Effects of hydrophobicity on splash erosion of model soil particles by a single water drop impact

Abstract

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Aerosol generation by raindrop impact on soil

“…In this work we consider droplets hitting dry soil, which is both wettable and firm enough to maintain its porous structure during the impingement. When droplets have an impact on powder surfaces or granular layers [40][41][42][43][44] , we did not observe bubble formation during the drop impingement. We speculate that if the porous media deform considerably during impact there are low permeability paths for air to escape from beneath the droplet and so it is not trapped.…”

Effects of fire on the physicochemical properties of soil in a slash-and-burn agriculture

“…While no changes occurred in this study, changes would be expected in cases where soil heating is more excessive, which would increase the complexity of the environmental processes occurring in this farming system. Among the principal effects of soil water repellency are changes in aggregate stability and enhancement of splash erosion of small particles (Ahn et al, 2013;Fox et al, 2007), a change in infiltration rate (Doerr et al, 2009), and a reduction in the topsoil strength, which can lead to rill initiation (DeBano, 2000).…”

Seasonal changes in the soil hydrological and erosive response depending on aspect, vegetation type and soil water repellency in different Mediterranean microenvironments

“…The higher S c in the transition season can be explained by the effect of SWR in soil surface. According to Ahn et al (2013), soil water repellency increases the distance of ejection of particles after a drop impact, which in hillslopes with a certain degree of inclination involves greater net downslope movement and, hence, net erosion of particles. Shakesby et al (2000) reported that in hydrophilic soils the wetting provoked an increase in the particles cohesion and, in consequence, a compact surface seal that limited the amount of splashed sediments was developed.…”