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  • Channel pattern of proglacial rivers : topographic forcing due to glacier retreat
  • Braided channel ; Channel geometry ; Cold area ; Deglaciation ; Glacier retreat ; Iceland ; Palaeohydrology ; Proglacial features ; River bed ; Stream ; Topography
  • This paper compares widely used models of river channel pattern against the changes observed at Skaftafellsjökull, Iceland. Topography was found to play a large role in determining channel pattern in proglacial environments for 2 reasons : 1
  • ) glacier retreat forces rivers to flow through confined moraine reaches; 2) proximal incision of proglacial rivers, accompanied by downstream aggradation, leads to changes in slope which force the river to cross channel pattern thresholds. The findings
  • of this work indicate that in the short term, the majority of channel pattern change in proglacial rivers is due to topographic forcing, and that changes due to changing hydrology and sediment supply are initially relatively minor, although likely to increase
  • 2014
  • Holocene evolution of meander bends in lowland river valley formed in complex geological conditions (the Obra River, Poland)
  • Ground-penetrating radar surveys, coring and the analyses of satellite and aerial images have been carried out to study differences in the evolution of meander bends formed in various geological conditions, in the lower course of the Obra River
  • (western Poland). Four types of meanders were distinguished : laterally migrating bends characterized by frequent changes of migration direction accompanied by river bed avulsions and cutoffs; bends with traces of continuous migration limited by stagnant
  • water basin deposits; confined meanders in a narrow valley formed in glacial till characterized by the occurrence of mid-channel islands; and meanders with traces of complex changes of the river bed migration influenced by anthropogenic intervention
  • of actively migrating meandering rivers.
  • 2014
  • Evolution characters of water exchange abilities between Dongting Lake and Yangtze River
  • By using field-survey hydrological data of the related control stations in Dongting Lake and the Yangtze River mainstream in 1951–2010, the evolution characters of water exchange abilities between the two water bodies and their response
  • to the operation of the Three Gorges Reservoir (TGR) from different time scales are analyzed based on their hydraulic relations. The results highlight that there is a complex hydrological and hydraulic exchange process between Dongting Lake and Yangtze River under
  • the interaction of the river-lake hydrodynamic force. So there is an in-line growth or decline relation between the river-lake water exchange ability and the river-lake water exchange amount.
  • 2014
  • An assessment of the erosion potential of the fluvial thermal process during ice breakups of the Lena River (Siberia)
  • During the initial stage of ice breakup of the Lena River (Yakutia, Siberia), ice pushes up onto the river banks and produces large accumulations of ice and sediments that protect the islands' heads against the mechanical and thermal effects
  • of the river's flow. This initial stage is relatively short and terminates only a few days after breakup begins. In the second phase of flooding, after the river ice has melted, the island heads become free of ice. Hence, when water levels are high
  • of the banks of the river islands displayed high interannual variation that is attributed to the variability of the duration and timing of the flood season.
  • 2014
  • A test of equilibrium theory and a demonstration of its practical application for predicting the morphodynamics of the Yangtze River
  • Taking the width/depth ratio of a river channel as an independent variable, a variational analysis of basic flow relationships shows that alluvial-channel flow adjusts channel geometry to achieve stationary equilibrium when the condition of maximum
  • flow efficiency (MFE) is satisfied. As a test of the veracity of MFE and to examine if this theory of self-adjusting channel morphodynamics can be practically applied to large river systems, this study examines the degree of correspondence between
  • theoretically determined equilibrium channel geometries and actual measurements along the middle and lower Yangtze River. Using 4 different forms of the Meyer-Peter and Müller bedload relation and relations of flow continuity and resistance the AA. show
  • that the Meyer-Peter and Müller bedload relation modified on the basis of MFE theory predicts channel dimensions most accurately when applied to the middle and lower Yangtze River. This provides convincing evidence supporting MFE equilibrium theory.
