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  • Some thermodynamic criteria for river channel changes
  • Fluvial dynamics ; Geosystem ; River bed ; Spatial variation ; Stream ; Stream flow
  • A theoretical model of river channel changes is presented, which shows some nonequilibrium thermodynamic criteria of a river channel to bedding and equilibrium.
  • 1998
  • Anastomosing rivers. Forms, processes and sediments
  • Tha anastomosing rivers represent a major group of rivers that are currently of interest in fluvial geomorphology and sedimentology. The term is reserved for a type of multichannel river on alluvial plains that most often seems to form under
  • relatively low-energetic conditions. The objects of this study are (1) to develop a consistent definition, (2) to develop a universally applicable conceptual model for the genesis of anastomosing river systems and (3) to document the variability in facies
  • and fluvial architecture of modern and subrecent anastomosing river systems to improve the interpretation of the fossil record. The approach followed is that of comparatice reserch of modern and subrecent anastomosing river systems in various climatic
  • 1998
  • Distribution of large woody debris along the outer bend of meanders in the Ain River, France
  • The distribution of large woody debris (LWD) was studied along the concave outer bend of 3 meanders in the Ain River. The Ain River is a sixth-order channel dominated by a gravel-cobble bed substrate that meanders through a floodplain covered
  • largely by riparian forest vegetation. The total LWD deposited along concavities was most strongly controlled by meander-bend geometry. Findings from this study are applicable to restore alluvial forests along French rivers.
  • 1998
  • River response to Quaternary subsidence due to evaporite solution (Gállego River, Ebro Basin, Spain)
  • In this paper, a model for the long-term river response to subsidence is proposed from the analysis of the geomorphology, sedimentology, magnetostratigraphy and geophysics of the Gállego alluvial deposits. The aim is to provide a better
  • 1998
  • Environmental consequences of human activity on the Yellow River and its delta, China
  • The Yellow River is unique among the major rivers of the world because of its extremely heavy sediment load in relation to its small discharge. The Yellow River has changed courses numerous times during the past 5000 to 6000 years. The abandoned
  • deltas are eroding, whereas the present delta being formed in Bohai Bay is growing rapidly. Human activity, including extensive agriculture, heavy water consumption, the use of river-control structures, and war, has been responsible for many
  • of the changes occurring in the Yellow River and its delta.
  • 1998
  • Geomorphological problems of the middle reaches of the Tsangpo River, Tibet
  • Asia ; Braided channel ; Channel geometry ; Fault ; Fluvial terrace ; Geological structure ; Lithology ; River bed ; Stream ; Tectonics ; Tibet
  • The middle reaches of the Tsangpo River consist of alternating sections of wide valleys and gorges. The wide valley sections have braided and anastomosing channels, gentle hydraulic gradients, thick alluvial deposits and low terraces. In contrast
  • , the gorge sections exhibit single, straight and deeply entrenched meandering channels with steep hydraulic gradients, bare rock river beds and higher terraces. Several hypotheses have been used to explain these unusual fluvial landforms, but geological
  • , landform and sedimentary analyses along with dating information, suggest that the key could be the active faults across the river valley.
  • 1998
  • Late Holocene soil formation in the valley of the River Yenisei, Central Siberia
  • Alluvial sod soil sequences from the 9 m terrace in the valley of the River Yenisei were used to reconstruct the paleoecological history and the paleohydrological regime of the river. This paper describes the alluvial soils and establishes
  • 1998
  • Evolution of cutoffs across meander necks in Powder River, Montana, USA
  • This paper describes a specific mechanism for the formation of chute cutoffs : headcuts that form during floods in the down-river edges of meander necks and progress headward (up-river) across the necks eventually to complete the cutoffs
  • 1998
  • Seasonal hydroclimate change in the Sacramento River Basin, California
  • Reconstructed or unimpaired discharges for 1921 to 1994 for the Sacramento River are employed as an indicator of natural discharge and are analyzed for evidence of seasonal change with 2 questions : 1) are seasonal hydroclimate changes evident
  • in Sacramento River Basin unimpaired discharges? 2) if changes are evident, when did the change in unimpaired discharges first appear?
