The multivariate controls of hydraulic geometry: a causal investigation in terms of boundary shear distribution
rivers. 529 observations in the U.K. and the U.S.A. have been analysed. This study also investigates the effects of channel roughness, channel slope and the sediment composition of the channel perimeter on hydraulic geometry.
Hydrological model of peat-mound form with vertically varying hydraulic conductivity
The form of raised peat mires can be considered to reflect the form of the saturated water mound. Here, the form of the mire is calculated for non-uniform, depth-dependent hydraulic conductivity of the peat deposit. Although requiring more
Variability of bedload transport and channel morphology in a braided river hydraulic model
The objectives of this paper are: 1) to assess variability in bedload transport and channel morphology in a 1:50 hydraulic model of a braided river under replicate runs, where all the controlling variables are held constant; 2) to investigate
Complex confining layers. Architecture and hydraulic properties of Holocene and Late Weichselian deposits in the fluvial Rhine-Meuse delta
and their influence on groundwater flow. This book contains the results of an investigation of the facies distribution, hydraulic properties and groundwater flow in Late Weichselian and Holocene fluvial deposits in the Dutch Rhine-Meuse delta. -(AGD)
The effects of slaking and dispersion on the hydraulic conductivity of clay soils
This paper reports on a method that can be used to measure the hydraulic conductivity (K) of slaked and dispersed soils and to relate K to the degree of dispersion and sodium content of the soil.
Quartz concentration as an index of sediment mixing : hydraulic mine-tailings in the Sierra Nevada, California
Hydraulic gold mining delivered large volumes of sediment to northern California stream channels from 1853 to 1884. Distinctive quartz composition of this sediment allow development of a sediment mixing index for determination of tailings
Mechanical and hydraulic resistance relations in crust-topped soils
soil from the central Nile Delta, and a clay soil from the western region of the Nile Delta. Pertinent physical and chemical soil properties of the two soils were determined. Discussion of the results (mechanical resistance, hydraulic resistance, change
Discussion: hydrological model of peat-mound form with vertically varying hydraulic conductivity by Adrian C. ARMSTRONG and reply
The AA. argue that the premise on which the peat mound model developed by Armstrong (1995) is based, that hydraulic conductivity shows an exponential decline with depth in bog peats, is unsound. Empirical evidence in the literature
Open system, or more correctly, hydraulic pingos, are genetically poorly understood. A continuing problem concerns their need for a perennial groundwater supply (intra- or sub-permafrost). This has to be maintained despite the existence
of continuous permafrost in many areas where they are located. Recent work on Disko Iland has suggested a new type of hydraulic pingo developing only in a marsh environment. It is argued that the marsh setting is not relevant to the formation of these features
The aim of this paper is to analyse hydraulic patterns in a natural pool-riffle sequence with a view to explaining the maintenance of pool-riffle morphology. Recent investigations have stressed the importance of combinations of hydraulic
and sedimentological process interaction. Whilst recognizing that theories based on spatial patterns in sedimentological structure exist, this paper will concentrate on hydraulic rather than sedimentological explanations.
Effects of rock fragment size and cover on overland flow hydraulics, local turbulence and sediment yield on an erodible soil surface
The interactions between overland flow hydraulics and sediment yield were studied in flume experiments on erodible soil surfaces covered by rock fragments. The high erodibility of a non-cohesive fine sediment permitted the effects of local
turbulence and scour on sediment yield to be examined. Overland flow hydraulics and sediment yield were compared for experiments with pebble and cobble rock fragment covers. An adjustment of existing scour formulas that predict scour around bridge piers
Hydraulic and geomorphological effects of run-of-river dams
Channel geometry ; Dam ; Fluvial erosion ; Hydraulic works ; Impact ; Sediment transport ; Stream ; Stream flow
related to the influence of run-of-river dams on the hydraulics and geomorphology of rivers and suggests types of studies that need to be undertaken to address gaps in current knowledge : numerical modeling and experimental investigations to determine
Simulation of wetland water-level manipulation using coupled hydrological/hydraulic modeling
This paper describes the use of a coupled hydrological/hydraulic model developed for a lowland wet grassland in southeast England to simulate the hydrological impacts of alternative ditch-water level management. The effects of modifying the heights
of the drop-board sluices installed within the ditches were investigated. The influence of alternative ditch-water levels upon the water table was limited due to the low hydraulic conductivity of the clay soil. The results have important implications
Hydraulic and sedimentary controls on the availability and use of Atlantic salmon (Salmo salar) spawning habitat in the River Dee system, north-east Scotland
The hydraulic and sedimentary characteristics of the spawning habitat of Atlantic salmon (Salmon salar) in tributary and mainstem locations in a river system in north-east Scotland are described. Salmon used spawning sites with a relatively wide
range in sediment characteristics. Spawning locations were shown to have similar Froude number, despite different sized streams and species of salmonid. Due to its dimensionless nature and significance in characterising flow hydraulics, the Froude number
Tailings fans and valley-spur cutoffs created by hydraulic mining
Sand and gravel tailings from nineteenth century open-pit hydraulic gold mines formed large alluvial fans at tributary confluences in the northwestern Sierra Nevada, California. In the Bear River watershed, several of these fans were so large
that they blocked main channels for decades. Some channels not only aggraded deeply, but also moved laterally and cut across the inner bends of valley spurs. Now locked in bedrock channels, these valley-spur cutoffs impose local controls on geomorphic, hydraulic
Comparison of hydraulic geometry between sand- and gravel-bed rivers in relation to channel pattern discrimination
A comparison has been made between the hydraulic geometry of sand- and gravel-bed rivers, based on data from alluvial rivers around the world. The results indicate a significant difference in hydraulic geometry. On this basis, some diagrams
Dynamic evolution of the unsaturated hydraulic conductivity of a developing crust
This study reports results of hydraulic parameter measurements at the upper part of a soil profile whose surface is undergoing crust development. The aim of the study is to relate the structural evolution of a surface induced by raindrop impact
and the subsequent dynamic change of the hydraulic conductivity and other parameters related to water transit through the crust and the underlying material. Two soils of different susceptibility to crusting were used in the experiments : a silt loam and a silty clay
Sediment from hydraulic mining detained by Englebright and small dams in the Yuba basin
First, historical geomorphic changes in the watershed are outlined that influence the physical context of the feasibility study. The Yuba watershed is centered in the hydraulic gold-mining region. Second, recent findings of high concentrations
of mercury in sediment and fish tissues in the watershed are briefly reviewed. Third, historic data on 20th century hydraulic mining are presented that document numerous small dams built in the Yuba basin to detain mining sediment. Finally, field measurements
The topographic data source of digital terrain models as a key element in the accuracy of hydraulic flood modelling
The effects of the topographic data source and resolution on the hydraulic modelling of floods were analysed. Seven digital terrain models (DTMs) were generated from three different altimetric sources : a global positioning system (GPS) survey
to the time-cost ratio for each methodology. the hydraulic modelling was carried out on a 2 km reach of the Ted River near Sant Juliá de Ramis near Girona in NE Spain.