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Reservoir effects on sediment yield
Charge solide ; Cours d'eau ; Géographie physique ; Réservoir ; Sédimentation

Sediment yield modelling in Erosion and sediment yield : some methods of measurement and modelling.

Sediment yield modelling in Erosion and sediment yield : some methods of measurement and modelling.
Sediment yield models vary considerably to accomodate the wide range of water resources problems where sediment yield estimates are needed : erosion control planning, water resources planning and design, water quality modelling. The simplest models

Physiographically controlled allometry of specific sediment yield in the Canadian Cordillera : a lake sediment-based approach

Physiographically controlled allometry of specific sediment yield in the Canadian Cordillera : a lake sediment-based approach
Bassin-versant ; Bilan sédimentaire ; British Columbia ; Canada ; Charge en suspension ; Modèle ; Montagne ; Sédiment lacustre ; Sédimentologie ; Transfert sédimentaire
British Columbia ; Canada ; Lacustrine sediment ; Model ; Mountain ; Sediment budget ; Sediment transfer ; Sedimentology ; Suspended load ; Watershed
It is generally supposed that specific sediment yield declines as the drainage basin area increases, as part of the mobilized sediment becomes trapped in the downstream cascade of storage zones. Using a larger data set of lake sediment-based
estimates of long-term sediment yield, sub-regional patterns of specific yield have been investigated for the Canadian Cordillera. The results suggest that no single model of sediment yield is adequate to describe sediment transfer processes in the Canadian

Model study of the relationship between sediment yield and river basin area

Model study of the relationship between sediment yield and river basin area
Italy ; Land use ; Model ; Portugal ; Precipitation ; Sediment budget ; Semi-arid area ; Simulation ; Soil erosion ; Watershed
The SHETRAN physically based, spatially distributed model is used to investigate the scaling relationship linking specific sediment yield to river basin area, for two contrasting topographies of upland and more homogeneous terrain and as a function
of sediment source, land use and rainfall distribution. The sediment yield/basin area relationship can be inverse or direct, depending on basin characteristics. There still remains, therefore, considerable scope for defining a universal scaling law
for sediment yield.

Sediment storage and yield in an urbanized karst watershed

Sediment storage and yield in an urbanized karst watershed
Cave ; Doline ; Karst ; Sediment budget ; Sediment transport ; Tennessee ; United States of America ; Urban area ; Watershed
This paper presents a preliminary assessment of fluvial sediment storage and yield in an urbanized, karst watershed. The AA. aim to identify and quantify the function of caves and sinkholes within the context of a sediment budget with 3 specific
objectives : to investigate the function (source or sink) of sinkholes with respect to sediment transport; to demonstrate how sinkhole sedimentation rates can be used as an indicator of basin sediment yield from some sinkhole drainage basins; and to determine
the relative contribution of a major cave system to a preliminary sediment budget for a karst watershed.

A global survey of sediment yield

A global survey of sediment yield
Runoff has been used as a variable representing climatic conditions. Relationships between runoff and sediment yield are shown in diagrams for different climatic groups. There is no universal statistically significant global correlation between
runoff and sediment yield which is valid for all climates. The global pattern in net erosion is shown in a separate map.

Hillslope failure and sediment yield in japanese regions with different storm intensity

Hillslope failure and sediment yield in japanese regions with different storm intensity
Climatic variation ; Japan ; Precipitation ; Rainstorm ; Sediment budget ; Slope ; Slope gradient ; Soil erosion ; Watershed
This paper discusses the effects of storm intensity on the magnitudes of slope failure and sediment yields in Japan. Data were analyzed for 813 river basins that experienced storm-induced failure as well as 30 basins with sediment yield data
. The basins were grouped into 3 categories according to storm intensity to examine the relation between rainfall and erosion magnitudes. Slope-failure magnitudes and sediment yields are also affected by hillslope inclination. The effect of hillslope

Lake-sediment-based evaluation of recent sediment yield from a small appalachian watershed, Thompson lake, Virginia

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.

Effects of rock fragment size and cover on overland flow hydraulics, local turbulence and sediment yield on an erodible soil surface

Effects of rock fragment size and cover on overland flow hydraulics, local turbulence and sediment yield on an erodible soil surface
Experimentation ; Rill wash ; Runoff ; Sediment budget ; Sediment transport ; Slope ; Soil erosion ; Turbulence
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
is suggested. Sediment yield from non-cohesive soils might then be estimated by a combination of sediment transport and scour formulas.

