Comparison of Guelph permeameter and Tension Disc Infiltrometer Methods for Measurement Soil Saturated Hydraulic Conductivity

In this study two methods of measuring saturated hydraulic conductivity namely: Guelph permeameter and Tension Disc Infiltrometer were compared in the experimental field of Moghan Faculty of Agriculture containing Sandy-loam soil texture . Guelph experiments were performed by using Guelph penetrometer model k2800. In this regard, 15 boreholes each with 5 cm diameter and 25 cm depth were drilled in a grid of 2×2 m and discharge was measured at the hydraulic heads of 5 and 10 cm. .. Experiments were performed based on completely randomized design with 4 treatments and 15 replicates. Also in the Tension Disc Infiltrometer, determination of saturated hydraulic conductivity was performed on the same grid with 5, 10, 15 cm suction heads. The average hydraulic conductivity obtained for Tension Disc Infiltrometer, Guelph permeameter in 5,10 cm of hydraulic heads and Guelph two depths analysis was found to be 7, 3, 4, 6.2 cm per hour, respectively. Results of Fisher test revealed that all methods are classified in a group and not significantly different from each other at the 0.01 level and beyond, . Average values for the inverse of macroscopic capillary length parameter was obtained to be 0.07 cm-1 and as the value of saturated soil hydraulic conductivity increased , an increase in the value of inverse macroscopic capillary length parameter was observed.