Measurement of Field-Saturated Hydraulic Conductivity by Using Guelph and Velocity Permeameters

摘要

Field experiments were conducted to evaluate the performance of two recently developed in situ techniques to measure saturated hydraulic conductivity (K). These two techniques are (1) the constant-head well permeameter method using the Guelph permeameter, and (2) the falling-head permeameter method using the velocity permeameter. K was measured on a silt loam soil at eight sites and for four different depths (150, 300, 450, 600 mm) at each site by using these two techniques. K determinations were also made in the laboratory by using a constant-head permeameter on undisturbed soil columns collected from all test sites and depths. Measurements of K for the selected test sites and conditions indicate that Guelph and velocity permeameters provided reasonably similar values. Both methods are simple to use and easily portable, and both produce results in a relatively short time (usually 15 min to 20 min for the velocity permeameter and 60 min to 90 min for the Guelph permeameter for a single measurement). Field-measured K values tended to be much lower than laboratory values.