8/11/2013
Trade Mark and Accreditation
• River Styles® Framework is Trade Marked The River Styles Framework through AccessMQ (framework to be applied by a provisional/accredited River Styler)
Gary Brierley and Kirstie Fryirs • Provisional River Styler … with comments, extensions by Joe Wheaton (= passed River Styles® Short Course)
• Accredited River Styler (= River Styles® report reviewed and passed) www.riverstyles.com
A nested hierarchy of spatial and temporal linkages Stage One: Identifying and Catchment / interpreting River Styles subcatchment Describe river character and behaviour • River Styles are differentiated on the basis Landscape Unit of:
Explain evolution and condition – Valley‐setting – Channel planform Reach = River Style – Channel and floodplain geomorphic units Predict future character and behaviour – Bed material texture Geomorphic Unit • Each River Style has a distinctive set of Assess geomorphic attributes Hydraulic Unit recovery potential
Identification of reach boundaries • Each reach (River Style) has a distinguishing set of attributes • Boundaries between River Styles reflect Valley‐setting – wholesale change in river character and behaviour (differing assemblage of geomorphic units) – may be distinct or gradual – alternating patterns may occur • Confined … Absent or isolated pockets of • May coincide with tributary confluences, changes in slope or valley confinement, etc floodplain • Partly‐confined … Discontinuous pockets of floodplain • Laterally‐unconfined ... Continuous floodplains along both banks – With continuous channels – With discontinuous/absent channels
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Confined valley‐setting Partly‐confined valley‐setting
Bellinger River Upper Tantawangalo Creek
Laterally‐unconfined valley‐setting Measures of channel planform • number of channels – single, multichannelled or no channel
• sinuosity – the amount of meandering exhibited by a stream channel, i.e. channel ‘bendiness’ – S = L/ • L = length of stream along thalweg, • = length of valley along axis
• lateral stability of channel – ability of the channel to adjust its position on the valley floor (lateral migration, thalweg shift, avulsion)
British Columbia
Geomorphic units
• The building blocks of rivers • Form‐process associations – specific relationship between individual landforms and the set of processes that produces them – means to interpret river behaviour, evolution and condition • 4 categories: Measures – instream sculpted (pg 83) of planform – instream depositional (mid‐channel) (pg 87) (from Brierley & Fryirs, – instream depositional (bank‐attached) (pg 94) 2005) – floodplain (pg 110) • Distinct channel and floodplain assemblages for different River Styles
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Instream sculpted or erosional units Instream geomorphic units: Depositional features found in mid‐channel locations
Boulder mound
Longitudinal bar
Waterfall Cascade Diagonal bar
Pool Linguoid bar
These units are often forced
Instream geomorphic units: Depositional features Other mid‐channel geomorphic units found in bank‐attached locations
Island Bedrock core bar Point bar
Sand or gravel sheet Lateral bar
Bench
Floodplain geomorphic unit assemblages Bed material texture levee floodchannel crevasse splay backswamp Class name Grain size (mm) Grain size (phi Grain size (Ø) (Wentworth Bedrock scale) Boulder ≥ 256 ≤ ‐9 Cobble 64 ‐ 256 ‐6 to ‐9 Measure Gravel 2 ‐ 64 ‐1 to ‐6 b‐axis Sand 0.062 ‐ 24 to ‐1 Silt 0.004 – 0.062 8 to 4 Termed Clay ≤ 0.004 ≥ ‐8 fine‐grained
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Identification of River Styles Confined valley‐setting River Styles • Using air photos and the River Styles procedural tree, break the (>90% of the channel margin abuts the valley margin) river course into sections based on: Example of a River Styles tree – Valley‐setting (channel‐valley margin relationship) Procedure – Channel planform (number and sinuosity of channels, lateral Confined valley setting stability of channel) Confined valley setting (>90 % of channel – Instream and floodplain geomorphic units abuts valley margin) no no occasional floodplain floodplain floodplain – Bed material texture (if visible) pockets pockets pockets • Specific procedures are used to identify River Styles in each presence/absence of valley setting waterfalls, cascades, pools, occasional floodplain cascades, rapids, riffles, Confined valley setting Partly-confined valley setting Laterally-unconfined valley setting pockets rapids boulder glides/runs (>90 % of channel (10-90 % of channel abuts (<10 % of channel abuts bars abuts valley margin) valley margin) valley margin) bedrock, bedrock, absent or present and geomorphic units bedrock, presence/absence of degree of lateral confinement and boulder, gravel, occasional floodplain valley configuration discontinuous continuous boulder, channel channel gravel sand pockets (straight vs irregular vs sinuous) gravel geomorphic units river planform geomorphic units river planform bed material texture steep gorge occasional bed material texture geomorphic units valley floor geomorphic units texture headwater floodplain bed material texture bed material texture pockets
Gorge River Style Steep headwater River Style (Franklin River, Tasmania) (Broughton Creek, Shoalhaven catchment)