  • 2014
  • [b2] Changjiang River Scientific Research Inst., Wuhan, Chine
  • The influence of dilution on downstream channel sedimentation in large rivers : the Yellow River, China
  • Due to the temporal decoupling of water and sediment sources in a large river basin, a flood from a sediment source area with high suspended sediment concentration (SSC) may be diluted by flow from a major runoff source area with low SSC. Here
  • , this dilution effect is considered for 145 flood events from the Yellow River. Two indices (β1 and β2) describing the dilution effect are proposed, based on water and sediment from the clear water source area and the coarse sediment producing area. Regression
  • frequency of hyperconcentrated flows in the lower reaches. The Longyangxia Reservoir for hydro-electric generation has stored huge quantities of clear runoff from the upper Yellow River during high-flow season since 1985, greatly reducing the dilution
  • 2014
  • Medium-term fluvial island evolution in a disturbed gravel-bed river (Piave River, Northeastern Italian Alps)
  • Aerial photography ; Alps (The) ; Flood ; Fluvial dynamics ; Fluvial island ; Gravel ; Human impact ; Italy ; LiDAR ; River bed ; Stream ; Vegetation ; Veneto
  • Plan-form changes of river features since 1960 were analyzed using aerial photographs, and a LiDAR was used to derive the maximum, minimum and mean elevation of island surfaces, and maximum and mean height of their vegetation, in a 30-km-long reach
  • of the gravel-bed Piave River. The results suggest that established islands lie at a higher elevation than building and pioneer islands, and have a thicker layer of fine sediments deposited on their surface after big floods. After the exceptional flood in 1966
  • 2014
  • RS analysis of glaciers change in the Heihe River Basin, Northwest China, during the recent decades
  • This paper studied the glaciers change information using object-oriented information extraction technology in the Heihe River Basin (including Heihe River and Beida River) since 1960s to 2007/2011. 1:50,000 topographic map data, Landsat TM/ETM
  • + remote sensing images and digital elevation model data were used in this research. Compared with other western mountain glaciers, glaciers retreat in the Heihe River Basin has a higher rate. Analysis of the 6 meteorological stations'annual average
  • 2014
  • Risk assessment of metal species in sediments of the river Ganga
  • Benares ; Ecosystem ; Ganges River ; Geochemistry ; Heavy metals ; India ; Pollution ; Risk ; Sedimentology ; Spatial distribution ; Stream ; UttarPradesh
  • The present study deals with the geochemical fractions of nine heavy metals [chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb)] present on the river sediments using sequential
  • extraction process (SEP) and total acid digestion (TAD). This work was conducted on Ganga river sediments at Varanasi. Various sources of the metal pollution in the city include domestic, industrial and agricultural untreated wastewater draining
  • into the river. Geochemical fractions of the metals–pH relation study, using Medusa Hydra chemical equilibrium software, revealed the presence of different species of metals at different pHs.
  • 2014
  • Network concepts to describe channel importance and change in multichannel systems : test results for the Jamuna River, Bangladesh
  • The AA. developed a semi-automatic method to derive a chain-like directional network from images that represent the multi-channel river and to connect individual network elements through time. The Jamuna River was taken as an example with a series
  • the Jamuna with a different network character. Based on the centrality they calculated a weighted braiding index that represents the number of important channels in the network, which is about two in the Jamuna River and which is larger immediately after
  • floods. It is concluded that the network measure centrality provides a novel characterization of river channel networks, highlighting properties and tendencies that have morphological significance.
  • 2014
  • An environmental gradient of vegetative controls upon channel planform in the source region of the Yangtze and Yellow Rivers
  • Alluvial reaches in the source region of the Yangtze River exhibit predominantly braided channel planforms, while equivalent reaches in the source region of the Yellow River have more diverse planform morphologies including anastomosing/braided
  • planforms. A short period above freezing, coincident with recurrent yet pulsed flows in the source region of the Yangtze River, suppress riparian vegetation growth, promoting the development of braided channel morphologies. In contrast, a milder climate
  • , coincident with less variable flows in the source region of the Yellow River, permit the establishment of different forms of riparian vegetation, thereby supporting the development of a wider range of channel planform morphologies.
  • 2014
  • Reconstructing of anastomosing river
  • Intensive hydro technical works were conducted in the middle course of the Obra River (Poland) at the beginning of the nineteenth century. The natural river course (functioning before the major construction works) was transformed into 3 artificial
  • canals. Ground-penetrating radar investigations, ground-truthed with coring and remote sensing surveys, were conducted to reconstruct the course taken by the river prior to the hydro technical works. This work demonstrated that the Obra formerly had
  • an anastomosing planform. Radiocarbon dating indicated that the earliest of the retraced channels were active before 9000 BP. The retraced river system was formed in a proglacial stream valley perpendicularly cut by remains of subglacial tunnels, now partly filled
  • 2014
  • Comparison of the water quality of the surface microlayer and subsurface water in the Guangzhou segment of the Pearl River, China
  • The water quality in the surface microlayer (SML) and subsurface water (SSW) in the Guangzhou segment of Pearl River, a eutrophic urban river section in China, were analyzed. The spatial and temporal dynamics of nutrient concentrations, heavy metals
  • and bacteria were examined from 2 sampling sites in monthly samples throughout 2010. It is highlighted that the Guangzhou segment of the Pearl River suffers serious pollution from nutrients and heavy metals, as well as microbial contamination. The results
  • of the Pearl River was more degraded than in the SSW.
