Effects of Taproot-Type and Fibrous-Root-Type Grass Cover Structures on Runoff and Sediment Yield Processes on Slopes in the Loess Hilly and Gully Region

作者：Zimiao He, Gangxiang Yuan, Haoqiang Tong, Shilong Hao, Zhe Liu, Ran Wei, Ting Li, Yinghong Guo, Douhuan Heng, Peiqing Xiao · 年份：2025 · DOI：10.22541/au.175672496.61737191/v1 · 研究领域：Soil erosion and sediment transport

Vegetation effects on slope runoff and sediment yield depend on plant types and vertical structures, yet underlying mechanisms remain insufficiently quantified. We conducted simulated rainfall experiments (60, 90, 120 mm h -1 ) on a taproot grass (Coronillavaria) and a fibrous-root grass (Juncuseffusus) to assess canopy and root contributions to runoff and soil loss control. Both species significantly reduced erosion, with sediment reduction exceeding runoff reduction. Compared with bare slopes, runoff decreased by 18.47%–69.27%, and sediment yield by 66.93%–99.77%. Roots dominated the control effect, contributing 54.99%–91.54% for runoff and 54.99%–86.69% for sediment, whereas canopies contributed 3.06%–26.59% and 13.31%–45.01%, respectively. Juncuseffusus roots and canopy achieved mean runoff reduction efficiencies of 53.41% and 5.25%, markedly higher than Coronillavaria (18.40% and 3.06%). In sediment reduction, Juncuseffusus excelled at 90 mm h -1 (83.31% by roots), while Coronillavaria performed better at 60 mm h -1 . Both species decreased soil erodibility (Juncuseffusus 93.13%, Coronillavaria 82.84%) and increased critical shear stress (216.35% and 152.73%). These results highlight the superior runoff and erosion control of fibrous-root species, though dense roots may pose slope-failure risks under prolonged heavy rainfall. This study provides practical guidance for vegetation-based slope stabilization and soil conservation in China’s Loess Hilly and Gully Region.