Publication date: 1 August 2017
Source:Geoderma, Volume 299
Author(s): X.C. Zhang, M.A. Nearing, J.D. Garbrecht
Increasing interest in developing process-based erosion models requires better understanding of the relationships among soil detachment, transportation, and deposition. The objectives are to 1) identify the limiting process between soil detachment and sediment transport for interrill erosion, 2) understand the dynamic relationships between transport and deposition by tracking sediment fate with multiple tracers, and 3) verify the effects of slope length on interrill soil erosion. Five rare earth element (REE) tracers were applied in five bands or segments to track sediment dynamics on a 10%, 4steady state sediment discharge from a segment was positively correlated to the amount of sediment deposited downslope from that segment, implying that 1) re-detachment, transport, and deposition occurred simultaneously in the system and 2) sediment was transported in a form of bedload, mainly rolling or creeping on interrill areas. Sediment delivery ratios of each segment tended to slightly increase downslope, suggesting the flow-driven transport was more efficient than the raindrop-driven transport. The sequence of sediment discharged from different slope positions was inconsistent with the transport-distance theory. However, interrill erosion processes vary with soil, slope, and rainfall properties, and the findings here need to be verified in different conditions.
Source:Geoderma, Volume 299
Author(s): X.C. Zhang, M.A. Nearing, J.D. Garbrecht