Modification of Meander Migration by Bank Failures
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Seasonal Flooding Affects Habitat and Landscape Dynamics of a Gravel
Seasonal flooding affects habitat and landscape dynamics of a gravel-bed river floodplain Katelyn P. Driscoll1,2,5 and F. Richard Hauer1,3,4,6 1Systems Ecology Graduate Program, University of Montana, Missoula, Montana 59812 USA 2Rocky Mountain Research Station, Albuquerque, New Mexico 87102 USA 3Flathead Lake Biological Station, University of Montana, Polson, Montana 59806 USA 4Montana Institute on Ecosystems, University of Montana, Missoula, Montana 59812 USA Abstract: Floodplains are comprised of aquatic and terrestrial habitats that are reshaped frequently by hydrologic processes that operate at multiple spatial and temporal scales. It is well established that hydrologic and geomorphic dynamics are the primary drivers of habitat change in river floodplains over extended time periods. However, the effect of fluctuating discharge on floodplain habitat structure during seasonal flooding is less well understood. We collected ultra-high resolution digital multispectral imagery of a gravel-bed river floodplain in western Montana on 6 dates during a typical seasonal flood pulse and used it to quantify changes in habitat abundance and diversity as- sociated with annual flooding. We observed significant changes in areal abundance of many habitat types, such as riffles, runs, shallow shorelines, and overbank flow. However, the relative abundance of some habitats, such as back- waters, springbrooks, pools, and ponds, changed very little. We also examined habitat transition patterns through- out the flood pulse. Few habitat transitions occurred in the main channel, which was dominated by riffle and run habitat. In contrast, in the near-channel, scoured habitats of the floodplain were dominated by cobble bars at low flows but transitioned to isolated flood channels at moderate discharge. -
River Dynamics 101 - Fact Sheet River Management Program Vermont Agency of Natural Resources
River Dynamics 101 - Fact Sheet River Management Program Vermont Agency of Natural Resources Overview In the discussion of river, or fluvial systems, and the strategies that may be used in the management of fluvial systems, it is important to have a basic understanding of the fundamental principals of how river systems work. This fact sheet will illustrate how sediment moves in the river, and the general response of the fluvial system when changes are imposed on or occur in the watershed, river channel, and the sediment supply. The Working River The complex river network that is an integral component of Vermont’s landscape is created as water flows from higher to lower elevations. There is an inherent supply of potential energy in the river systems created by the change in elevation between the beginning and ending points of the river or within any discrete stream reach. This potential energy is expressed in a variety of ways as the river moves through and shapes the landscape, developing a complex fluvial network, with a variety of channel and valley forms and associated aquatic and riparian habitats. Excess energy is dissipated in many ways: contact with vegetation along the banks, in turbulence at steps and riffles in the river profiles, in erosion at meander bends, in irregularities, or roughness of the channel bed and banks, and in sediment, ice and debris transport (Kondolf, 2002). Sediment Production, Transport, and Storage in the Working River Sediment production is influenced by many factors, including soil type, vegetation type and coverage, land use, climate, and weathering/erosion rates. -
2019 Li, Z., Wu, X., and Gao, P.*, Experimental Study on the Process of Neck Cutoff
