气候变化领域集成服务门户(CCPortal): Density-dependent solute transport in a layered hyporheic zone

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DOI	10.1016/j.advwatres.2020.103645
	Density-dependent solute transport in a layered hyporheic zone
	Jiang Q.; Jin G.; Tang H.; Shen C.; Cheraghi M.; Xu J.; Li L.; Barry D.A.
发表日期	2020
ISSN	0309-1708
卷号	142
英文摘要	Hyporheic exchange is affected by bedform geometry, which induces complex flow paths within the bedform. Additional factors that influence flow and solute transport in the hyporheic zone are layered profile sediments and density-driven flow. This study explored the combined effects of these factors on hyporheic exchange through laboratory experiments and numerical simulations involving infiltrating solute displacing less-dense resident water in a layered bedform with a low permeability layer (LPL). The bedform consisted of three horizontal layers, in which the hydraulic conductivity of the middle layer (LPL) was less than that of the top (TL) and bottom layers (BL). The results demonstrated that a previously unexplored combination of mechanisms (density effects and layered bedform) produces irregular spatial patterns of solute transport in the hyporheic zone. For instance, the width of solute plume within the bottom layers becomes narrowed compared with tracer transport. With increasing density contrast between infiltrating solute and resident water, the solute plume becomes much narrower, forming fingers. Numerical modeling further shows that the hydraulic conductivity contrast (HCC) and relative thickness (RT) of the hyporheic zone layers also affect the spatial solute transport patterns. As the hydraulic conductivity contrast or relative thickness increases, the plume becomes much narrower. Horizontal ambient flow (HAF) dominated in the bottom layers, and lateral solute spreading and mixing intensified with a higher hydraulic conductivity contrast and relative thickness. Furthermore, the vertical solute plume was detached by the horizontal ambient flow in the bottom layers with a discontinuous low permeability layer, forming a discontinuous zone of vertical solute transport. © 2020
关键词	Hydraulic conductivity Infiltration Numerical models Stream flow Density dependent Density driven flows Horizontal layers Hyporheic exchange Laboratory experiments Low permeability Relative thickness Transport patterns Solute transport
语种	英语
来源机构	Advances in Water Resources
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/131753
推荐引用方式 GB/T 7714	Jiang Q.,Jin G.,Tang H.,et al. Density-dependent solute transport in a layered hyporheic zone[J]. Advances in Water Resources,2020,142.
APA	Jiang Q..,Jin G..,Tang H..,Shen C..,Cheraghi M..,...&Barry D.A..(2020).Density-dependent solute transport in a layered hyporheic zone.,142.
MLA	Jiang Q.,et al."Density-dependent solute transport in a layered hyporheic zone".142(2020).