1,2- 1Key Laboratory of Mountain Hazards and Engineering Resilience, Institute of Mountain Hazards and Environment, Chinese Academy of Science, Chengdu 610213, China
- 2Branch of Sustainable Mountain Development, Kathmandu Center for Research and Education, CAS-TU, Kathmandu 44600, Nepal
- 3Guizhou Minzu University, Guiyang 550025 China
Vegetation plays a crucial role in the control of gully erosion due to its combined impact of root system and the above ground components. However, limited research has been done on the hydrodynamic effects of vegetation in relation to gully erosion. Vegetation, including stems and litter, are key surface roughness factors that greatly influence the flow of water, subsequently impacting sedimentation. In this study, a series of scouring experiments were conducted to investigate the effects of different shrub stem coverages (0%, 0.15%, 0.30%, 0.60%, and 1.20%) and litter coverages (0 g m-2, 100 g m-2, 200 g m-2, 300 g m-2, and 400 g m-2) on the spatiotemporal variations of flow velocity, shear stress, resistance f and sediment concentration under concentrated flow during the gully bed erosion processes in the dry-hot valley region of Jinsha River, Southwest China. The results showed that the number of branches in the vegetated plots increased significantly from upstream to downstream as stem coverage and litter coverage increased. Compared with bare gully bed, the flow velocity and shear stress of the four stem coverages decreased by 17% ~ 61% and 2% ~ 23%, respectively. These reductions were more significant as stem coverage and litter accumulation increased. The resistance f increased 0.14~5.8 times as stem cover and litter coverage increased, and the increase was more obvious along with the extending direction of gully bed. The sediment concentration decreased with increasing stem cover and litter coverage. The split flow effects under different shrub stem and litter coverages significantly affected the spatiotemporal variation of soil loss and hydraulic properties during gully bed erosion processes. Overall, increasing shrub planting in gully beds is essential to mitigate gully bed erosion, and the effects generally are enhanced with increasing stem litter and cover in gully beds.
How to cite: Xiong, D. and Liu, L.: Hydraulic properties and sediment yield as affected by different shrub stem and litter coverages during gully bed erosion processes , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-4418, https://doi.org/10.5194/egusphere-egu26-4418, 2026.
