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  • Persistent and ancient rivers. Some australian examples
  • Australia ; Cenozoic ; Drainage network ; Geochronology ; Palaeogeography ; Palaeohydrology ; Palaeosurface ; River bed ; Stream
  • Rivers are positive feedback systems and, once established and dominant, tend to maintain and enhance that dominance. Thus, major rivers ought to persist. Rivers, some 60 m.y. old (Eocene), that are extant and have been continuously active since
  • initiation have been identified in Australia. Other rivers of equal or even greater antiquity, but with slightly chekered chronologies, also persist in the landscape, as do the ghosts of others. River of similar antiquity occur in other Gondwana landscapes.
  • 1997
  • Human impact on rivers in Hungary as reflected in changes of channel planform
  • Channel geometry ; Cross section ; Floodplain ; Human impact ; Hungary ; Hydraulic works ; Meander ; River bed ; Stream
  • In the second half of the 19th century, flood control measures radically changed the Hungarian river network. Channel length, slope and planform were all directly affected by regulation and also by subsequent river adjustment. In this paper selected
  • sections of 2 rivers are studied. Sinuosity and shifts and dimension changes of meanders are used to detect river mechanism countering or complying with the impact of human intervention.
  • 1997
  • Shifting river management toward salmon restoration in the Columbia River basin
  • Aquaculture ; Economic impact ; Energy ; Power station ; Resource management ; River basin ; Stream ; United States of America
  • The Columbia River Basin is the site of a conflict over two resources : hydroelectricity and Pacific salmon. Since 1982, the Pacific Northwest Power Planning Council has endeavored to mediate the conflict by implementing a water budget measure
  • 1997
  • River-derived slackwater sediments in caves along Cheat River, West Virginia
  • This paper describes flood-derived sediments found within caves of the Cheat River canyon. The stratigraphy of historical and paleoflood slackwater sediments, sedimentary units within slackwater deposits, and the origins are discussed and compared
  • to surficial slackwater deposits elsewhere along the Cheat River floodplain.
  • 1997
  • A geomorphological approach to the ecological management of rivers in the Kruger National Park : the case of the Sabie River
  • Braided channel ; Channel geometry ; Discharge ; Ecosystem ; Model ; National park ; Regional planning ; River management ; Semi-arid area ; South Africa ; Stream ; Stream flow ; Transvaal ; Water management ; Water resources ; Water use
  • The management of river systems in conservation areas in South Africa is problematic. A framework is developed for predicting changes in river state under different (natural and controlled) flow regimes. The approach involves river classification
  • 1997
  • The water resources in the Euphrates river and the Tigris river valleys and political relation between countries concerned
  • There is a view that owing to the scarcity of the water resources and rapid increase in population in the Middle East and existing of large rivers, the contradictions over the water resources have become increasingly sharp among the countries
  • 1997
  • The influence of waters from hard-coal mines on the hydrochemical relations of Upper Silesian Coal Basin (USCB) rivers
  • Anthropogenic impact on water conditions (Vistula and Oder river basins)
  • This paper is an attempt to estimate the influence of minewater discharge from the hard coal mines of USCB on the shaping of the hydrochemical conditions of river waters, considering mostly salinity and the salt load removed from this area
  • by the Vistula and Oder rivers.
  • 1997
  • Bankfull discharge recurrence interval in gravel-bed rivers
  • Bankfull discharge was identified in some 30 gravel-bed rivers representing in total c. 40 gauging stations. The catchment sizes vary from 4km2 to nearly 2700 km2. Bankfull discharge value increases with basin size. The selected rivers are spread
  • over 5 natural regions which show strong lithological differences. The AA. study the bankfull discharge recurrence interval for rivers flowing on permeable and impermeable terrain.
  • 1997
  • Studies on terraces and river system changes of the upper Yellow River
  • There are 7 steps of terrace both in the Guide basin and Gonghe basin along the Yellow River. 3 ancient terraces are found in the Gonghe basin. The upper reaches of the Yellow River was joined up by a series of stream captures at different periods
  • of time, the ancient Yellow River linked up the Gonghe basin and Guide basin at the end of the middle Pleistocene, the Longyangxia gorge developed around 60 Ka.B.P., and the gorge between Maqu and Tangnag developed around 20 Ka.B.P.
  • 1997
  • High bedrock incision rates in the Atenguillo River valley, Jalisco, western Mexico
  • Lava flows from 3 basaltic shield volcanoes preserve Pliocene-Pleistocene river levels in the Atenguillo River basin. K-Ar dates of these basalt flows, together with present and palaeoriver levels, allow calculation of bedrock incision rates at 3
  • points along the length of the Atenguillo River: Volcan La Laja, Volcan La Cienega, Volcan El Vigia. The high incision rates, as well as 2 distinct knickpoints along the profile of this river are related to a base level change at the northern end
  • of the basin. The dynamics of this river basin are controlled by the ongoing process of continental fragmentation associated with the opening of the Gulf of California.
