The soil erosion experiment was conducted using simulated
rainfall equipment with 9.5 m in height (drop diameter is 2.5 mm
and terminal velocity is 8.5 m s−1), and all processes followed the
ASTM-D7101 standard (America Standard Testing Materials, ASTM).
Soil erosion processes are widely performed in the field and laboratory
using rainfall simulators and these simulations play an important
role in controlling repeatable conditions and adjusting the required
rainfall intensity (Tejada and Gonzalez, 2007). The erosion experiment
simulated a rainfall intensity of 80 mm h−1 and a 10% slope
gradient because this is the average slope gradient in the field.