Geomorphology 327 (2019) 215–229 Contents lists available at ScienceDirect Geomorphology journal homepage: www.elsevier.com/locate/geomorph Experimental study on the process of neck cutoff and channel adjustment in a highly sinuous meander under constant discharges Zhiwei Li a,b, Xinyu Wu a,PengGaoc,⁎ a School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha 410114, China b Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province, Changsha 410114, China c Department of Geography, Syracuse University, Syracuse, NY 13244, USA article info abstract Article history: Neck cutoff is an essential process limiting evolution of meandering rivers, in particular, the highly sinuous ones. Received 29 July 2018 Yet this process is extremely difficult to replicate in laboratory flumes. Here we reproduced this process in a Received in revised form 1 November 2018 laboratory flume by reducing at the 1/2500 scale the current planform of the Qigongling Bend (centerline length Accepted 1 November 2018 13 km, channel width 1.2 km, and neck width 0.55 km) in the middle Yangtze River with geometric similarity. In Available online 07 November 2018 five runs with different constant input discharges, hydraulic parameters (water depth, surface velocity, and slope), bank line changes, and riverbed topography were measured by flow meter and point gauges; and bank Keywords: fl Meandering channel line migration and a neck cutoff process were captured by six overhead cameras mounted atop the ume. By Neck cutoff -
Preprint 06-041
SME Annual Meeting Mar. 27-Mar.29, 2006, St. Louis, MO Preprint 06-041 A MEANDER CUTOFF INTO A GRAVEL EXTRACTION POND, CLACKAMAS RIVER, OREGON P. J. Wampler, Grand Valley State Univ., Allendale, MI E. F. Schnitzer, Dept. of Geology and Mineral Industries, Albany, OR D. Cramer, Portland General Electric, Estacada, OR C. Lidstone, Lidstone and Assoc(s)., Fort Collins, CO Abstract Introduction The River Island mining site is located at approximately river mile The River Island site provides a unique opportunity to examine (RM) 15 on the Clackamas River, a large gravel-bed river in northwest the physical changes to a river channel resulting from avulsion into a Oregon. During major flooding in February 1996, rapid channel gravel extraction pond. Data from before and after the meander cutoff change occurred. The natural process of meander cutoff, slowed for allow evaluation of changes to river geometry, sediment transport, several years by dike construction, was accelerated by erosion into temperature, habitat, and channel form. gravel extraction ponds on the inside of a meander bend during the An avulsion is defined as a lateral migration or cutoff of a river. It flood. involves the diversion of water from the primary channel into a new In a matter of hours, the river cut off a meander and began flowing channel that is either created during the event or reoccupied. through a series of gravel pits located on the inside of the meander Avulsions may be rapid or take many years to complete (Slingerland bend. The cutoff resulted in a reduction in reach length of and Smith, 2004). -
The Biology and Management of the River Dee
THEBIOLOGY AND MANAGEMENT OFTHE RIVERDEE INSTITUTEofTERRESTRIAL ECOLOGY NATURALENVIRONMENT RESEARCH COUNCIL á Natural Environment Research Council INSTITUTE OF TERRESTRIAL ECOLOGY The biology and management of the River Dee Edited by DAVID JENKINS Banchory Research Station Hill of Brathens, Glassel BANCHORY Kincardineshire 2 Printed in Great Britain by The Lavenham Press Ltd, Lavenham, Suffolk NERC Copyright 1985 Published in 1985 by Institute of Terrestrial Ecology Administrative Headquarters Monks Wood Experimental Station Abbots Ripton HUNTINGDON PE17 2LS BRITISH LIBRARY CATALOGUING-IN-PUBLICATIONDATA The biology and management of the River Dee.—(ITE symposium, ISSN 0263-8614; no. 14) 1. Stream ecology—Scotland—Dee River 2. Dee, River (Grampian) I. Jenkins, D. (David), 1926– II. Institute of Terrestrial Ecology Ill. Series 574.526323'094124 OH141 ISBN 0 904282 88 0 COVER ILLUSTRATION River Dee west from Invercauld, with the high corries and plateau of 1196 m (3924 ft) Beinn a'Bhuird in the background marking the watershed boundary (Photograph N Picozzi) The centre pages illustrate part of Grampian Region showing the water shed of the River Dee. Acknowledgements All the papers were typed by Mrs L M Burnett and Mrs E J P Allen, ITE Banchory. Considerable help during the symposium was received from Dr N G Bayfield, Mr J W H Conroy and Mr A D Littlejohn. Mrs L M Burnett and Mrs J Jenkins helped with the organization of the symposium. Mrs J King checked all the references and Mrs P A Ward helped with the final editing and proof reading. The photographs were selected by Mr N Picozzi. The symposium was planned by a steering committee composed of Dr D Jenkins (ITE), Dr P S Maitland (ITE), Mr W M Shearer (DAES) and Mr J A Forster (NCC). -