  • 1997
  • Adjustments in river channel geometry associated with hydraulic discontinuities across the fluvial-tidal transition of a regulated river
  • Carrying capacity ; Channel geometry ; Cross section ; England ; Fluvial hydrology ; Grain size distribution ; River bed ; Sediment transport ; Stream ; Stream flow ; Tide ; United Kingdom ; Wales
  • This paper summarizes existing research results on the hydrogeomorphology of the 18 km reach of the lower River Dee. It describes the preparation and analysis of channel cross-sectional surveys from 122 locations along the reach, and then assesses
  • the process significance of the observed morphological trends. The possible relationship between channel form and process within the study reach is explored by identifying 4 stretches of river that are differently influenced by tides and the tidal weir
  • 1997
  • Evolution of mid-channel bars in a braided river and complex response to reservoir construction : an example from the middle Hanjiang River, China
  • Using the middle Hanjiang River as an example, this paper deals with the development of mid-channel bars in a braided river, as controlled by channel boundary conditions, runoff and sediment load, as well as reservoir construction. Relations have
  • 1997
  • Quantitative determination of the activity of within-reach sediment storage in a small gravel-bed river using transit time and response time
  • Carrying capacity ; Channel geometry ; Grain size distribution ; Gravel ; Methodology ; Quantitative analysis ; River bed ; Scotland ; Sediment load ; Storage site ; Stream ; Tracer ; United Kingdom
  • This paper demonstrates how fractional sediment storage activity in a gravel-bed river can be quantified using a within-reach sediment budget and reservoir theory. Deployment of magnetic tracer particles allows accurate characterisation of sediment
  • fluxes in gravel-bed rivers and provide the opportunity to quantify storage activity using reservoir theory. The results suggest that transit time is difficult to determine from tracer studies in gravel-bed rivers. Consequently, a refinement of transit
  • 1997
  • Geomorphic responses of lower Bega River to catchment disturbance, 1851-1926
  • Australia ; Channel geometry ; Deforestation ; Flood ; Floodplain ; Fluvial processes ; Human impact ; Land use ; New South Wales ; River bed ; Sedimentation ; Stream ; Vegetation degradation
  • Prior to significant European settlement of the area in the 1850s, lower Bega River on the South Coast of NSW had a narrow, relatively deep channel lined by river oaks. By 1926 the channel had widened extensively (up to 340%) and shallowed
  • on the morphology and behaviour of Bega River.
  • 1997
  • Study of sedimentation zones in a large sand-bed braided river : an example from the Hanjiang River of China
  • The concept of sedimentation zone is applied to the study of spatial and temporal variations of mid-channel bars in the middle Hanjiang River, a large sand-bed braided river in China. A sytematic comparison between sedimentation and transport zones
  • 1997
  • Suspended sediment in the river Rhine. The impact of climatic change on erosion, transport, and deposition
  • The aim of this study was to assess the impact of climatic change on sediment transport in the river Rhine, and on the deposition of suspended sediment on the embanked floodplains in the Netherlands. - (AGD)
  • 1997
  • Changes in the chemism of the waters of the Łabuńka river catchment under the influence of municipal and industrial wastewater
  • Anthropogenic impact on water conditions (Vistula and Oder river basins)
  • In the years 1989-1992, river water samples for physicochemical analyses were taken at 9 points of the Łabuńka river catchment up-stream of the gauging station of the Institute of Meteorology and Water Management (IMWM) in Krzak. These show
  • 1997
  • Anthropogenic changes in the suspended load transportation by and sedimentation rates of the river Vistula, Poland
  • Anthropogenic impact on water conditions (Vistula and Oder river basins)
  • Evidence is presented that regulation works on the Vistula channel have introduced very significant and rapid changes in the magnitude of river load transportation and sedimentation. It is acknowledged that human interference represents the most
  • by and sedimentation rates of others rivers influenced by intensive urbanization.
  • 1997
  • Linking river channel form and process: time, space and causality revisited
  • Alps (The) ; Carrying capacity ; Channel geometry ; Chaos ; Determinism ; Fluvial processes ; Meander ; Model ; River bed ; Stream ; Switzerland ; Turbulence
  • This paper aims to illustrate the implications of one particular case study, in the Swiss Alps, for the understanding of the relationship between river channel form and process, and to raise some of the methodological issues associated with small
  • -scale site-specific research. 3 related themes are considered: the nature of the link between channel form and process revealed by intensive study of a dynamic river system; the significance of the conditional role of channel geomorphology in this link
  • 1997
  • Cosmogenic isotope analyses applied to river longitudinal profile evolution: problems and interpretations
  • Channel geometry ; Dating ; Erosion rate ; Geochemistry ; Hawaii ; Isotope analysis ; Longitudinal section ; River bed ; Stream
  • This paper presents an effort to link a field-based study with surface exposure dating techniques to understand river longitudinal profile evolution. The study was aimed at improving the understanding of the rates and processes governing bedrock
  • channel incision. Samples to be analysed for cosmogenic isotopes were collected along a river profile and both radionuclide and stable nuclide concentrations were measured in the rocks. Specifically the nuclides 10Be, 26Al,36Cl,21Ne and 3He allow direct
  • 1997