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  • Influence of experimental removal of large woody debris on spatial patterns of three-dimensional flow in a meander bend
  • Channel geometry ; Experimentation ; Meander ; Midwest ; Model ; Stream ; Stream flow ; United States of America
  • This study reports the results of a large woody debris (LWD) removal experiment in a meander bend along a low-energy stream in the Midwestern United States. The results indicate that the LWD obstruction influenced 3D flow structure in this bend
  • at all flow stages. After the removal of LWD from the bend, both downstream and secondary velocities increased and, though still weak, secondary flow intensified.
  • 2007
  • Mesuring streambank erosion due to ground water seepage : correlation to bank pore water pressure, precipitation and stream stage
  • Bank erosion ; Mississippi ; Porosity ; Precipitation ; Soil properties ; Stratigraphy ; Stream ; Underground flow ; United States of America
  • The aim of this research was to demonstrate the importance of streambank composition and stratigraphy in controlling seepage flow and to quantify correlation of seepage flow/erosion with precipitation, stream stage and soil pore water pressure
  • 2007
  • Analysis of the influence of gully erosion in the flow pattern of catchment streams, Southeastern Brazil
  • Brazil ; Gully erosion ; Human impact ; Hydrochemistry ; Hydrological regime ; Minas Gerais ; Precipitation ; Runoff ; Stream flow ; Watershed
  • In order to analyze the influence of erosion in the hydrological behavior of small streams, two similar catchments of the upper portion of the Velhas River were simultaneously monitored throughout a hydrological year. Rainfall, stream flow
  • and hydrochemical data were sytematically collected. The results showed that the eroded catchment presented smaller baseflow rates and bigger but short-lived stormflows. This contrasting flow regime is attributed to the gully, which is causing the partial withdraw
  • 2007
  • Nonlinear determinism in river flow : prediction as a possible indicator
  • Determinism ; Fluvial dynamics ; Forecast ; Methodology ; Runoff ; Stream ; Stream flow
  • This study addresses the issue of nonlinear determinism in river flow series using prediction as a possible indicator. First, a brief account of the nonlinear local approximation method and the inverse approach to identify nonlinear determinism
  • is presented. Next, a review of the studies that have attempted river flow predictions using the nonlinear deterministic method is provided, followed by a discussion on the presence of nonlinear determinism through the inverse approach. Conclusions and scope
  • 2007
  • A case study of the processes displacing flow from the anabranching Ovens River, Victoria, Australia
  • Australia ; Braided channel ; Channel geometry ; Floodplain ; Meander ; Model ; New South Wales ; Shear stress ; Stream
  • The AA.used geomorphic interpretation and hydraulic models embedded in the location-for-time model to determine how flow is displaced on the Ovens River. Meander extension and, to a lesser extent, vertical accretion were found to reduce the energy
  • expended in channels and drive the changes that displace flow onto the floodplain. This displaced flow potentially initiates an avulsion, the scouring of a new channel.
  • 2007
  • Measuring water velocity in highly turbulent flows : field tests of an electromagnetic current meter (ECM) and an acoustic Doppler velocimeter (ADV)
  • Canada ; Comparative study ; Geophysics ; Measurement ; Methodology ; Quebec ; Stream ; Stream flow ; Turbulence
  • Two field tests were completed to compare the performance of an electromagnetic current meter (ECM) with that of an acoustic Doppler velocimeter (ADV) in gravel-bed rivers. Research was particularly motivated by the need to measure flow properties
  • in highly energetic turbulent flows. Measurements were made at 2 field sites, one at moderate velocities and with moderate turbulence intensities, and the other with fast mean velocities and high turbulent intensities. The conclusion is that the older ECM
  • technology provides the more reliable estimates of flow parameters in high turbulence.
  • 2007
  • Channel geometry ; Experimentation ; Longitudinal section ; Roughness ; Runoff ; Statistics ; Stream ; Stream flow
  • conditions are carried out and interpreted by means of a theoretical model. Finally, a criterion is obtained to estimate flow resistance developed by natural step-pool streams when a formative flow discharge occurs based on geometric quantities only.
  • The AA. investigate flow resistance developed by macro-roughness represented by pebbles positioned on a granular layer according to a regularly spaced stripe pattern on steep bed slopes. Flume experiments under various geometrical and hydraulic
  • 2007
  • Scaling the effects of riparian vegetation on cross-sectional characteristics of ephemeral mountain streams - a case study of Nahal Oren, Mt. Carmel, Israel
  • Bank erosion ; Israel ; Mountain ; Riparian vegetation ; Scrub ; Stream ; Stream flow ; Tree ; Vegetation
  • To assess the effect of trees and shrubs on stream structure on different spatial scales, the AA. tested the relationships between their percentage coverage in relation to width, depth and stream slope. This research was conducted during the winter
  • and spring of 2004 at Nahal Oren, Israel, an ephemeral mountainous stream. The AA. suggest that shrubs and trees may have a similar function in stabilizing banks via the root system, but the above-ground structure of these vegetative types has different
  • 2007
  • Factors influencing retention of coarse particulate organic matter in streams
  • Channel geometry ; Land use ; Litter ; New Zealand ; North Island ; Riparian vegetation ; Stream ; Vegetation
  • Input of terrestrial coarse particulate organic matter (CPOM : leaves and small wood,>1 mm) adds food resources and habitat to streams. The AA. investigated retention characteristics under base-flow conditions in 65 stream reaches in pasture, native
  • with results from Spain showed similar relationships between retention distance of plactic CPOM analogues and dicharge under base-flow conditions.
