Open Access

ARTICLE

Separation and Transport of Sediment Particles Due to the Erosion of Sand-Covered Slopes

Shanshan Tang^1,2,*, Zhanbin Li^3,4, Xubin Zhu^1,2, Peng Li³, Zhaoyang Feng^1,2, Guoliang Yang^1,2, Huake Chang^1,2, Zefeng Che^1,2

1 Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Areas, Guilin University of Technology, Guilin, 541004, China
2 College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China
3 State Key Laboratory of Eco-Hydraulics in Northwest Arid Region of China, Xi’an University of Technology, Xi’an, 710048, China
4 State Key Laboratory of Soil Erosion and Dry-Land Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, 712100, China

* Corresponding Author: Shanshan Tang. Email:

Fluid Dynamics & Materials Processing 2025, 21(4), 819-831. https://doi.org/10.32604/fdmp.2025.057605

Received 22 August 2024; Accepted 20 December 2024; Issue published 06 May 2025

Abstract

The particle size distribution plays a crucial role in the transportation and deposition of eroded sediments. Gaining insights into the related sorting mechanism can significantly enhance our understanding of such processes. In this study, sand-covered slopes were examined. A controlled indoor rainfall simulation was conducted on loess slopes with a 12° incline and a rainfall intensity of 1.5 mm/min. These slopes were then covered with sand layers of varying thicknesses—0.5, 1.0, and 1.5 cm—to observe their effects. The findings have revealed that as the thickness of the sand cover increases, the content of sediment particles smaller than 0.054 mm decreases. In contrast, the content of particles larger than 0.054 mm increases after the sixth minute of runoff. The eroded sediment was predominantly composed of silt. During the inter-rill erosion stage, runoff primarily transported particles larger than 0.054 mm. However, in the subsequent rill erosion and combined rill and inter-rill erosion stages, the runoff predominantly carried finer particles, smaller than 0.054 mm. Moreover, the presence of the sand layer significantly influenced the size and form of the eroded sediment particles. Initially, during the first 10 min of runoff, the eroded particles were predominantly larger than 0.054 mm. After this period, however, the particle size shifted, with the majority of particles being smaller than 0.054 mm. This study highlights the intricate relationship between sediment sorting, the thickness of sand covers, and the dynamics of sediment transport under rainfall-induced erosion.

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Keywords

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