Simulation of soil wetting pattern under point source trickle irrigation

Information on moisture distribution patterns under point source trickle emitters is a pre-requisite for the design and operation of trickle irrigation systems. This will ensure precise placement of water and fertilizer in the active root zone. The distribution pattern is influenced by the soil properties and the behavior of applied water. In this study, water movement in three soil types from a surface point source was investigated. Experimentation included determination of maximum depths and widths of wetted zone after one hour time interval of water application. The surface wetted radius increased with an increase in application rate. A good relationship was found between the surface wetted radius and the volume of water applied. This suggested that for a certain volume of water applied, a corresponding wetted surface radius can be predicted. The numerical values of wetted surface radius for each flow rate group were compared with those predicted by the suggested equations. Predictability of model was estimated as 96.8 and 95.3%, respectively, for prediction of wetted width and depth. The results showed good agreement for all application rates. © 2009 Asian Network for Scientific Information.