Intensity and persistence of water repellency at different soil moisture contents and depths after a forest wildfire

Abstract The Mediterranean mixed coniferous and broad-leaved forest of Moarda (Palermo) was affected by a large wildfire in summer 2020. In spring 2021, burned unburned loam soil sites were sampled the water drop penetration time (WDPT) ethanol percentage (EP) tests applied to assess influence wetting-drying processes content on post-fire repellency (SWR) as well its vertical distribution. According WDPT test, surface layer natural soils severely hydrophobic at intermediate contents roughly corresponding wilting point SWR reduced either for very dry conditions (air- or oven-dried conditions) wetter close field capacity. For these soils, EP test yielded results agreement with WDPT. An wetting/drying cycle detected as, given content, generally higher drying than wetting process. always wettable independently content. distribution modified maximum hydrophobicity layer, that located moved depth 2–4 cm sites. confirmed can induce destruction naturally occurring create shallow may increase overland flow erosion risk.