  • 1998
  • Overbank sand deposition in relation to transport volumes during large-magnitude floods in the Dutch sand-bed Rhine river system
  • Carrying capacity ; Flood ; Floodplain ; Fluvial dynamics ; Fluvial processes ; Netherlands (The) ; Rhine ; River bed ; Sediment transport ; Spatial variation ; Stream
  • Using aerial photographs and field measurements, sandy overbank deposits formed by the large-magnitude floods of 1993/94 and 1995 were quantified along 2 branches of the Dutch Rhine river system : the Waal and the Ijssel. The spatial variability
  • for understanding the dynamics of river floodplain strongly influenced by man.
  • 1998
  • The evolution of the great river systems of southern Asia during the Cenozoic India-Asia collision : rivers draining southwards
  • This paper describes the southward-draining systems of Afghanistan, of Tibet and southeast Asia, and of the Himalaya and southern Tibet, and concentrates on base levels of erosion, recent river gradients and the response to tectonic, climatic
  • 1998
  • The evolution of the modern Luanhe River delta, north China
  • In 1915, the Luanhe River changed course to its present position, and has since developed a typical fan-shaped delta under fluvial-wave interaction. Owing to the water conservancy projects constructed in the catchment, the sand load that the Luanhe
  • River takes into the sea has decreased sharply since 1980. Hence, the evolution of the Luanhe River Delta can be divided into two phases : the delta constructing phase between 1915 and 1979, and the para-abandoned phase after 1979. In the different
  • 1998
  • Suspended sediment yield from the Ansager Å river basin, Denmark
  • The aim of this investigation is to derive a long-term record of suspended sediment yield for the river Ansager Å, for the period from 1969 to 1993, using all the available data. Changes in the methodology used over the period are considered
  • 1998
  • The hydrological regime of rivers in the light of scenarios of global climatic change
  • This article seeks to achieve 2 aims : - to classify the hydrological regimes of the rivers Rega, Utrata and Soła, representing different climatic and physio-geographical regions of Poland, and - to assess changes in their regimes following
  • 1998
  • Spatial variability of soil properties at different scales within three terraces of the Henares River (Spain)
  • This paper shows results obtained from the geostatistical analysis of soil properties within the terraces generated by Quaternary evolution of the Henares River incision. Stationarity is assumed provided the similar nature, origin of the parent
  • 1998
  • Patterns and processes of sediment sorting in gravel-bed rivers
  • After a brief description of the principal sedimentological features of gravel-bed rivers, this article reviews the mechanisms that sort bed material by size during sediment entrainment, transport and deposition and discusses some of the inter
  • 1998
  • Types of river channel patterns and their natural controls
  • River channel patterns are thought to form a morphological continuum. This continuum is two-dimensional, defined by plan features of which there are three (straight, meandering, branching), and structural levels of fluvial relief of which
  • 1998
  • A flood climatology of the lower Roanoke River Basin in North Carolina
  • In this study, a flood climatology of the regulated lower Roanoke River in North Carolina is developed with an explicit focus on the identification of trends in flooding contributed by : 1) climate change and 2) flow regulation from upstream dams
  • 1998
  • Coarse bedload transport in a mountain river
  • transport events associated with the daily rise and fall in stream discharge were investigated. This paper reports the results of this study designed to describe fully the adjustment of river bed and turbulent flow to the unsteady passage of a pebble bedload.
  • 1998
  • The spatial variability of overbank sedimentation on river floodplains
  • The study reported uses Cs 137 measurements on sediment cores to investigate the spatial variability of sediment deposition on selected floodplain reaches of five British lowland rivers. Attention is given both to the overall reach and to more
  • 1998