## Materials and Methods
### Rainfall Parameters  
At all sites, rainfall data were collected with a rain gauge (tipping bucket or balance principle). To obtain the \(KE\) of rainfall, each site was equipped with an optical laser disdrometer, which measures raindrop size and velocity distribution in one-minute intervals. The PWS100 Present Weather Sensors from Campbell Scientific (PWS100) were installed in Mistelbach and Petzenkirchen, and the Laser Precipitation Monitor from Thies Clima (Thies) in Prague. The devices differ in measurement principle, sampling area, and drop size and velocity distribution classes. The PWS100 sampling area was 40 cm\({}^{2}\), in which the drops are categorized in 34 size and 34 velocity classes. The Thies had a sampling area of 44.1 cm\({}^{2}\), with 22 drop sizes and 20 velocity classes. Both disdrometer types differentiate raindrops from hail, ice pellets, and graupel. A detailed description of the disdrometer and rainfall monitoring set-ups at the three sites is given in [PERSON] et al. [57]. The rainfall kinetic energy per area, \(KE\) (J m\({}^{-2}\)), was calculated for the diameter class \(i\) and velocity class \(j\) that are provided by the disdrometer, as follows:  
\[KE\ =\ \sum N_{i,j}\frac{1}{12.A}\cdot\pi\cdot 10^{-6}\cdot p\cdot D_{i}^{3} \cdot v_{j}^{2}, \tag{1}\]  
where \(N_{i,j}\) is number of detected raindrops of a certain size class \(i\) and velocity class \(j\); \(A\) is the sampling area of the disdrometer (m\({}^{2}\)); \(\rho\) is density of water (g cm\({}^{-3}\)); \(D_{i}\) is mean drop diameter (mm) of size class \(i\); and \(v_{j}\) is mean fall velocity (m s\({}^{-1}\)) of velocity class \(j\). The mass of the raindrop is calculated assuming a spherical drop shape. Total \(KE\) is the sum of kinetic energies for each drop size and velocity, multiplied by the number of drops in the corresponding classes. Cumulative \(KE\) of a single rainfall event, \(KE_{sum}\) (J m\({}^{-2}\)), was defined as  
\[KE_{sum}\ =\ \sum_{i,j=1}^{n}KE_{i}, \tag{2}\]  
Figure 2: Experimental set-up for splash erosion measurements: (**a**) splash cup with mesh at the bottom; (**b**) splash cup filled with soil; (**c**) splash collector; and (**d**) connection with drainage pipe to water and soil collector. where \(KE_{i}\) represents the \(i\)-th minute of the rainfall event. The \(KE\) per rainfall duration was calculated as  
\[KE_{h}\ =\ \frac{KE_{sum}}{T} \tag{3}\]  
where the \(KE_{h}\) is kinetic energy per hour (J m\({}^{-2}\) h\({}^{-1}\)) and \(T\) is total duration of a rainfall event (h), measured from the beginning of rainfall. The results obtained in the recent study by [PERSON] et al. [57] showed that the differences in rainfall measurements from different disdrometer types, including PWS100 and Thies, influenced the interpretation of rainfall \(KE\). That study concluded that the Thies disdrometer measured higher numbers of smaller drops; therefore, it underestimated the rainfall \(KE\). To ensure comparable results obtained from the two disdrometer types used in this study, we applied the suggested correction factor by [PERSON] et al. [57] for the Thies disdrometer. The correction is the ratio of the slope factors obtained from the \(KE\) and the intensity relationships for the PWS100 and Thies disdrometers. Accordingly, the final \(KE\) for the Thies disdrometer is calculated as in Equation (2) and multiplied with a correction factor of 1.36. For the periods when the disdrometer data were not available due to disruptions or errors, the \(KE\) was calculated based on \(KE\) and intensity relationships developed for the three sites, according to the data investigated in [PERSON] et al. [40]. The \(KE\) is presented as the function of the intensity, which was available from the rain gauge. The average rainfall intensity \(I_{av}\) (mm h\({}^{-1}\)) of single rainfall event considered the amount of rainfall over a time period, and is expressed as  
\[I_{av}\ =\ \frac{P}{T}, \tag{4}\]  
where \(P\) is the cumulative rainfall precipitation (mm) over rainfall duration \(T\) (h).