干旱区生态环境知识资源中心(Arid): Biotic forcing militates against river meandering in the modern Bonneville Basin of Utah

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DOI	10.1111/sed.12562
	Biotic forcing militates against river meandering in the modern Bonneville Basin of Utah
	Ielpi, Alessandro 1; Lapotre, Mathieu G. A.2
通讯作者	Ielpi, Alessandro
来源期刊	SEDIMENTOLOGY
ISSN	0037-0746
EISSN	1365-3091
出版年	2019
卷号	66 期号:5 页码:1896-1929
英文摘要	Biotic forcing on river meandering is a highly debated topic in sedimentology. Vegetation is assumed to hold a vital role on channel stability and sinuosity, for example through bank stabilization and pedogenic production of cohesive clays. However, statistically solid and causal relationships between vegetation density and river sinuosity remain largely untested in natural systems. This study investigates physical and biotic forcings on channel sinuosity in the Bonneville Basin of Utah (USA), an endorheic depression flanked by active fluvial networks ('washes') that display diverse vegetation density and channel-planform style. By means of remote sensing and ground-data collection, 58 washes are considered, 0 center dot 1 to 90 km(2) in surface area and drained by trunk channels <45 m wide and <1 center dot 2 m deep. Each wash is composed of a catchment basin connected downstream to an aggradational and distributive channel network. Statistically solid regressions highlight the primary roles played by base level and catchment size on fluvial morphogenesis. In contrast, no correlation is found between vegetation density and other parameters such as trunk-channel width or surface area of the largest meander in a wash. Similarly, no statistical correlation exists between vegetation density and meander size or sinuosity index. Rather, larger and more sinuous meanders are invariably associated with lower vegetation density. These results are corroborated by field evidence showing that sparse vegetation promotes flow disturbance, channel branching and bar braiding instead of stabilizing sediment surfaces. Thus, river meandering is attributed to cohesion offered by mud retention within the endorheic basin, as well as discharge and stream-power modulation along bifurcating and low-gradient channel reaches. Hence, this work demonstrates how meandering-channel patterns may arise from entirely physical forcings in the absence of vegetation.
英文关键词	Biogeomorphology desert fluvial Great Salt Lake sinuosity vegetation
类型	Article
语种	英语
国家	Canada ; USA
收录类别	SCI-E
WOS记录号	WOS:000477915100016
WOS关键词	GREAT-SALT-LAKE ; EARLY LAND PLANTS ; FLUVIAL SEDIMENT ; ENVIRONMENTAL CONTROLS ; RIPARIAN VEGETATION ; JOGGINS FORMATION ; EPHEMERAL RIVER ; FLOW STRUCTURE ; POINT BARS ; RIO-TINTO
WOS类目	Geology
WOS研究方向	Geology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/218826
作者单位	1.Laurentian Univ, Harquail Sch Earth Sci, Sudbury, ON P3E 2C6, Canada; 2.Harvard Univ, Dept Earth & Planetary Sci, 20 Oxford St, Cambridge, MA 02138 USA
推荐引用方式 GB/T 7714	Ielpi, Alessandro,Lapotre, Mathieu G. A.. Biotic forcing militates against river meandering in the modern Bonneville Basin of Utah[J],2019,66(5):1896-1929.
APA	Ielpi, Alessandro,&Lapotre, Mathieu G. A..(2019).Biotic forcing militates against river meandering in the modern Bonneville Basin of Utah.SEDIMENTOLOGY,66(5),1896-1929.
MLA	Ielpi, Alessandro,et al."Biotic forcing militates against river meandering in the modern Bonneville Basin of Utah".SEDIMENTOLOGY 66.5(2019):1896-1929.