Influence of riparian vegetation on channel widening and subsequent contraction on a sand-bed stream since European settlement: Widden Brook, Australia

Erskine, Wayne D.; Keene, Annabelle F; Bush, Richard T; Cheetham, Michael D; Chalmers, Anita

doi:10.1016/j.geomorph.2011.07.030

Cited by 35 publications

(33 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Many previous studies show that riparian vegetation can prevent bank failure due to root reinforcement of the soil [19]. This can also be beneficial for fluvial ecosystems [20]. Chen et al [21] conducted a set of flume experiments, with submerged instream vegetation of different densities, to assess the change in flow hydrodynamics, including velocity and turbulence, and the impact on local scouring around vegetation elements.…”

Section: Introductionmentioning

confidence: 99%

Flow Hydrodynamics across Open Channel Flows with Riparian Zones: Implications for Riverbank Stability

Valyrakis

Williams

2017

Water

View full text Add to dashboard Cite

Riverbank vegetation is of high importance both for preserving the form (morphology) and function (ecology) of natural river systems. Revegetation of riverbanks is commonly used as a means of stream rehabilitation and management of bank instability and erosion. In this experimental study, the effect of different riverbank vegetation densities on flow hydrodynamics across the channel, including the riparian zone, are reported and discussed. The configuration of vegetation elements follows either linear or staggered arrangements as vegetation density is progressively increased, within a representative range of vegetation densities found in nature. Hydrodynamic measurements including mean streamwise velocity and turbulent intensity flow profiles are recorded via acoustic Doppler velocimetry (ADV)-both at the main channel and within the riverbank. These results show that for the main channel and the toe of riverbank, turbulence intensity for the low densities (λ ≈ 0 to 0.12 m −1 ) can increase up to 40% compared the case of high densities (λ = 0.94 to 1.9 m −1 ). Further analysis of these data allowed the estimation of bed-shear stresses, demonstrating 86% and 71% increase at the main channel and near the toe region, for increasing densities (λ = 0 to 1.9 m −1 ). Quantifying these hydrodynamic effects is important for assessing the contribution of physically representative ranges of riparian vegetation densities on hydrogeomorphologic feedback.

show abstract

Section: Introductionmentioning

confidence: 99%

Flow Hydrodynamics across Open Channel Flows with Riparian Zones: Implications for Riverbank Stability

Valyrakis

Williams

2017

Water

View full text Add to dashboard Cite

show abstract

“…Meanders create a low velocity zone adjacent to point bars that form through deposition of bedload and later suspended sediment. Vegetation growing on deposited coarse bedload material increases stability and roughness, decreases flow velocities, increases deposition of finer suspended sediment (figures 2e and 3b to 3g) (Robertson and Augspurger 1999;Steiger and Gurnell 2003;Rood et al 2003;Robertson 2006;Polzin and Rood 2006), and encourages meander development (Erskine et al 2009(Erskine et al , 2012Rominger et al 2010;Tal and Paola 2010), which decreases stream gradient and power (Bagnold 1966). Deposition of fine alluvial soil facilitates revegetation while it removes water pollution.…”

Section: Geomorphologymentioning

confidence: 99%

Riparian proper functioning condition assessment to improve watershed management for water quality

Swanson¹,

Kozlowski²,

Hall³

et al. 2017

Journal of Soil and Water Conservation

View full text Add to dashboard Cite

Pollutants can be reduced, ameliorated, or assimilated when riparian ecosystems have the vegetation, water, and soil/landform needed for riparian functions. Loss of physical form and ecological function unravels assimilation processes, increasing supply and transport of pollutants. Water quality and aquatic organisms are response measures of accumulated upstream discharges, and ultimately of changes in riparian functions. Thus, water quality monitoring often fails to identify or lags behind many causes of pollution or remediation from riparian degradation. This paper reviews the interagency riparian proper functioning condition (PFC) assessment for lotic (running water) riparian ecosystems and outlines connections between PFC and water quality attributes (sediment, nutrients, temperature, and dissolved oxygen [DO]). The PFC interaction of hydrology, vegetation, and soils/landforms influences water quality by dissipating energy associated with high waterflow, thereby reducing vertical instability and lateral erosion while developing floodplains with captured sediment and nutrients. Slowing flood water enables aquifer recharge, deposition, and plant nutrient uptake. Water-loving, densely rooted streambank stabilizing vegetation and/or wood helps integrate riparian functions to maintain channel pattern, profile, and dimension with characteristics for a diversity of habitats. A complex food web helps slow the nutrient spiral with uptake and storage. Temperature fluctuations are dampened by delayed discharges, narrower and deeper active channels, coarser substrates that enhance hyporheic interchange, and shade from riparian vegetation. After assessment and implementation, monitoring recovery of impaired riparian function attributes (e.g., streambank plant species) naturally focuses on persistent drivers of water quality and aquatic habitat. This provides timely environmental indicators of stream ecological health and water quality remediation projects or land management. Key words: environmental indicators-function-nutrients-rivers and streamssediment-temperatureWater quality standards are based on needs for beneficial uses, whereas opportunities for remediation are often based on need(s) for riparian functions. Water quality or biological community assessments (USEPA 2009a(USEPA , 2009b cannot predict if an ecosystem is crossing geomorphic or ecological thresholds causing devastating changes to the riparian and aquatic ecosystems (Hall et al. 2014;Kozlowski et al. 2013). For nonpoint source issues, water quality data are lagging indicators (response indicators) and do not inform riparian resource managers or riparian restoration monitors in a timeframe relevant for adaptive management. Water quality and many other terrestrial and aquatic ecosystem goods and services depend on riparian functions. One of the goals of many federal, state, and tribal environmental and natural resource programs is to maintain and restore functionality of stream and wetland riparian areas. This impacts sediment and nutrient loa...

show abstract

“…Not only did riparian clearing make banks more susceptible to erosion, it exacerbated the invasion of exotic willows, which were planted to stabilise banks. The channel narrowing effect of willows has, in some smaller channels, led to severe erosion where willow infested reaches are bypassed by cutoffs or avulsions (Brizga & Finlayson 1990;Pope et al 2007;Erskine et al 2012).…”

Section: Geomorphic Responses To Anthropogenic Activitymentioning

confidence: 99%

Interaction of ENSO-driven Flood Variability and Anthropogenic Changes in Driving Channel Evolution: Corryong/Nariel Creek, Australia

Teo

Marren

2015

Australian Geographer

View full text Add to dashboard Cite

Influence of riparian vegetation on channel widening and subsequent contraction on a sand-bed stream since European settlement: Widden Brook, Australia

Cited by 35 publications

References 39 publications

Flow Hydrodynamics across Open Channel Flows with Riparian Zones: Implications for Riverbank Stability

Flow Hydrodynamics across Open Channel Flows with Riparian Zones: Implications for Riverbank Stability

Riparian proper functioning condition assessment to improve watershed management for water quality

Interaction of ENSO-driven Flood Variability and Anthropogenic Changes in Driving Channel Evolution: Corryong/Nariel Creek, Australia

Contact Info

Product

Resources

About