ELECTRICAL TECHNIQUE FOR MONITORING WETTING PATTERN UNDER TRICKLE SOURCE

Knowledge of the wetted pattern dimensions is important in designing and managing efficient drip irrigation systems. Distance between emitters, root zone depth and emitter flow rates must be matched to the soil’s wetting characteristics and the amount and timing of water to be supplied to meet the crop needs. To estimate the wetted pattern dimensions correctly during laboratory experiments in soil section, the wetting front progress should be allowed to move freely into the soil profile in all directions. The developed technique depending on number of electric circuits distributed on steel axes (electrical measurement axes) inside a wooden rectangular soil box was used to determine the wetting front movement. This technique of determining wetted pattern dimension, avoids the side effects of the Plexiglass wall, in conventional technique, on the soil moisture movement. As a result, the obtained wetted pattern agrees closely to that described by Zur (1999) and Ismail et. al (2006).