) probes, frequency domain reflectometry (FDR) probes or neutron probes (Green and Clothier, 1995; Andreu et al, 1997; Palomo et al, 2002)
Summary
Information on crop water requirements is the main reference for efficient irrigation. Several methods have been used to determine water consumption of banana, such as micrometeorological (Santos et al, 2009; Ding et al, 2013), lysimetric (Santana et al, 1993) and soil water balance. For both drainage lysimeters and soil water balance methods, ET is calculated by directly measuring the components of the soil water balance applied over a period of time (Δt) within the soil volume. Regardless of the soil water balance method, changes in water content are commonly monitored at key points in the soil volumes, using sensors such as tensiometers, time domain reflectometry (TDR) probes, frequency domain reflectometry (FDR) probes or neutron probes (Green and Clothier, 1995; Andreu et al, 1997; Palomo et al, 2002)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
