John A. Moody Brian A. Ebel 2013 <p>Wildfires frequently result in natural hazards such as flash floods (Yates <i>et al</i>., 2001) and debris flows (Cannon <i>et a</i>l., 2001a,b; Gabet and Sternberg, 2008). One of the principal causes of the increased risk of post-wildfire hydrologically driven hazards is reduced in filtration rates (e.g. Scott and van Wyk, 1990; Cerdà, 1998; Robichaud, 2000; Martin and Moody, 2001). Beyond the reduction in peak infiltration rate, there is mounting evidence that the fundamental physics of infiltration in wild fire-affected soils is different from unburned soils (e.g. Imeson <i>et al.</i>, 1992; Moody <i>et al.</i>, 2009; Moody and Ebel, 2012).</p><p>Understanding post-wildfire hydrology is critical given the increasing wildfire incidence in the western USA (Westerling <i>et al.</i>, 2006) and elsewhere in the world (Kasischke and Turetsky, 2006; Holz and Veblen, 2011; Pausas and Fernández-Muñoz, 2012). Wildfire is a disturbance event with global distribution (Bowman <i>et al.</i>, 2009; Krawchuk <i>et al.</i>, 2009; Pechony and Shindell, 2010; Moritz<i> et al.</i>, 2012), and with increasing populations moving into fire-prone areas, understanding post-wildfire infiltration is of increasing importance for predicting post-wildfire consequences. Runoff is generally controlled by the infiltration-excess mechanism in fire-affected soils (e.g. Mayor <i>et al</i>., 2007; Onda <i>et al.</i>, 2008; Kinner and Moody, 2010). It is essential that the fire community have conceptual models, physical equations and tools (i.e. numerical models) to predict infiltration and thus excess rainfall (after Horton, 1933), which can provide estimates of peak discharge, start of runoff, time to peak and total runoff for hydroclimatic scenarios after wildfires. Reductions in saturated hydraulic conductivity&nbsp;<i>K</i>_sat [LT^-1] are common for fire-affected soils, and the relatively low values observed explain the elevated flash flood hazards (e.g.&nbsp;<i>K</i>_sat of 1–100 mm h^-1 , Robichaud, 2000; Yates <i>et al.</i>, 2000; Martin and Moody, 2001; Robichaud <i>et al.</i>, 2007; Moody <i>et al.</i>, 2009; Neary, 2011; Nyman <i>et al.</i>, 2011).</p> application/pdf 10.1002/hyp.9696 en Wiley Rethinking infiltration in wildfire-affected soils article