Comparative Analysis of Splash Erosion Devices for Rainfall Simulation Experiments: A Laboratory Study

Abstract

For the study of soil erosion it is important to set up the experiments well. In the experimental design one of the key factors is the choice of the measurement device. This is especially important when one part of the erosion process needs to be isolated, such as for splash erosion. Therefore, the main aim of this research is to list the general characteristics of the commonly used splash erosion devices and to discuss the performance, to be able to relate them, and make suggestions regarding their use. The devices we selected for this comparative comparison were: the splash cup, funnel, Morgan tray, Tübingen cup, tower, and the gutter. The devices were tested under the same conditions (rainfall characteristics, slope, and soil type) to assess their hydrological response under different intensities of simulated rainfall. All devices were installed on a sloping plot (10°) with sandy soil, and were exposed to 10 min. of simulated rain with intensities ranging from 60 to 172 mm/h to measure the splashed sediment, and to describe problems and differences among them. The results showed that the Tübingen cup was the best performing device to measure kinetic energy of the rain, but, because of its design, it is not possible to measure the detached splashed sediment under natural (field) conditions. On the other hand, the funnel device showed a significant relation with rain intensity because it loses little sediment to washing. In addition, the device is easy to use and cheap. Therefore, this device is highly recommended to estimated splash erosion. to the good performance measuring the actual splash erosion, because it loses little sediment by washing. The device is also cheap and easy to install and manage.

Experimental Setup for Splash Erosion Monitoring—Study of Silty Loam Splash Characteristics

“…The overall relationship between the mass of the eroded particles and the rainfall kinetic energy has a linear trend ( Figure 5). The coefficient of determination is 0.7 which is higher than or in a similar range as presented in comparable studies (e.g., [6,15,41]). Table 1 summarizes selected splash erosion experiments from the literature to show how the experiments vary in setup.…”

“…They show similar, most often linear, relationships between the amount of detached soil particles and various rainfall characteristics. The slope of the linear trendline differs in each study because of differing experimental setups (rainfall duration, sample preparation) and soil properties [6,15,42]. Bisal [17] and Mazurak and Mosher [18] already experimentally showed that the splashed amount is linearly dependent on drop size and velocity.…”

“…The results may change if different types of the rainfall simulators (with various drop size distribution or drop velocities) are applied. Fernández-Raga et al [15] demonstrated that splash erosion estimation is strongly dependent on the splash collection setup. Poesen and Torri [3] found that the area of the splash cup is the main influencer defining the amount splashed and therefore coefficients for different splash cup areas should be used.…”

“…The most common problem with splash erosion experiments is that it is difficult to compare results across studies due to each author's differing experimental setup [15]. Many different splash cup setups with various sizes and trapping principles have been used to measure splash erosion.…”

The Effect of Hydrology on Soil Erosion

“…To understand soil erosion processes, each pedological, climate, geomorphological and hydrological parameter must be assessed. In Fernández-Raga et al [10], the authors highlighted the need to choose the most correct measurement device during the experimental design; for example, in the case of splash erosion. They evaluated the hydrological response under different intensities of simulated rainfall of different devices under the same conditions.…”