干旱区生态环境知识资源中心(Arid): Transient Bedload Transport During Flashflood Bores in a Desert Gravel-Bed Channel

Arid

DOI	10.1029/2022WR033754
	Transient Bedload Transport During Flashflood Bores in a Desert Gravel-Bed Channel
	Halfi, Eran; Thappeta, Suresh K.; Johnson, Joel P. L.; Reid, Ian; Laronne, Jonathan B.
通讯作者	Halfi, E
来源期刊	WATER RESOURCES RESEARCH
ISSN	0043-1397
EISSN	1944-7973
出版年	2023
卷号	59 期号:6
英文摘要	Evidence of the effect of unsteady flow on bedload sediment transport is meager, particularly in desert rivers, despite its scientific, environmental and engineering importance. Our study of the phenomenon was conducted in Nahal Eshtemoa, Israel, an ephemeral river located in a semi-arid area and subjected to flash floods. During 4 years, we monitored bedload transport and contemporaneous hydraulics, focusing on two intervals during which flow changed most rapidly: (a) the arrival of flood bores over dry river beds and (b) the propagation of subsequent bores over flowing water. Monitoring involved deployment of plate microphones, video cameras, surface velocity radar and a 3D velocimeter, enabling synchronized and unique data acquisition at high temporal resolution. We hypothesized that turbulence would be considerably elevated during the arrival of a flood bore and that this would induce transient entrainment of bedload. Our results demonstrate that bedload is indeed transported by the bore front and ceases soon after the arrival of most bores, even though water depth continues to rise. Bores arriving on a dry river bed usually generate higher bedload fluxes than bores advancing over flowing water. Elevated values of shear stress, turbulent kinetic energy and water-surface slope occur as a bore impinges but then decrease. This is likely to be the explanation for high transient rates of bedload transport. Once the threshold depth previously determined as inducing continuous bedload motion is attained (approximate to 40 cm), transport rates rise considerably relative to those associated with the bores.
英文关键词	bedload bore turbulence flash flood unsteady flow gravel bed channel
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:001004454600001
WOS关键词	SEDIMENT TRANSPORT ; LOAD TRANSPORT ; SHEAR-STRESS ; FLOOD ; TURBULENCE
WOS类目	Environmental Sciences ; Limnology ; Water Resources
WOS研究方向	Environmental Sciences & Ecology ; Marine & Freshwater Biology ; Water Resources
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/399153
推荐引用方式 GB/T 7714	Halfi, Eran,Thappeta, Suresh K.,Johnson, Joel P. L.,et al. Transient Bedload Transport During Flashflood Bores in a Desert Gravel-Bed Channel[J],2023,59(6).
APA	Halfi, Eran,Thappeta, Suresh K.,Johnson, Joel P. L.,Reid, Ian,&Laronne, Jonathan B..(2023).Transient Bedload Transport During Flashflood Bores in a Desert Gravel-Bed Channel.WATER RESOURCES RESEARCH,59(6).
MLA	Halfi, Eran,et al."Transient Bedload Transport During Flashflood Bores in a Desert Gravel-Bed Channel".WATER RESOURCES RESEARCH 59.6(2023).