Fire is a worldwide phenomenon that is expected to increase in severity and frequency by the Global warming. It has been estimated that more than 30% of the global land surface is subjected to a considerable frequency of vegetation fires (Chuvieco et al., 2008). Soils affected by fire may suffer physical, chemical and biological alterations. Fire can induce, enhance or destroy soil properties depending on factors such as temperature reached (DeBano et al., 1976; Certini, 2008), time of heating (Doerr et al., 2004), type of soil, quantity and type of fuel (Arcenegui et al., 2007) and pre-fire soil conditions. The persistence and the spatial distribution of fire effects on soils properties is a key factor controlling runoff dynamics, erosion, ash and sediment transport and water availability in burned soils. Nowadays, we still have to answer what do we have to do after a big fire? Then is crucial to understand what is happening in soils after a wildfire.