Estimating of wetted soil volume dimensions in the surface drip irrigation on textured medium soil: dry initial soil condition

The use of models to describe or estimate the water distribution in the wetted soil volume can be an important alternative in the definition of the irrigation management and design. The objective of this work was to estimate dimension data of soil wetted volume generated in different soil types under surface drip irrigation using mathematical models of the literature. There were selected data from one class of soil (loam soil), simulating three emitter flow rates (0.503, 1.48 and 2.70 L h-1) and 12 soil water application times (1 to 12 h) with a dry initial soil condition. The values of the wetting pattern were estimated (maximum width and maximum depth) by the five studied models (one numerical, one analytical and three empirical). The simulated maximum width ranged from 18.67 to 108.89 cm and maximum depth ranged from 5.98 to 61.75 cm. The numerical (PSIGS) and analytical (WetUp) models present more reliable results. The empirical model DIPAC presents results with values and behavior similar to those of more robust models