Erodibility of waste (Loess) soils from construction sites under water and wind erosional forces

Highlights: • Water and wind erosion simulations were used to study the erodibility of waste loess soils. • Waste subsoils were more erodible than waste topsoil under water erosion, but less erodible under wind erosion. • Soil erodibility factor (Ki) values are significantly correlated to ESP and slaking values under rainfall erosivity energy. • The susceptibility of soil to erosion by wind erosivity forces is controlled by dry aggregates characteristics. Excess soils from construction sites (waste soils) become a problem when exposed to soil erosion by water or wind. Understanding waste soil erodibility can contribute to its proper reuse for various surface applications. The general objective of the study was to provide a better understanding of the effects of soil properties on erodibility of waste soils excavated from various depths in a semiarid region under rainfall and wind erosive forces. Soil samples excavated from the topsoil (0–0.3 m) and subsoil layers (0.3–0.9 and > 1 m depths) were subjected to simulated rainfall and wind. Under rainfall erosive forces, the subsoils were more erodible than the topsoil, in contrast to the results obtained under wind erosive forces. Exchangeable sodium percentage was the main factor controlling soil erodibility (K_i) under rainfall, and a significant logarithmic regression line was found between these two parameters. In addition, a significant, linear regression was found between K_i and slaking values for the studied soil samples, suggesting that the former can be predicted from the latter. Soil erodibility under wind erosion force was controlled mainly by the dry aggregate characteristics (mean weight diameter and aggregate density): their higher values in the subsoil layers resulted in lower soil erodibility compared to the topsoil.