气候变化领域集成服务门户(CCPortal): Mud in rivers transported as flocculated and suspended bed material

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DOI	10.1038/s41561-020-0602-5
	Mud in rivers transported as flocculated and suspended bed material
	Lamb M.P.; de Leeuw J.; Fischer W.W.; Moodie A.J.; Venditti J.G.; Nittrouer J.A.; Haught D.; Parker G.
发表日期	2020
ISSN	17520894
起始页码	566
结束页码	570
卷号	13 期号:8
英文摘要	Riverine transport of silt and clay particles—or mud—builds continental landscapes and dominates the fluxes of sediment and organic carbon across Earth’s surface. Compared with fluxes of sand-sized grains, mud fluxes are difficult to predict. Yet, understanding the fate of muddy river sediment is fundamental to the global carbon cycle, coastal landscape resilience to sea-level rise, river restoration and river–floodplain morphodynamics on Earth and Mars. Mechanistic theories exist for suspended sand transport, but mud in rivers is often thought to constitute washload—sediment with settling velocities so slow that it does not interact with the bed, such that it depends only on upstream supply and is impossible to predict from local hydraulics. To test this hypothesis, we compiled sediment concentration profiles from the literature from eight rivers and used an inversion technique to determine settling rates of suspended mud. We found that mud in rivers is largely flocculated in aggregates that have near-constant settling velocities, independent of grain size, of approximately 0.34 mm s−1, which is 100-fold faster than rates for individual particles. Our findings indicate that flocculated mud is part of suspended bed-material load, not washload, and thus can be physically described by bed-material entrainment theory. © 2020, The Author(s), under exclusive licence to Springer Nature Limited.
英文关键词	carbon cycle; entrainment; flocculation; fluvial deposit; grain size; morphodynamics; mud; organic carbon; sand; sea level change; sediment thickness; sediment transport; settling velocity
语种	英语
来源期刊	Nature Geoscience
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/206800
作者单位	Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, United States; Department of Earth, Environmental and Planetary Sciences, Rice University, Houston, TX, United States; Department of Geography, Simon Fraser University, Burnaby, BC, Canada; School of Environmental Science, Simon Fraser University, Burnaby, BC, Canada; Ven Te Chow Hydrosystems Laboratory, Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Champaign, IL, United States; Department of Geology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
推荐引用方式 GB/T 7714	Lamb M.P.,de Leeuw J.,Fischer W.W.,et al. Mud in rivers transported as flocculated and suspended bed material[J],2020,13(8).
APA	Lamb M.P..,de Leeuw J..,Fischer W.W..,Moodie A.J..,Venditti J.G..,...&Parker G..(2020).Mud in rivers transported as flocculated and suspended bed material.Nature Geoscience,13(8).
MLA	Lamb M.P.,et al."Mud in rivers transported as flocculated and suspended bed material".Nature Geoscience 13.8(2020).