Determination of Emitter Spacing Based on the Amount of Water Applied and Trickle Discharge Rates

摘要

This study was conducted with the objectives of determining effect of trickle discharge rates and amount of irrigation water applied on water distribution in the soil profile and to estimate the emitter spacing by the Wooding method and wetting front in the wetted soil volume in a clay soil. Total volume irrigation water of 16, 32 and 64 L were applied with discharge rates of 2, 4, 6 and 8 L/h and water has moved laterally to a distance of 45-60 cm from the trickle source 48 hrs after water application. Result of this study indicated that as the flow rates and amount of water applied increased, rate of moisture movement in the horizontal direction also increased. Experimental emitter spacing changed from 90 to 130 cm in the clay soil depending on the emitter discharge rates and volume of water applied. Using the same physical properties of soil, emitter spacing estimated by Wooding's equation varied from 44 to 93 cm. A second order relation was obtained between the emitter flow rates and emitter spacings when a total of 16 L water was applied.. When the amount of water applied was increased to 32 L, the relationship was linear.