Lake-sediment-based evaluation of recent sediment yield from a small appalachian watershed, Thompson lake, Virginia
Bassin-versant ; Bilan sédimentaire ; Etats-Unis ; Lac ; Ouragan ; Précipitation ; Susceptibilité magnétique ; Sédiment lacustre ; Sédimentologie ; Utilisation du sol ; Variation spatiale ; Virginia
Hurricane ; Lacustrine sediment ; Lake ; Land use ; Magnetic susceptibility ; Precipitation ; Sediment budget ; Sedimentology ; Spatial variation ; United States of America ; Virginia ; Watershed
In this study, sediments from Thompson Lake, Virginia, are used to study the last 30 years of sediment yield from the 3.8 km2 contributing catchment. Sediment yield changes at this site are found to be related primarily to precipitation history
. This result as well as an established relationship between sediment magnetism and particle size allow for a simple evaluation of sediment yield frequency and magnitude. Two magnetic susceptibility peaks identified in the sediment record are hypothesized
to represent discrete flood sediment strata, one resulting from hurricane Agnes in 1972.
Measurement of reservoir sedimentation in Erosion and sediment yield : some methods of measurement and modelling.
Erosion des sols ; Expérimentation ; Géographie physique ; Mesure ; Réservoir ; Sédimentation ; Technique de recherche
Description d'une méthode évitant les écueils d'une mesure de sédimentation en réservoir et d'une procédure de détermination de l'apport sédimentaire d'un bassin-versant (équipement, précautions, méthodes informatiques, analyses d'échantillons...).
Nouvelle technique d'échantillonnage des sédiments meubles lacustres basée sur le principe de congélation rapide de la carotte in situ afin de préserver sa microstratigraphie et de faciliter l'analyse à intervalles rapprochés.
Sediment yield mapping using small dam sedimentation surveys, Southern Tabelands, New South Wales
Aménagement hydraulique ; Australie ; Barrage-réservoir ; Bassin-versant ; Cartographie thématique ; Erosion des sols ; New South Wales ; Qualité de l'eau ; Sédimentation ; Taux de sédimentation ; Utilisation du sol
Australia ; Catchment area;Watershed ; Dam ; Hydraulic works ; Land use ; New South Wales ; Sedimentation ; Sedimentation rate ; Soil erosion ; Thematic mapping;Thematic cartography ; Water quality
Using an empirical sediment yield equation derived from sedimentation surveys of fourteen small reservoirs, the sediment yields of subcatchments of an adjacent drainage basin were mapped. The results are consistent with geomorphic processes
and with documented effects on sediment yields of land use intensification.
Fluvial sediment budgets in the North Carolina Piedmont
Catchment area;Watershed ; Fluvial processes ; North Carolina ; Pollution ; Sediment budget ; Soil erosion ; United States
The purpose of this study is to estimate and examine rudimentary sediments budgets for four river basins in the Piedmont physiographic province of North Carolina to determine the relative magnitude and importance of sediment storage.
The utility of the sediment budget concept in sediment pollution control
Bilan sédimentaire ; Conservation des sols ; Erosion des sols ; Etats-Unis ; Fluviatile ; Géographie de l'Amérique ; North Carolina ; Pollution ; Qualité de l'eau ; Sédimentation ; Tar River
Les études des sédiments en suspension dans le bassin d'Ystwyth (Centre du Pays de Galles) suggèrent deux méthodes pour identifier leur origine. La couleur des sédiments et les relations sédiments-débits permettent de distinguer les sédiments
originaires du chenal d'écoulement et les sédiments provenant de l'extérieur du chenal.
L'épaisseur des sédiments et les taux de sédimentation au cours de la progression du delta peuvent être prédits à l'aide d'un modèle mathématique. Lorsque la progression est uniforme et que les caractéristiques fluviatiles sont semblables à celles
du nord du Golfe du Mexique le modèle prédit une augmentation du taux de sédimentation en un point fixé, tant que la sédimentation sur la pente deltaïque continue.
Sediment yield and sediment retention in a small loess-covered catchment in SW-Germany
Agropedology ; Catchment area;Watershed ; Germany ; Gully erosion ; Land use ; Loess ; Sediment budget ; Soil erosion ; Suspended load ; Water quality
The aim of this paper is to present the results of field experiments and to evaluate the efficiency of the applied preventive measures against the background of measured sediment yield. Special attention will be payed to the efficiency
Delivery of Upper-basin sediment to the lower Neuse River, North Carolina, USA
Floodplain ; Fluvial processes ; Indicator element ; Mineralogy ; North Carolina ; Sediment transport ; Sedimentology ; United States
The utility of mica flakes for discriminating between Piedmont and non-Piedmont sources of sediment in the lower Coastal Plain reaches of the Neuse River was established on the basis of an examination of the U.S. National Soils Database and of 26
soil surveys of the North Carolina Coastal Plain. Results demonstrate a dominantly Coastal Plain source and underscore the importance of storage and discontinuous transport in fluvial sediment systems. The upper- and lower-basin sediment dynamics
La répartition des PCB et des pesticides organochlorés a été étudiée dans des sédiments de surface (0-2 cm) et dans les noyaux des sédiments (0-45 cm) de l'ouest de la mer Baltique et des eaux côtières du Mecklembourg-Poméranie occidentale en 1993
Most published interpretations of the stratigraphic data that form the basis for most of the world's Holocene sea-level curves do not consider palaeotsunamis as agents of coastal sedimentation. Biostratigraphic investigations of modern tsunami
sediments are crucial in this regard because they assist greatly in the identification of particular microfossil assemblages that can be used to distinguish coastal sediments deposited by palaeotsunamis from storm surges and also from those sediments
Rates and patterns of contemporary floodplain sedimentation : a case study of the River Culm, Devon, UK
A variety of methods have been used to document contemporary rates of overbank sedimentation along an 11 km reach of the floodplain of the River Culm. These have included measurements of the conveyance loss of suspended sediment between upstream
and downstream measuring stations, the use of sediment traps, and the application of caesium-137 measurements to estimate the rate of accumulation of fine sediment over the past 30 years.
Floodplain sedimentation : a preliminary investigation of contemporary deposition within the lower reaches of the River Culm, Devon, UK
Charge en suspension ; Cours d'eau ; Devon ; England ; Granulométrie ; Géographie physique ; Lit majeur ; Plaine d'inondation ; Royaume-Uni ; Sédimentation
Direct measurements of floodplain sedimentation using plastic grass sediment traps evidence both macro- and microscale spatial variations in deposition which can be related to the duration of inundation, the topography of the floodplain surface
and the flow velocity of the inundating water. Rates of deposition have been estimated from conveyance losses and these have been compared with data obtained from the sediment traps.