New Developments in River Valley Floodplain Mapping Using Dems
New Developments in River Valley Floodplain Mapping Using DEMs: A Survey of FLDPLN Model Applications Jude Kastens | Kevin Dobbs | Steve Egbert Kansas Biological Survey ASWM/NFFA Webinar | January 13, 2014 Kansas Applied Remote Sensing Kansas River Valley between Manhattan and Topeka Email: [email protected] Terrain Processing: DEM (Digital Elevation Model) This DEM was created using LiDAR data. Shown is a portion of the river valley for Mud Creek in Jefferson County, Kansas. Unfilled DEM (shown in shaded relief) 2 Terrain Processing: Filled (depressionless) DEM This DEM was created using LiDAR data. Shown is a portion of the river valley for Mud Creek in Jefferson County, Kansas. Filled DEM (shown in shaded relief) 3 Terrain Processing: Flow Direction Each pixel is colored based on its flow direction. Navigating by flow direction, every pixel has a single exit path out of the image. Flow direction map (gradient direction approximation) 4 Terrain Processing: Flow Direction Each pixel is colored based on its flow direction. Navigating by flow direction, every pixel has a single exit path out of the image. Flow direction map (gradient direction approximation) 5 Terrain Processing: Flow Accumulation The flow direction map is used to compute flow accumulation. flow accumulation = catchment size = the number of exit paths that a pixel belongs to Flow accumulation map (streamline identification) 6 Terrain Processing: Stream Delineation Using pixels with a flow accumulation value >106 pixels, the Mud Creek streamline is identified (shown in blue). “Synthetic Stream Network” 7 Terrain Processing: Floodplain Mapping The 10-m floodplain was computed for Mud Creek using the FLDPLN model. -
Cumulative Effective Stream Power and Bank Erosion on the Sacramento River, California, Usa1
JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION AUGUST AMERICAN WATER RESOURCES ASSOCIATION 2006 CUMULATIVE EFFECTIVE STREAM POWER AND BANK EROSION ON THE SACRAMENTO RIVER, CALIFORNIA, USA1 Eric W. Larsen, Alexander K. Fremier, and Steven E. Greco2 ABSTRACT: Bank erosion along a river channel determines the INTRODUCTION pattern of channel migration. Lateral channel migration in large alluvial rivers creates new floodplain land that is essential for Natural rivers and their surrounding areas consti- riparian vegetation to get established. Migration also erodes tute some of the world’s most diverse, dynamic, and existing riparian, agricultural, and urban lands, sometimes complex terrestrial ecosystems (Naiman et al., 1993). damaging human infrastructure (e.g., scouring bridge founda- Land deposition on the inside bank of a curved river tions and endangering pumping facilities) in the process. channel is a process that creates opportunities for Understanding what controls the rate of bank erosion and asso- vegetation to colonize the riparian corridor (Hupp and ciated point bar deposition is necessary to manage large allu- Osterkamp, 1996; Mahoney and Rood, 1998). Point vial rivers effectively. In this study, bank erosion was bar deposition and outside bank erosion are tightly proportionally related to the magnitude of stream power. Linear coupled. These physical processes (which constitute regressions were used to correlate the cumulative stream channel migration) maintain ecosystem heterogeneity power, above a lower flow threshold, with rates of bank erosion in floodplains over space and time (Malanson, 1993). at 13 sites on the middle Sacramento River in California. Two Channel migration structures and sustains riparian forms of data were used: aerial photography and field data. -
Floodplain Geomorphic Processes and Environmental Impacts of Human Alteration Along Coastal Plain Rivers, Usa
