Global S&T Development Trend Analysis Platform of Resources and Environment
DOI | 10.1073/pnas.1612907114 |
Sediment supply controls equilibrium channel geometry in gravel rivers | |
Pfeiffer, Allison M.1; Finnegan, Noah J.1; Willenbring, Jane K.2 | |
2017-03-28 | |
发表期刊 | PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
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ISSN | 0027-8424 |
出版年 | 2017 |
卷号 | 114期号:13页码:3346-3351 |
文章类型 | Article |
语种 | 英语 |
国家 | USA |
英文摘要 | In many gravel-bedded rivers, floods that fill the channel banks create just enough shear stress to move the median-sized gravel particles on the bed surface (D-50). Because this observation is common and is supported by theory, the coincidence of bankfull flow and the incipient motion of D50 has become a commonly used assumption. However, not all natural gravel channels actually conform to this simple relationship; some channels maintain bankfull stresses far in excess of the critical stress required to initiate sediment transport. We use a database of > 300 gravel-bedded rivers and > 600 10Be-derived erosion rates from across North America to explore the hypothesis that sediment supply drives the magnitude of bankfull shear stress relative to the critical stress required to mobilize the median bed surface grain size (tau*(bf) = tau*(c))We find that tau*(bf) = tau*(c) is significantly higher in West Coast river reaches (2.35, n = 96) than in river reaches elsewhere on the continent (1.03, n = 245). This pattern parallels patterns in erosion rates (and hence sediment supplies). Supporting our hypothesis, we find a significant correlation between upstream erosion rate and local tau*(bf) = tau*(c) at sites where this comparison is possible. Our analysis reveals a decrease in bed surface armoring with increasing tau*(bf) = tau*(c), suggesting channels accommodate changes in sediment supply through adjustments in bed surface grain size, as also shown through numerical modeling. Our findings demonstrate that sediment supply is encoded in the bankfull hydraulic geometry of gravel bedded channels through its control on bed surface grain size. |
英文关键词 | river channel geometry sediment supply sediment transport |
领域 | 地球科学 ; 气候变化 ; 资源环境 |
收录类别 | SCI-E |
WOS记录号 | WOS:000397607300051 |
WOS关键词 | BED-LOAD TRANSPORT ; SURFACE TEXTURES ; BEDROCK RIVERS ; TIME SCALES ; STREAMS ; EROSION ; BEDLOAD ; CALIFORNIA ; MORPHOLOGY ; CLIMATE |
WOS类目 | Multidisciplinary Sciences |
WOS研究方向 | Science & Technology - Other Topics |
URL | 查看原文 |
引用统计 | |
文献类型 | 期刊论文 |
条目标识符 | http://119.78.100.173/C666/handle/2XK7JSWQ/204683 |
专题 | 地球科学 资源环境科学 气候变化 |
作者单位 | 1.Univ Calif Santa Cruz, Dept Earth & Planetary Sci, Santa Cruz, CA 95064 USA; 2.Univ Calif San Diego, Scripps Inst Oceanog, San Diego, CA 92037 USA |
推荐引用方式 GB/T 7714 | Pfeiffer, Allison M.,Finnegan, Noah J.,Willenbring, Jane K.. Sediment supply controls equilibrium channel geometry in gravel rivers[J]. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA,2017,114(13):3346-3351. |
APA | Pfeiffer, Allison M.,Finnegan, Noah J.,&Willenbring, Jane K..(2017).Sediment supply controls equilibrium channel geometry in gravel rivers.PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA,114(13),3346-3351. |
MLA | Pfeiffer, Allison M.,et al."Sediment supply controls equilibrium channel geometry in gravel rivers".PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 114.13(2017):3346-3351. |
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