inscription
PORTAIL D'INFORMATION GÉOGRAPHIQUE

Résultats de la recherche (181 résultats)

Affinez votre recherche

Par Collection Par Auteur Par Date Par Sujet Par Titre
  • Hydraulic geometry and maximum flow efficiency as products of the principle of least action
  • Carrying capacity ; Channel geometry ; Concept ; Stream ; Stream flow
  • . The theoretical results obtained here demonstrate that maximum flow efficiency (MFE) determines stable alluvial channel geometry and that this is a product of both maximum sediment transporting capacity (MSTC) and minimum stream power (MSP). Furthermore
  • This study finds that by introducing a channel form factor (width/depth ratio), the self-adjusting mechanism of alluvial channels can be illustrated directly with the basic flow relations of continuity, resistance and sediment transport
  • 2000
  • The effect of bedload transport on mean and turbulent flow properties
  • Carrying capacity ; Energy balance ; Experimentation ; Roughness ; Runoff ; Stream ; Stream flow ; Turbulence
  • This paper present the results of a flume experiment that was designed to investigate the effect of bedload transport on mean and turbulent properties of the flow. The data obtained from the experiment show that bedload transport may either cause
  • the flow to decelerate or accelerate , depending on the roughness of the bed, hydraulic conditions, and bedload transport rate. A deeper understanding of the feedback effects of bedload is gained by taking into account the turbulent component of the flow.
  • 2000
  • Interannual and interdecadal variability in stream flow from the Argentine Andes
  • Andes ; Argentina ; Correlation ; El Niño ; Flood ; Interannual variability ; Mountain ; Ocean atmosphere interaction ; Precipitation ; Stream ; Stream flow
  • The associations between mean annual stream flow records from 15 rivers draining the Argentine Andes, ranging from the Altiplano to Patagonia, and the Southern Oscillation Index (SOI) as established through simple lag cross-correlation, are examined
  • 2000
  • On large-scale flow structures in a gravel-bed river
  • Canadian geomorphology 2000
  • Canada ; Carrying capacity ; Experimentation ; Gravel ; Quebec ; River bed ; Runoff ; Stream ; Stream flow ; Turbulence
  • This paper confirms the presence of large-scale flow structures in gravel bed rivers, pictures their sequence and patterns and characterises their mean and individual properties. The analysis relies on a new technique for displaying velocity
  • 2000
  • Modelling vegetation interactions with channel flow in river valleys of the Mediterranean region
  • Channel geometry ; Desertification ; Flood ; Impact ; Mediterranean States ; Model ; Natural hazards ; Semi-arid area ; Simulation ; Stream ; Stream flow ; Vegetation
  • of characteristics and processes in the vegetation component of the model is discussed. The effects of vegetation upon flow, erosion and deposition processes and the feedback of flow, sediment and moisture on vegetation are identified. The conceptualisation
  • 2000
  • Amazonas River ; Exploration ; Peru ; Prague ; Scientific expedition ; Springs ; Stream ; University
  • flows and altitudes in order to create the lenghtwise profile of the Rio Carhuasanta stream. The map of Czech explorer Samuel Fritz from 1707 was presented. - (MS)
  • 2000
  • Colorado ; Fluvial dynamics ; Model ; Mountain ; Roughness ; Stream ; Stream flow ; United States of America
  • that are based on several measurements in the flow column improve with explicit Riemann averaging, versus simple averaging, of the measurements.
  • 2000
  • Arid area ; Carrying capacity ; Field experiment ; Mediterranean area ; Mountain ; Roughness ; Sediment load ; Spain ; Stream ; Stream flow
  • An automatic bedload monitoring station has been established on the perennial Tordera River, a Mediterranean mountain gravel-bed stream located in NE Spain. The AA. present data on channel-average bedload flux for this river and on the response
  • 2000
  • Discharge ; Hydrodynamics ; Runoff ; Stream flow
  • 2000
  • Magnitude of deviatoric terms in vertically averaged flow equations
  • Colorado ; Longitudinal section ; Mathematical hydrology ; Mountain ; River bed ; Roughness ; Slope gradient ; Stream ; Stream flow ; United States of America
  • 2000
  • Arid area ; Australia ; Carrying capacity ; Channel geometry ; Concept ; Flood ; Fluvial hydrology ; Palaeohydrology ; Stream ; Stream flow
  • 2000
  • Braided channel ; Carrying capacity ; Channel geometry ; Discharge ; Gravel ; Model ; New Zealand ; Numerical model ; Sediment load ; South Island ; Stream
  • This paper outlines an approach for estimating the annual bedload yield of a braided channel. This procedure is based on the extension of the theory of flow and sediment transport in braided rivers recently presented by Paola (1996). The potential
  • for using such an approach to quantify the relationship between bedload yield and stream morphology is investigated herein with reference to the Waimakariri River, New Zealand.
  • 2000
  • Channel geometry ; Colorado ; Discharge ; Fluvial hydrology ; Longitudinal section ; Mountain ; River bed ; Stream ; Stream flow ; Turbulence ; United States of America
  • control variables bedform type, reach gradient and flow depth. To test the hypothesis that velocity characteristics are related to channel bedform types, ANOVA and ANCOVA tests were performed. The bed-generated turbulence and skin friction of runs appear
  • 2000
  • Fluvial hydrology ; Hydrodynamics ; Morphometry ; River bed ; Runoff ; Stream flow ; Typology
  • 2000
  • Tufa accumulations in ephemeral streams : observations from the Kimberley, north-west Australia
  • Australia ; Biogenic process ; Evaporation ; Karst ; Runoff ; Sedimentary ; Semi-arid area ; Stream flow ; Tufa ; Western Australia
  • 2000
  • Arid area ; Climatic variability ; Drought ; Flood ; Impact ; National park ; Precipitation ; Riparian vegetation ; Seasonal variation ; Semi-arid area ; South Africa ; Stream ; Water regime
  • Semi-arid rivers are subject to highly variable flow regimes as a result of strongly seasonal and unpredictable rainfall. Riparian landscape state changes resulting from a prolonged low flow period followed by a high magnitude flood were examined
  • in the semi-arid, mixed bedrock / alluvial Sabie River in the Kruger National Park. Flow reductions and increased sediment supply may result in long-term changes. - (AJC)
  • 2000
  • Cher ; Flood ; France ; Human impact ; Hydraulic works ; Hydrosystem ; River bed ; Stream ; Stream flow
  • 2000
  • Applied geomorphology ; Bibliography ; Classification ; River management ; Sediment transport ; Stream ; Stream flow ; Vegetation
  • 2000
  • Fluvial dynamics ; Gravel ; Runoff ; Stream ; Stream flow ; Turbulence
  • 2000
  • Carrying capacity ; Derbyshire ; Discharge ; England ; Flood ; Grain size distribution ; Longitudinal section ; Precipitation ; Sediment load ; Stream ; United Kingdom ; Watershed
  • The analysis focuses on profile form and channel slope along the River Noe and its 6 largest tributaries. The basin is underlain by 3 main lithologies, sandstone, shale and limestone. Channel bed slope is steep in upstream reaches and the streams
  • the coarseness of the load, amounts of sediment transport are likely to be small, even during flood flows.
  • 2000