Changeability of runoff and soil loss from inclined mid-sized plots under simulated upward wind-driven rain

Abstract

The present study investigated the interaction of wind and rain (WDR) on splash and interril erosions under laboratory conditions. The corresponding experiments were carried out with rainfall intensity of 50 mm h−1 with a duration of 30 min under no-wind control conditions and two wind velocities viz., 3 and 6 m s−1 at a slope of 12%. The study was conducted on sandy-loam soil from summer rangelands of the Northern Alborz Mountain in Iran. The soil collected was transported to the Rainfall and Erosion Simulation Laboratory. The prepared 6 × 1 m-plots were concurrent with the simulation of the WDR. Moreover, three splash cups were used to measure splash erosion, and each cup was placed on the soil surface at distances of 1.5, 3.0, and 4.5 m from the plot outlet. The results displayed the significant effects of wind (P < 0.01) on runoff generation and soil erosion components. Therefore, the mean runoff and runoff coefficient decreased while increasing wind velocity increased sediment concentration and soil loss. The mean runoff volume and coefficient were 103.48, 94.62, and 88.82 L and 94.43, 87.23, and 81.62 % at wind velocities of 0, 3, and 6 m s−1, respectively. In addition, the mean soil loss and sediment concentration were 414.94, 1057.47, and 1375.48 g; and 31.35, 156.31, and 303.75 g L−1; at 0, 3, and 6 m s−1 wind velocities, respectively. Besides, the mean net splash increased significantly with increasing wind velocity, from 9.58, 14.93, and 18.63 g, respectively, as wind velocity changed from 0 to 3 and then 6 m s−1. It has been proven that WDR soil erosion was higher than no-wind rain. This research could increase soil managers' awareness of solution strategies.