Confined valley with occasional floodplain pockets Partly‐confined valley‐setting River Styles (10‐90% of the channel margin abuts the valley margin) River Style (Macleay River) Procedure Example of a River Styles tree Partly-confined valley setting Partly-confined valley setting (10-90 % of channel abuts valley margin) sinuous or relatively straight spurred or irregular degree of lateral confinement and valley valley valley configuration (straight vs irregular vs sinuous) channel along channel along channel along valley margin valley margin valley margin (10-50%) (10-50%) river planform (50-90%) high sinuosity high sinuosity compound pools, sand sheets, geomorphic units floodplain, riffles, lateral bars, point bars, cutoffs islands, bed material texture benches floodchannels
bedrock-controlled meandering low sinuosity discontinuous planform- planform- floodplain controlled controlled discontinuous discontinuous floodplain floodplain
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Partly‐confined valley with bedrock‐controlled Partly‐confined valley with planform‐controlled discontinuous floodplain River Style discontinuous floodplain River Style (Clarence River) (Oxley River, Tweed catchment)
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Laterally‐unconfined valley‐setting River Styles Partly confined continuum (discontinuous channel)
Example of a River Styles tree Procedure
Laterally-unconfined valley setting Laterally-unconfined valley setting Confined Partly-confined valley setting Laterally unconfined (<10 % of channel abuts no channel/ valley setting valley-setting valley margin) Bedrock-controlled Low sinuosity Meandering discontinuous channel discont. fplain Planform-controlled Planform-controlled discont. fplain discont. fplain absent or present and ponds, swamp, discontinuous continuous channel channel floodout, sand splay, discont. channel geomorphic units river planform Transitions between valley settings mud/sand texture on valley floor Transitions between River Styles valley floor geomorphic units texture chain of ponds, bed material texture intact valley fill, floodout, discontinuous Fryirs & Brierley, 2010 sand bed
Chain‐of‐ponds River Style Floodout River Style (Murrumbateman Creek, Southern Tablelands, NSW) (White Cliffs, Western NSW)
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Laterally-unconfined valley setting
continuous Laterally‐unconfined valley‐ channel up to Intact valley fill River Style setting River Styles 1 channel 3 channels >3 channels
(Frogs Hollow Creek, Bega catchment) low- high moderate-high low-high (continuous channel) moderate sinuosity sinuosity sinuosity sinuosity (<10% of the channel margin abuts mod-high laterally laterally laterally avulsive laterally the valley margin) instability stable active stable stable
cascades, pool-riffle, lateral bars, lateral bars, sand sheets, pools, point pool-riffle, swampy ponds, boulder bars, runs, sand sheets, chute inset features, benches, runs, islands, pools & low pools, islands, lateral bars, benches, levees, channels, swampy low point bars, chute flow stringers, avulsion mid-channel backswamps sand sheets, flow channel cutoffs, palaeo- channels, flat floodplain channels bars, levees floodchannels floodchannels channels, palaeo- backswamps channels gravel/ gravel/ sand/ sand/ sand/ boulders boulders mud mud mud mud gravel mud/sand low low-moderate sinuosity sinuosity low-moderate boulder gravel sinuosity sand low sinuosity channelised meandering wandering fine grained Procedure bed bed bed fine grained fill fine grained gravel bed anabranching
compound sand sheets, multi- Laterally-unconfined valley setting floodplain, point bars, channel (<10 % of channel abuts point bars, benches, belt, flat valley margin) islands, cutoffs, floodplain pool-riffle levees palaeochannels, absent or present and backswamps, discontinuous continuous gravel sand sand channel channel
meandering meandering multi-channel gravel bed sand bed sand belt geomorphic units river planform
valley floor geomorphic units texture bed material texture Example of a River Styles tree (pg 265)
Meandering sand bed River Style Meandering fine grained River Style (British Columbia) (Mann catchment, North Coast NSW)
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Low sinuosity sand bed River Style Wandering gravel bed River Style (Bega River, NSW) (Waiau River, New Zealand)
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Braided River Style Anastomosing River Style (Cooper Creek, central Australia) (Rakaia River, New Zealand)
Anabranching River Style Bedrock anastomosing River Style (Western NSW) (Sabie River, South Africa)
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bedrock floodplain core bar bedrock lateral outcrop bar
Alluvial (laterally‐ Questions?
This image cannot currently be displayed. unconfined) continuum • How would you characterize these rivers? • How do these rivers adjust/behave? • How sensitive to disturbance are these rivers?
Time for something a little different … a rivers quiz! • Boulder bed (fans) • Braided • Wandering • Meandering active (often sand‐bed) • Meandering passive (often fine‐ grained) • Low sinuosity (straight) • Anastomosing
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Gary’s river quiz
Type of river Photograph # Discontinuous watercourse (Chain of Ponds, swamp) Confined valley setting ‐ (bedrock) river Braided river Passive meandering river (fine‐grained) Anastomosing river Braided‐anabranching river Wandering gravel‐bed river Partly‐confined valley with bedrock‐controlled floodplain pockets Active meandering river (sand‐bed) Confined valley setting ‐ gorge
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