  • 2007
  • Bank erosion ; Experimentation ; Infiltration ; Mississippi ; Model ; Runoff ; Soil properties ; Stream ; United States of America
  • Seepage flow and sediment concentrations were measured in situ at eight locations along the banks of a deeply incised stream in northern Mississippi. Using field observations as a guide, lysimeter experiments were conducted to experimentally
  • simulate the soil and hydrologic conditions in which seepage erosion results in streambank failure of deeply incised streams in which stream stage does not contribute to bank storage or failure.
  • 2007
  • Frequency-magnitude relationships for precipitation, stream flow and sediment load events in a small Mediterranean basin (Vallcebre basin, Eastern Pyrenees)
  • Badland ; Mediterranean climate ; Mountain ; Precipitation ; Pyrénées ; Sediment transfer ; Spain ; Stream flow ; Watershed
  • 2007
  • Structural control on surface flow in karstic environment
  • Aquifer ; Carbonate rock ; Champagne-Ardenne ; Fracture ; France ; Impact ; Karst ; Karstification ; Marne ; Structural geomorphology ; Underground flow ; Watershed
  • Aquifer hydrodynamical properties, hydrogeological tracing, mapping and piezometric monitoring characterised underground flow in calcareous environments. Surface flow study during low-water season showed water supply heterogeneity due to calcareous
  • aquifer anisotropy. It also underlined the role of structure on water transfer and exchanges between aquifers and rivers. By controlling the hydraulic gradient between the streams network and the saturated zone, structure compartmentalisation moderated
  • considerably the role of fracture on undergroud flow. Several examples of calcareous basins from eastern France were studied.
  • 2007
  • Experimentation ; Fluvial erosion ; Roughness ; Sediment transport ; Stream ; Stream flow ; Topography ; Turbulence ; United States of America ; Utah
  • transported as bedload, a single erosion mechanism (abrasion) and sediment-starved transport conditions. They find that patterns of erosion both create and are sensitive functions of the evolving bed topography because of feedbacks between the turbulent flow
  • 2007
  • Contribution of dead wood to the carbon flux in forested streams
  • Carbon ; Ecosystem ; Flow ; Litter ; Model ; Organic materials ; Riparian vegetation ; Spain ; Stream
  • The AA. evaluated the contribution of dead wood to the total carbon flux in 2 headwaters forested streams in northern Spain, one running under mature deciduous forest, the other under eucalyptus plantations. Breakdown rates were measured from
  • branches and compared with the breakdown loss of leaf litter calculated for the same reaches. So, fine dead wood contributes to a significant fraction of the total breakdown of allochtonous organic matter in the studied streams; other sizes of dead wood
  • 2007
  • Effect of bed topography on soil aggregates transport by rill flow
  • The aim of this work is to investigate the ability of the flow to transport soil aggregates along a real rill at discharges below the formative discharge; and to analyse the influence of the rill pools on this transport process. This subject
  • is an important issue as the transport capacity of rills is highly relevant for phenomena such as soil exportation from fields, catchment-scale sediment redistribution, and sedimentation in streams.
  • 2007
  • China ; Flood ; Huang He ; Inundation ; Model ; Scenario ; Simulation ; Stream ; Stream flow
  • area to two-dimensional unsteady flow model. According to the results of different situations, the AA. expect to sum up the characteristics of dike-break flood routing by contrasting the inundated range, depth and maximum flow velocity.
  • 2007
  • Channel geometry ; Colorado ; Longitudinal section ; Roughness ; Stream ; Stream flow ; United States of America
  • 2007
  • Braided channel ; Ecosystem ; Flood ; Floodplain ; Habitat ; Italy ; Mediterranean area ; Northern Italy ; Stream ; Stream flow ; Surface water ; Water regime
  • they measured discharge and vertical hydraulic gradients at multiple locations along the corridor. The results emphasize that even small changes in flow can cause major increases or decreases of ecosystem size, thereby creating a highly dynamic and harsh
  • 2007
  • Climatic index ; Correlation ; Dnieper ; Don ; Oka ; Runoff ; Russia ; Stream flow ; Volga
  • 2007
  • Asian part of Russia ; Buryatiya ; Convection ; Ocean wave ; Seasonal variation ; Stream ; Stream flow ; Water temperature
  • 2007