  • 2014
  • Assessing the Landscape Value of Public Works: Validation of the Methods in the Lowlands of the Middle Section of the Tajo River, Spain
  • Infrastructure ; Landscape ; Public works ; Spain ; Stream ; Tajo ; landscape assessment ; public works ; rivers
  • This paper proposes a method of landscape characterisation and assessment of public works associated with fluvial landscapes, which is validated in the middle section of the Tajo River. In this method, a set of criteria is identified that unifies
  • together, these criteria enable us to describe and assess the value of the public works selected for study, in this case helping us to evaluate the sections of the River Tajo analysed in our study area. Accordingly, the value of all the infrastructures
  • associated to a stretch of the river covering several hundred kilometres was determined and after dividing this stretch into sections, they were compared under equivalent conditions to provide a hierarchal ranking.
  • 2014
  • A legacy of absence : Wood removal in US rivers
  • The focus in this paper is on rivers within the continental United States, including Alaska. Removal of natural wood rafts began in the 17th century in the eastern United States and proceeded westward with the movement of European settlers
  • , accelerating during the 19th-century era of steamboats and floating of cut timber. Removal of the natural wood rafts likely forced many rivers from a multi-thread planform with high channel-floodplain connectivity into an alternative stable state of single
  • sedimentation and river complexity, and in causing a fundamental, extensive, and intensive change in forested river corridors throughout the United States.
  • 2014
  • Rhythmic roughness elements and channel morphology of gravel bed rivers
  • The aim of this paper is to analyse data on transverse ribs, step-pools and riffle and pool sequences, measured by the authors on a few rivers in the Italian Alps and the northern Apennines. Open questions about the origin of these bedforms
  • are considered and tested against the data set available. A few equations relating the main geomorphic parameters are obtained. They can be used for river restoration and paleohydrological inference. The jamming factor (ratio between the size of the coarser
  • in order to discriminate the fields of existence of the larger roughness transverse, cyclic elements of gravel bed rivers and to show that transverse ribs, step-pools and riffle and pool sequences are part of a coarse grained bedform continuum.
  • 2014
  • Coastal processes and sedimentary facies in the Zohreh River Delta (Northern Persian Gulf)
  • The Zohreh River delta is developed since the late-Holocene. The AA. aim to determine the coastal sedimentary processes of this delta and to detect the evolutionary trend of the deltaic plain at the northern Persian Gulf, based on field measurements
  • to land use changes and river bank erosion. A key part of this research is presenting the implications of the permanent shoaling trend which is prograding toward the international shipping corridor at the north of the Persian Gulf.
  • 2014
  • [b1] Dept. of River Engineering and Coastal Protection, Soil Conservation and Watershed Management Research Inst., Tehran, Iran, Republique Islamique d'
  • Sediment properties and heavy metal pollution assessment in the river, estuary and lake environments of a fluvial plain, China
  • In this study, some geochemical properties, major elements and trace metals of sediments from a river, an estuary and a lake were researched in the Yangtze River Delta plain—a fluvial plain. The heavy metal contamination levels were evaluated
  • that the metal contaminations are associated with sediment sources which significantly influence the geochemical properties of sediments in the different aquatic environments of the Yangtze River Delta plain.
  • 2014
  • The role of vegetation in the retention of fine sediment and associated metal contaminants in London's rivers
  • This paper investigates sediment properties at 4 sites across 3 rivers within Greater London to assess the degree to which contaminated sediments are being retained. Within paired restored and unrestored reaches at each site, 4 different bed
  • conditions associated with river restoration may lead to enhanced retention of contaminated fine sediments, particularly around emergent plants, frequently leading to the development of submerged and emergent landforms and potential river channel adjustments.
  • 2014
  • Sediment variability and transport in the littoral area of the abandoned Yellow River Delta, northern Jiangsu
  • The data of surface sediment samples obtained in the littoral area of the Yellow River Delta in 2006 and 2012 are used to study the sediment variability and sediment transport trends by using the geostatistics analysis tool and the grain size trend
  • that not at a sampling station) is used to improve accuracy of data selection. The results show that sedimentary spatial correlation in Lianyun Port area and southern part of the abandoned Yellow River Delta (AS) is better than that in the northern part of the abandoned
  • Yellow River Delta (AN). Sediment transport trends agree with the hydrodynamic forcing (circulation, tidal current, waves and residual current) and correlate to the nearshore topography evolution (accretion or eosion of coastline) in the study area.
  • 2014