DOI: 10.5194/hess-20-3581-2016
Scopus记录号: 2-s2.0-84986275120
论文题名: Using radon to understand parafluvial flows and the changing locations of groundwater inflows in the Avon River, southeast Australia
作者: Cartwright I ; , Hofmann H
刊名: Hydrology and Earth System Sciences
ISSN: 10275606
出版年: 2016
卷: 20, 期: 9 起始页码: 3581
结束页码: 3600
语种: 英语
Scopus关键词: Banks (bodies of water)
; Budget control
; Floods
; Groundwater
; Hydrogeology
; Location
; Rivers
; Sediments
; Stream flow
; Surface waters
; Alluvial sediments
; Coarse-grained sediments
; Floodplain sediments
; Gas transfer coefficients
; Ground water inflow
; Hyporheic exchange
; Riverine ecosystems
; Southeast australia
; Water resources
; alluvial deposit
; floodplain
; groundwater flow
; groundwater-surface water interaction
; inflow
; radon
; streamflow
; surface water
; Australia
; Avon River [England]
; England
; United Kingdom
英文摘要: Understanding the location and magnitude of groundwater inflows to rivers is important for the protection of riverine ecosystems and the management of connected groundwater and surface water systems. This study utilizes 222Rn activities and Cl concentrations in the Avon River, southeast Australia, to determine the distribution of groundwater inflows and to understand the importance of parafluvial flow on the 222Rn budget. The distribution of 222Rn activities and Cl concentrations implies that the Avon River contains alternating gaining and losing reaches. The location of groundwater inflows changed as a result of major floods in 2011-2013 that caused significant movement of the floodplain sediments. The floodplain of the Avon River comprises unconsolidated coarse-grained sediments with numerous point bars and sediment banks through which significant parafluvial flow is likely. The 222Rn activities in the Avon River, which are locally up to 3690Bq & m-3, result from a combination of groundwater inflows and the input of water from the parafluvial zone that has high 222Rn activities due to 222Rn emanation from the alluvial sediments. If the high 222Rn activities were ascribed solely to groundwater inflows, the calculated net groundwater inflows would exceed the measured increase in streamflow along the river by up to 490% at low streamflows. Uncertainties in the 222Rn activities of groundwater, the gas transfer coefficient, and the degree of hyporheic exchange cannot explain a discrepancy of this magnitude. The proposed model of parafluvial flow envisages that water enters the alluvial sediments in reaches where the river is losing and subsequently re-enters the river in the gaining reaches with flow paths of tens to hundreds of metres. Parafluvial flow is likely to be important in rivers with coarse-grained alluvial sediments on their floodplains and failure to quantify the input of 222Rn from parafluvial flow will result in overestimating groundwater inflows to rivers. © Author(s) 2016. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/78743
Appears in Collections: 气候变化事实与影响
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作者单位: School of Earth, Atmosphere and Environment, Monash University, Clayton, VIC, Australia; National Centre for Groundwater Research and Training, Flinders University, GPO Box 2100, Adelaide, SA, Australia; School of Earth Sciences, University of Queensland, St. Lucia, QLD, Australia
Recommended Citation:
Cartwright I,, Hofmann H. Using radon to understand parafluvial flows and the changing locations of groundwater inflows in the Avon River, southeast Australia[J]. Hydrology and Earth System Sciences,2016-01-01,20(9)