WETLANDS, Vol. 29, No. 2, June 2009, pp. 413–429 ’ 2009, The Society of Wetland Scientists FLOODPLAIN GEOMORPHIC PROCESSES AND ENVIRONMENTAL IMPACTS OF HUMAN ALTERATION ALONG COASTAL PLAIN RIVERS, USA Cliff R. Hupp1, Aaron R. Pierce2, and Gregory B. Noe1 1U.S. Geological Survey 430 National Center, Reston, Virginia, USA 20192 E-mail: [email protected] 2Department of Biological Sciences, Nicholls State University Thibodaux, Louisiana, USA 70310 Abstract: Human alterations along stream channels and within catchments have affected fluvial geomorphic processes worldwide. Typically these alterations reduce the ecosystem services that functioning floodplains provide; in this paper we are concerned with the sediment and associated material trapping service. Similarly, these alterations may negatively impact the natural ecology of floodplains through reductions in suitable habitats, biodiversity, and nutrient cycling. Dams, stream channelization, and levee/canal construction are common human alterations along Coastal Plain fluvial systems. We use three case studies to illustrate these alterations and their impacts on floodplain geomorphic and ecological processes. They include: 1) dams along the lower Roanoke River, North Carolina, 2) stream channelization in west Tennessee, and 3) multiple impacts including canal and artificial levee construction in the central Atchafalaya Basin, Louisiana. Human alterations typically shift affected streams away from natural dynamic equilibrium where net sediment deposition is, approximately, in balance with net -
Defining the Moment of Erosion
Earth Surface Processes and Landforms EarthDefining Surf. the Process. moment Landforms of erosion 30, 1597–1615 (2005) 1597 Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/esp.1234 Defining the moment of erosion: the principle of thermal consonance timing D. M. Lawler* School of Geography, Earth and Environmental Sciences, The University of Birmingham, Birmingham B15 2TT, UK *Correspondence to: Abstract D. M. Lawler, School of Geography, Earth and Geomorphological process research demands quantitative information on erosion and deposi- Environmental Sciences, tion event timing and magnitude, in relation to fluctuations in the suspected driving forces. University of Birmingham, This paper establishes a new measurement principle – thermal consonance timing (TCT) Birmingham B15 2TT. – which delivers clearer, more continuous and quantitative information on erosion and E-mail: [email protected] deposition event magnitude, timing and frequency, to assist understanding of the controlling mechanisms. TCT is based on monitoring the switch from characteristically strong tempera- ture gradients in sediment, to weaker gradients in air or water, which reveals the moment of erosion. The paper (1) derives the TCT principle from soil micrometeorological theory; (2) illustrates initial concept operationalization for field and laboratory use; (3) presents experimental data for simple soil erosion simulations; and (4) discusses initial application of TCT and perifluvial micrometeorology principles in the delivery of timing solutions for two bank erosion events on the River Wharfe, UK, in relation to the hydrograph. River bank thermal regimes respond, as soil temperature and energy balance theory pre- dicts, with strong horizontal thermal gradients (often >>>1Kcm−−−1 over 6·8 cm). -
Classifying Rivers - Three Stages of River Development
Classifying Rivers - Three Stages of River Development River Characteristics - Sediment Transport - River Velocity - Terminology The illustrations below represent the 3 general classifications into which rivers are placed according to specific characteristics. These categories are: Youthful, Mature and Old Age. A Rejuvenated River, one with a gradient that is raised by the earth's movement, can be an old age river that returns to a Youthful State, and which repeats the cycle of stages once again. A brief overview of each stage of river development begins after the images. A list of pertinent vocabulary appears at the bottom of this document. You may wish to consult it so that you will be aware of terminology used in the descriptive text that follows. Characteristics found in the 3 Stages of River Development: L. Immoor 2006 Geoteach.com 1 Youthful River: Perhaps the most dynamic of all rivers is a Youthful River. Rafters seeking an exciting ride will surely gravitate towards a young river for their recreational thrills. Characteristically youthful rivers are found at higher elevations, in mountainous areas, where the slope of the land is steeper. Water that flows over such a landscape will flow very fast. Youthful rivers can be a tributary of a larger and older river, hundreds of miles away and, in fact, they may be close to the headwaters (the beginning) of that larger river. Upon observation of a Youthful River, here is what one might see: 1. The river flowing down a steep gradient (slope). 2. The channel is deeper than it is wide and V-shaped due to downcutting rather than lateral (side-to-side) erosion. -
