Confirming the suggestion of Loch (1984), Moss (1988) explained the importance of the rill flow transporting more effectively the sediments, with greater particles than those transported by sheet flow. The three modes can be very erosive, reducing the aggregates to primary particles. Summarizing part of his trials Moss (1988) discussed the three main mechanisms of water erosion: (1) airsplash that acts in the bare soil and is enhanced by the slope and wind, causing random displacements of particles, except for wind action or terrain slopes, or due to movements from spots of high activity to other ones with low activity, (2) overland water flow that can degenerate into rills and gullies, and (3) rainflow transport, that complements the splash effect. The erosive effect of the gravity drops can be even more intense when the wind moves the branches of the trees as Moss and Green (1987) detected in their experiment. In field observations, the craters formed by gravity drops falling the canopies sometimes detected by micro-fairy chimneys when a small stone or leaf protect the soil surface. Nevertheless, their experiments did not include real plants, except for a single, small branch of a tree. Moss and Green (1987) presented the potential effects of these drops falling from different layers of the plant canopy. The rain-flow transport of sediment increased as well with the gravity drops. The airsplash produced by the gravity drops were in some cases about half of the effect caused by raindrops reaching the ground at the terminal velocity. Therefore, a simple computation reveals that the kinetic energy of a gravity drop with a diameter of 5.3 mm falling from an elevation of 0.4 m is 2,770 times that of a mist drop of a diameter of 0.5 mm, and 0.973 times that of a drop of a diameter of 2.7 mm falling at terminal velocity on the ground. The geomorphological relevance of raindrop splash ranges on micro- to macrotopographic scale and influences source and sink dynamics concerning sediment transport and flow path development in the context of connectivity research and may be a landscape factor in ranges particularly in the case of wind-driven raindrops. Effects of raindrop splash are diffusion of surface material, supply with easily erodible sediments, compaction, and sealing, thus directly and indirectly affecting subsequent hillslope processes on various spatio-temporal scales. The extent of splash erosion is determined by drop-surface interactions with major influencing factors related to drop characteristics and soil surface properties. Splash erosion is the initial phase of soil erosion by rain and dominates particle erosion and redistribution prior to the generation of overland flow, and its impact on splash rates has not been fully understood yet. Raindrop splash describes processes related to a raindrop impacting a soil surface. Miriam Marzen, Thomas Iserloh, in Precipitation, 2021 Abstract
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