Influence of Initial Water Content on the Wettability of Autoclaved Soils

Abstract

Autoclaving is a commonly used practice to destroy microbial activity in soils but is thought to have a limited effect on other soil properties. Small changes in chemical composition have been reported, but there have been no previous reports of any alteration of physical properties. This study, however, showed that autoclaving can cause a major change in soil hydraulic properties. For samples with intermediate water contents (10–35% v/v), it caused severe or extreme water repellency in three of four soil types tested, although no effect for initially low or high water contents was found. These findings have important implications for any experimental work involving soil autoclaving as a pretreatment procedure but could also be used for generating otherwise similar samples differing only in terms of wettability.