Floodplain Heterogeneity and Meander Migration
River, Coastal and Estuarine Morphodynamics: RCEM2011 © 2011 Floodplain heterogeneity and meander migration MOTTA Davide Department of Civil and Environmental Engineering University of Illinois at Urbana-Champaign, Urbana, Illinois, USA E-mail: [email protected] ABAD Jorge D. Department of Civil and Environmental Engineering University of Pittsburgh, Pittsburgh, Pennsylvania, USA E-mail: [email protected] LANGENDOEN Eddy J. US Department of Agriculture, Agricultural Research Service National Sedimentation Laboratory, Oxford, Mississippi, USA E-mail: [email protected] GARCIA Marcelo H. Department of Civil and Environmental Engineering University of Illinois at Urbana-Champaign, Urbana, Illinois, USA E-mail: [email protected] ABSTRACT: The impact of horizontal heterogeneity of floodplain soils on rates and patterns of meander migration is analyzed with a Ikeda et al. (1981)-type model for hydrodynamics and bed morphodynamics, coupled with a physically-based bank erosion model according to the approach developed by Motta et al. (2011). We assume that rates of migration are determined by the resistance to hydraulic erosion of the soils, which is described by an excess shear stress relation. This relation uses two parameters characterizing the resistance to erosion: critical shear stress and erodibility coefficient. The spatial distribution of critical shear stress in the floodplain is generated on a regular grid with varying degree of randomness to mimic natural settings and the corresponding erodibility coefficient is computed with a relation derived from field-measured pairs of critical shear stress and erodibility. Centerline migration and associated statistics for randomly-disturbed distribution based on the distance from the valley axis are compared for sine-generated centerline using the Monte Carlo method. -
Sediment-Triggered Meander Deformation in the Amazon Basin
Sediment-triggered meander deformation in the Amazon Basin Joshua Ahmed, José A. Constantine & Thomas Dunne 1 Jose A. Constantine, Thomas Dunne, Carl Legleiter & Eli D. Lazarus Sediment and long-term channel and floodplain evolution across the Amazon Basin 2 Meandering rivers & their importance 3 Controls on meander migration • Curvature • Discharge • Floodplain composition • Vegetation • Sediment? 4 Alluvial sediment • The substrate transported through our river systems • The substrate that builds numerous bedforms, the bedforms that create habitats, the same material that creates the floodplains on which we build and extract our resources. Yet there is supposedly no real connection between this and channel morphodynamics? 5 6 7 Study site: Amazon Basin 8 9 What we did • methods 10 Results 11 Results 12 Results 13 Results 14 Results 15 Proposed mechanisms 16 Summary • Rivers with high sediment supplies migrate more and generate more cutoffs • Greater populations of oxbow lakes (created by cutoffs) mean larger voids in the floodplain • Greater numbers of voids mean more potential sediment accommodation space (to be occupied by fines) • DAMS – connectivity • Rich diversity of habitats 17 36,139 ha Dam, Maderia Finer and Olexy, 2015, New dams on the Maderia River 18 For further information 19 For more information Ahmed et al. In prep i.e., coming soon… to a journal near you 20 References • Constantine, J. A. and T. Dunne (2008). "Meander cutoff and the controls on the production of oxbow lakes." Geology 36(1): 23-26. • Dietrich, W. E., et al. (1979). "Flow and Sediment Transport in a Sand Bedded Meander." The Journal of Geology 87(3): 305-315.