SOIL MOISTURE DISTRIBUTION UNDER MICRO IRRIGATION - Management, Performance, and Applications of Micro Irrigation Systems - page 136

ent system operating pressure were determined by collecting the volume of water in
the catch cans for a particular duration.
Wetting patterns in the soil were observed at different system operating pressures
(0.5 kg cm -2 , 1.0 kg cm -2 and 1.5 kg cm -2 ). The drip irrigation system was operated
continuously for one hour duration to supply water at 0.5, 1.0 and 1.5 kg.cm -2 op-
erating pressures without crop. Soil moisture content was estimated by gravimetric
method by collecting the soil samples in both horizontal (0, 15, 30 cm) and vertical
(0-15, 15-30, 30-45 and 45-60 cm) direction across the dripper (Fig. 1) after 1.0 h, 1
day, 3 day and 7 days after the operation of the system.

FIGURE 1 Locations of soil samples below the lateral line.

The soil samples were collected with the pipe auger to observe water movement in
the soil. The wetting front was recognized by the color difference of the wetted and
surrounding soils (Fig. 2). The horizontal and vertical wetting distances on the wetted
face were recorded by ordinary meter scale.