Can pore-clogging by ash explain post-fire runoff?

摘要: Ash plays an important role in controlling runoff and erosion processes after wildfire has frequently been hypothesised to clog soil pores reduce infiltration. Yet evidence for clogging is incomplete, as research focussed on identifying the presence of ash soil; actual flow remain unknown. We conducted laboratory infiltration experiments coupled with microscope observations pure sands, saturated hydraulic conductivity analysis, interaction energy calculations, test whether can (i.e. block such that hampered ponding occurs). Although results confirmed previous washing into pores, was not observed sands tested, nor were conditions found which this does occur. Clogging by means strong attachment sand deemed unlikely given negative surface charge two materials. Ponding due also considered improbable high ash–sand mixtures. This first mechanistic step towards analysing transport field soils therefore suggests pore occur sands. Discussion provided other mechanisms affect post-fire hydrology.