Effects of tillage microrelief units on splash erosion: A case study from the Loess Plateau, in China

A tillage microrelief unit is the smallest spatially discontinuous area unit of tillage microrelief. Understanding the impact of tillage microrelief units on splash erosion is essential for selecting suitable tillage measures and employing soil and water conservation practices. The objective of this study was to investigate the characteristics and mechanisms of splash erosion under different tillage microrelief units in various directions and distances using the rainfall simulation experiment in the soil landscape of the Loess Plateau region in China, characterized primarily by sloping farmland as the main land use type. Three typical microrelief units, namely, artificial digging (AD), contour tillage (CT), and straight slope conditions (SSC) were designed at 0°, 3°, 5°, 10°, 15°, and 20° slopes. Tillage microrelief units with high surface roughness produced more splash erosion than flat lands. Further, the highest surface roughness increased the total splash amount by 102% relative to flat lands. The tillage microrelief unit itself was elevated with a certain slope, which increased the downslope splash of CT, SSC, and AD by 121%, 173%, and 11%, respectively. Different surface roughness values and slopes under different microrelief units were used to determine the amount of splash erosion. The results showed that the total splash amount responded significantly (P