Morphological characteristics of gullies affected by the soil type of artificial slopes in the Dry‐hot Valley Region, Southwest China

Abstract

Gully erosion is widely recognized as a significant form of land degradation globally, posing threats to ecological security and human societal development because of its ability to generate substantial amount of sediment. Artificial slopes are commonly disturbed landforms that are susceptible to intensive gully erosion. Morphological characteristics play a crucial role in assessing the intensity of gully erosion and can be utilized to predict sediment yield. Notably, soil type has been identified as a key factor influencing the morphological characteristics of gullies. Consequently, a comprehensive analysis was conducted based on meticulous field investigations to examine the impact of soil type on the morphological characteristics of gullies on artificial slopes in the Dry‐hot Valley Region of Southwest China. The results showed that the gully cross‐sectional area (Ac), curvature (Cc), and shape index (Si) exhibited a decrease along the downslope direction of the artificial slopes for all three studied soil types, following power functions. Additionally, the soil type of the artificial slope significantly influenced the mean values of the gully cross‐sectional morphological characteristics. Regarding the longitudinal morphological characteristics of the gullies, the largest longitudinal concavity (Ca), longitudinal curvature (Cl), and length‐gradient index (Gl) values were observed for the Vertisol, Entisol, and Ferrasol, respectively. These findings suggested that gullies developed on different soil types exhibit significant variations, particularly in terms of longitudinal morphological characteristics. Furthermore, strong correlations were detected between the gully cross‐sectional and longitudinal profile morphological characteristics, and the gully cross‐sectional shape index (Si) was correlated with all the longitudinal profile morphological characteristics. This study offers valuable insights into the morphological characteristics of gullies on artificial slopes with different soil types. Such knowledge is of paramount importance for effectively preventing and controlling gully erosion in contemporary society.