An experimental investigation of the erosion process and morphological characteristics of the tile-back type slope with non-uniform slopes based on a 3D reconstruction method. (1st January 2023)

• Record Type: Journal Article
• Authors: Guo, Huili; Sun, Liquan; Wu, Shufang; Feng, Hao; Biswas, Asim; Siddique, Kadambot H.M.
• Is Part Of: Journal of environmental management. Volume 325:Part B(2023)
• Publication Date: 2023-01-01
• Subjects: Spatial distribution characteristics of soil erosion -- Ephemeral gully erosion -- 3D reconstruction method -- Rainfall simulation -- Morphology characteristics; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2022.116558
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: Tile-back type slopes comprise ephemeral gullies (EGs) and hillslopes; they are a unique and widely distributed micro-landform in the Loess Plateau region of China. Gully erosion from these landforms is a serious issue, but the micro-landform makes the erosion process and its estimation complex. Quantifying soil erosion processes and their distribution characteristics at different positions on tile-back type slopes will provide a clearer picture for ecological restoration to control further soil degradation. This study investigated the erosion process of tile-back type slope with non-uniform slopes using a 3D photo-reconstruction method during eight successive simulated rainfall events. The results showed that EG erosion began with a chain of intermittent headcuts. When the accumulated rainfall reached 76 mm, serious collapses dramatically increased the amount of sediment by 216% after the first rainfall (cumulative rainfall was about 15 mm). We quantified the sediment contribution of EG erosion (46.20%), rill erosion (35.62%), and inter-rill erosion (18.18%) to total soil loss. The erosion area of the steep slope section and extremely steep slope section accounted for 33.26% and 66.74% of the total erosion area, respectively. Moreover, sediment amounts significantly correlated with morphological parameters, particularly the amount of EG erosion and maximum gully depth, with a correlation coefficient of 0.98. Cumulative gully length and erosion area had the greatest effect on rill erosion, with a correlation coefficient of 0.97. These results provide insight into the qualitative and quantitative understanding of EG erosion process on Loess Plateau of China and an important reference for the rational arrangement of EG control measures. Highlights: An experimental investigate of erosion process of a unique and widely distributed micro-landform in the Loess Plateau region of China. EG erosion, rill erosion and inte-rrill erosion accounted for 46.20%, 35.26% and 18.18% of the total sediment, respectively. The erosion area of extremely steep slope sections accounted for the largest proportion of the total erosion area. The widthmean, cumulative length, average width/depth ratio, depthmax, and erosion area were used to describe the morphological change.