The Determination of wetting depth of soil in irrigation

Knowing wetting depth of soil is an important factor to determine the irrigation water amount depends on the development of plant root system in vegetation period. In this study, wetting depth of soil in corn grown area was estimated according to active soil layer, irrigation water amount, soil moisture change and field capacity using mathematical approach. In 40, 50, 60, 70, 80 and 90 cm soil layers, “wetting coefficients” and wetting depths for irrigation water amount of 900 m3 ha-1 were determined as 1.62, 1.43, 1.26, 1.13, 1.02, and 109, 116, 109, 95, 84 cm, respectively. In the same soil layers, “wetting coefficients” and wetting depths for irrigation water amount of 950 m3 ha-1 were determined as 1.71, 1.51, 1.33, 1.19, 1.07 and 119, 128, 122, 106, 94 cm, respectively. As a result, it was determined that basic factors effecting on wetting depth in irrigation were irrigation water amount and depth of active root zone