In situ determination of the water desorption characteristics of peat substrates

Abstract

This study shows that water desorption characteristics of peat substrates obtained using Tempe cells differ from those obtained using pots and a tension table apparatus. However, the latter method is time and resource consuming. An alternative method for routine and rapid determination of water desorption characteristics of undisturbed samples was tested. Measurements of water potential in pots were obtained using tensiometers. Volumetric water content was measured by time domain reflectometry (TDR). Water desorption characteristics were derived for three substrates in laboratory experiments and compared to water desorption characteristics obtained using a tension table. The approach using TDR and tensiometers appears to be reliable, fast and to allow large number of simultaneous water characteristic determinations. -from Authors