Characterizing the Evolution Of Fire Induced Hydrophobicity In the Post-Fire And Evaluation Of Ash and Char as Potential Sources of Hydrophobicity

Abstract

Managing fire-induced water-repellent soils in the aftermath of a severe fire can be troublesome and challenging. The water-repellent layer decreases the soil permeability and prevents moisture from entering the soil profile. In the post-fire environment uneven moisture distribution can hinder germination and revegetation. In addition, the decreased permeability caused by the water-repellent layer leads to increased runoff and soil erosion. Erosion robs the soil of its ability to support vegetation, and can lead to increased gully and rill formations, channel erosion, and slope failure. This study documents the evolution and explores the mechanisms of formation of soil water repellency created by the Lost Pines fire near Bastrop, TX. It also examines the potential role of ash and char created by the fire, in altering soil hydrology, and examines management implications.