Water drop erosivity: Effects on soil splash

Detachment and transport of soil particles by water drop impact can be analysed in terms of the kinetic energy (1/2 MV2), or momentum (MV) of the water drop. Therefore density, diameter, fall height, velocity of the water drop and area of impact need to be considered. The drop impact pressure, which is the mathematical combination of these characteristics, has been interacted with soil splash characteristics such as the amount, the mass distance distribution and the mean distance. A splash board divided into 13 concentric compartments to collect the splashed particles and different capillaries produced drops with diameters between 3.7mm and 5.8mm formed the basis of the laboratory work. The results shown that the involvement of the drop diameter steepened the curves representing the relationship between soil splash and drop pressure, which means that the drop diameter has an effect on soil splash. But, according to the correlation analysis, the involvement of the diameter did not improve the coefficient of determination of the relation between drop pressure and soil detachment except for the exponential function. In addition, the relationships between drop pressure and soil splash characteristics are mostly presented by a power functions.