TEMPORAL VARIATION OF THE MATRIC POTENTIAL OF A LATOSOL MONITORED BY TENSIOMETRY

Abstract

In order to obtain soil water availability data, monitoring with some devices is necessary, in which tensiometers are highlighted. However, there are factors that may cause errors in the readings of this equipment. Thus, the aim of this study was to monitor the water potential of a dystrophic Red Latosol with straw coverage at different times of the day, through tensiometers installed at different depths. The experiment was conducted in pots with a completely randomized design, with three repetitions in a 3x 3 x 2 factorial. Three times and three tensiometric cup installation depths, with and without straw soil coverage. Tensiometer evaluation time influenced soil water matric potential, and the highest soil water matric potential values were found in the uncovered soil. In the 12 p.m. evaluation time, the highest soil water matric potential mean values were observed, for both covered and uncovered soils. In addition, there was a 51.18% difference for 8 a.m. in the uncovered soil and a 30.10% difference in the soil covered by straw. Tensiometer installation depths influence soil water matric potential variation. The water soil matric potential values were observed at a depth of 0.15m. The highest soil water matric potential variation was observed in the uncovered soil at a depth of 0.15 m, except for 4 p.m., in which the highest variation was observed at the depth of 0.30 m. The variance tends to be higher at a depth of 0.15 m 12 p.m.