The potential effect of temperature on surface deformation after water drop impact in soils with different texture and moisture content

The splash phenomenon occurs when water drops hit the soil surface, making it the initial stage of most types of soil erosion caused by water. An effect of this phenomenon, in addition to the detachment and displacement of soil particles, is also the deformation of the soil surface. Climate change (including the occurrence of periods of very high temperatures) can affect the intensity of soil erosion processes. The aim of this work is to determine the influence of selected temperature conditions on soil surface deformation caused by the splash phenomenon at the initial stage of erosion. The goal was achieved by measuring the morphology of craters formed by the impact of a single drop. The research included the use of three soils varying in particle size distribution: loamy sand, sandy loam, and silty loam. Additionally, the work took into account two variants of initial soil moisture and three temperature conditions (including various temperatures of soil, air, and drop-forming water). The measurements were taken with a 3D scanner, determining depth, equivalent diameter, volume of the craters, and a dimensionless parameter α (depth-to-diameter ratio). Temperature effects were observed in silty loam, where craters became wider (from average diameter of 9.41 ± 0.31 to 10.47 ± 0.21 mm for pF = 1) but shallower (from average depth of 1.28 ± 0.05 to 1.00 ± 0.05 mm for pF = 1) with increasing temperature, and in loamy sand, where temperature influenced the differences in diameter and volume of craters formed between varying moisture conditions. The differences in crater morphology could be due to the influence of temperature on the viscosity and surface tension of water, which may have led to a change in susceptibility to deformation. The results provide an opportunity to better understand the evolution of erosion in the context of different thermal conditions and thus in some perspective on the impact of climate change.