The Interaction of Aeolian Sand and Slope on Runoff and Soil Loss on a Loess Slope via Simulated Rainfall under Laboratory Conditions

Abstract

The wind–water erosion crisscross region, where the topography is complicated, is the most severe area of soil erosion on the Loess Plateau. The wind and terrain both have an impact on the soil water erosion process. In order to evaluate the effects of sand cover on runoff and soil loss characteristics, a series of experiments was conducted in two contrasting treatments. One treatment was a bare loess soil slope serving as the control, and the others were sand-covered loess slopes with five different slopes. The results showed that the runoff time, total runoff yield, and total soil loss were different between the sand-covered slope and the loess slope on the slope of 15°. The sediment concentration of the sand-covered slope was significantly higher than that of the loess slope during the entire rainfall process (p < 0.05). The increase in the slope gradient shortened the surface runoff initiation times and enhanced the total runoff volume and soil loss. The total runoff volume and the total soil loss were 39.7 L and 44.3 kg, respectively, on the sand-covered slope of 10°. When the slope gradient increased from 10° to 30°, the total runoff volume and the total soil loss increased by 22.8 L and 42.8 kg, respectively, while the surface runoff initiation times shortened by 300 s. For the sand-covered slopes, the erosion processes appeared to be mainly dominated by sediment transport. The correlation between soil loss rates and slope gradients demonstrated the secondary polynomial function. In addition, the critical slope of sand-covered slopes was from approximately 23° to 28°. The proportion of sand cover and slope responsible for soil erosion was 3:1, which means the wind effect was more important than the terrace factor in terms of soil water erosion in the wind–water erosion crisscross region. The results provide a theoretical basis for soil erosion control in this area.

Variation Characteristics of Two Erosion Forces and Their Potential Risk Assessment in the Pisha Sandstone Area

“…Soil erosion is related to external erosion forces, but the response of external forces differs due to underlying surface conditions In the present study, the two external erosion forces showed obvious spatial differentiation, as shown in Figure 6, which implies that the spatial distribution of the related erosion will be different in this area. Soil erosion is related to external erosion forces, but the response of external forces differs due to underlying surface conditions such as topography, land use, and soil [36,37]. To facilitate further erosion studies in the area, we overlaid the results of the grading of the external forces with the slope of the area (Figure 9a).…”

Collapsibility Mechanisms and Water Diffusion Morphologies of Loess in Weibei Area

“…Flow boundary conditions can be set as flow boundaries or hydraulic head boundaries with time as a variable in SEEP/W. Longterm application practices [30][31][32][33] have proven the reliability of SEEP/W in analyzing saturated-unsaturated seepage problems and demonstrated the feasibility of using it for two-dimensional saturated-unsaturated seepage analysis.…”

Study on Aeolian Sand-Box Backfill Geomechanical Characteristics and Overlying Strata Control Effects

“…The conclusion highlighted the formation of dense needle-like calcium carbonate after carbonization and curing as the fundamental reason for increased bearing strength. Arias-Trujillo et al [23][24][25][26] explored the mechanical properties of laterally constrained aeolian sand, finding that increased lateral constraint strength enhances load-bearing performance and provides stronger restraint against soil displacement.…”