title: Rare earth elements tracing the soil erosion processes on slope surface under natural rainfall.
abstract: A field experiment using rare earth elements (REEs) as tracers was conducted to investigate soil erosion processes on slope surfaces during rainfall events. A plot of 10m×2m×0.16m with a gradient of 20° (36.4%) was established and the plot was divided into two layers and four segments. Various REE tracers were applied to the different layers and segments to determine sediment dynamics under natural rainfall. Results indicated that sheet erosion accounted for more than 90% of total erosion when the rainfall amount and density was not large enough to generate concentrated flows. Sediment source changed in different sections on the slope surface, and the primary sediment source area tended to move upslope as erosion progressed. In rill erosion, sediment discharge mainly originated from the toe-slope and moved upwards as erosion intensified. The results obtained from this study suggest that multi-REE tracer technique is valuable in understanding the erosion processes and determining sediment sources.
authors.affiliation: Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, PR China.
authors.forename: Mingyong
authors.initials: M
authors.lastname: Zhu
authors.forename: Shuduan
authors.initials: S
authors.lastname: Tan
authors.forename: Haishan
authors.initials: H
authors.lastname: Dang
authors.forename: Quanfa
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D002681:China; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry; D028581:Lanthanoid Series Elements / Q000032:analysis*; D011891:Rain; D012987:Soil / Q000737:chemistry*
chemical_list: D028581:Lanthanoid Series Elements; D012987:Soil