DOI: 10.1002/2015GL066097
论文题名: Coarser and rougher: Effects of fine gravel pulses on experimental step-pool channel morphodynamics
作者: Johnson J.P.L. ; Aronovitz A.C. ; Kim W.
刊名: Geophysical Research Letters
ISSN: 0094-9284
EISSN: 1944-9015
出版年: 2015
卷: 42, 期: 20 起始页码: 8432
结束页码: 8440
语种: 英语
英文关键词: gravel augmentation
; morphodynamics
; river restoration
; step-pool channel
Scopus关键词: Grain size and shape
; Lakes
; Rivers
; Sediments
; Channel morphodynamics
; Flume experiment
; Grain size distribution
; Gravel augmentation
; Morphodynamics
; Natural conditions
; River restoration
; step-pool channel
; Gravel
; bed roughness
; clast
; environmental restoration
; experimental design
; extreme event
; grain size
; gravel
; morphodynamics
; perturbation
; river bed
; sediment transport
; size distribution
英文摘要: Understanding how steep mountain rivers respond to natural and anthropogenic sediment supply perturbations is important for predicting effects of extreme events (e.g., floods and landslides) and for restoring rivers to more natural conditions. Using flume experiments, we show that stabilized step-pool-like channel beds can respond to pulses of finer gravel by becoming even coarser and rougher than before. Adding finer gravel initially reduces bed roughness and also increases the mobility of previously stable bed grains. Small- and intermediate-diameter clasts are then preferentially winnowed from the bed surface, leaving behind higher concentrations of even larger clasts. Ultimately, this results in both a coarser and rougher bed. Our experiments demonstrate that steep river beds become stable through the coevolution of bed roughness and surface grain size distribution and that these morphological variables can be sensitive to the history of upstream sediment supply. Key Points Fine gravel pulses can mobilize coarser bed surface grains Fine gravel pulses can coarsen and roughen mountain river beds The history of sediment supply influences stable bed morphology © 2015. American Geophysical Union. All Rights Reserved. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84946549337&doi=10.1002%2f2015GL066097&partnerID=40&md5=7e25b51d621a001c13bf7d24f71ff65b
Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/8900
Appears in Collections: 科学计划与规划 气候变化与战略
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作者单位: Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin, Austin, TX, United States
Recommended Citation:
Johnson J.P.L.,Aronovitz A.C.,Kim W.. Coarser and rougher: Effects of fine gravel pulses on experimental step-pool channel morphodynamics[J]. Geophysical Research Letters,2015-01-01,42(20).