Sediment yields and sources in a Welsh upland lake-catchment during the past 800 years

Sediment yields and sources in a Welsh upland lake-catchment during the past 800 years
Analyse isotopique ; Datation ; Holocène ; Paléogéographie ; Paléomagnétisme ; Quaternaire ; Royaume-Uni ; Sédimentation lacustre ; Transport sédimentaire ; Wales
Dating ; Holocene ; Isotope analysis ; Lacustrine sedimentation ; Paleogeography ; Paleomagnetism ; Quaternary ; Sediment transport ; United Kingdom ; Wales
Estimates of suspended sediment yield over the past 800 years have been derived from a whole-basin study of lake sediments in Llyn Geirionydd, North Wales. Magnetic and physical sediment properties were used to correlate a suite of cores to a master
chronology based on 210Pb and 14C dates. The sources of sediment within the catchment were identified by comparing the magnetic and heavy metal properties of sediments, soils, and stream sediments.

Sediment yield mapping using small dam sedimentation surveys, Southern Tabelands, New South Wales

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.

Factors controlling sediment yield from small intensively cultivated catchments in a temperate humid climate

Factors controlling sediment yield from small intensively cultivated catchments in a temperate humid climate
Belgium ; Cultivated land ; Model ; Multiple regression ; Sediment budget ; Soil erosion ; Temperate zone ; Watershed
Data on sediment yield from 26 small cultivated catchments (10-10 000 ha) in central Belgium were collected based on sedimentation rates in small flood retention ponds. Various catchment properties were analysed in order to understand the large
variation in observed sediment yield. A multiple regression model including 3 morphological catchment properties is a valuable tool to predict total sediment yield from catchments in central Belgium. This model has an efficiency of 0.81. The importance
of spatially distributed parameters within catchments are some of the major reasons that the proposed model does not explain all observed variation in sediment yield.

Predicting catchment sediment yield in Mediterranean environments : the importance of sediment sources and connectivity in Italian drainage basins

Predicting catchment sediment yield in Mediterranean environments : the importance of sediment sources and connectivity in Italian drainage basins
Forecast ; Italy ; Landslide ; Mediterranean area ; Model ; Sediment budget ; Soil erosion ; Watershed
From reservoir sedimentation data of 44 Italian catchments, it appeared that there was a (non-significant) positive relation between catchment area and sediment yield. This is in contrast to what is generally expected from the theory of decreasing
sediment delivery rates with increasing catchment area. Furthermore, this positive relation suggests that processes other than upland erosion are responsible for catchment sediment yield. Here, the AA. explore the potential of the Factoring Scoring Model
(FSM) and the Pacific Southwest Interagency Committee (PSIAC) model to predict sediment yield and indicate the most important sediment sources.

Modern sediment yield compared to geologic rates of sediment production in a semi-arid basin, New Mexico : assessing the human impact

Modern sediment yield compared to geologic rates of sediment production in a semi-arid basin, New Mexico : assessing the human impact
Arid area ; Erosion rate ; Gully erosion ; Human impact ; Isotope analysis ; New Mexico ; Pastureland ; Sediment budget ; Semi-arid area ; Soil erosion ; United States of America ; Watershed
In the semi-arid Arroyo Chavez basin, the AA. compare modern short-term sediment yields measured using sediment traps and dams to geologic rates of sediment production estimated using cosmogenic nuclides. Contrasting modern, short-term rates
of sediment yield with long-term geologic or natural rates of sediment production allows assessment of human influences on erosion rates. At Arroyo Chavez, the AA. conclude that grazing is the likely cause for higher sediment yields on the alluvial valley

Reservoir trap efficiency in Erosion and sediment yield : some methods of measurement and modelling.

Reservoir trap efficiency in Erosion and sediment yield : some methods of measurement and modelling.
Bassin-versant ; Expérimentation ; Géographie physique ; Lac artificiel ; Sédimentation ; Technique de recherche
An explanation of what happens in agricultural reservoirs during an inflow event and, using a flow diagram, the various parameters that influence sediment trap efficiency.

Sediment yield and delivery in the blanket peat moorlands of the southern Pennines

Sediment yield and delivery in the blanket peat moorlands of the southern Pennines
This research attempts to add to the existing knowledge of peat-covered catchments by adopting investigations at various temporal and spatial scales to illuminate patterns of sediment erosion and sediment yield in peat-covered catchments.

The impact of weather patterns on historic and contemporary catchment sediment yields

The impact of weather patterns on historic and contemporary catchment sediment yields
Bassin-versant ; Bilan sédimentaire ; Changement global ; Circulation atmosphérique ; Cyclone ; England ; Erosion des sols ; Lac ; Précipitation ; Royaume-Uni ; Sédiment lacustre ; Type de temps ; Utilisation du sol ; Variation climatique
Atmospheric circulation ; Climatic variation ; Cyclone ; England ; Global change ; Lacustrine sediment ; Lake ; Land use ; Precipitation ; Sediment budget ; Soil erosion ; United Kingdom ; Watershed ; Weather type
Lake sediment-based estimates of sediment yield have frequently been used to reconstruct changing patterns of sediment supply arising from environmental change. Such analyses have often emphasized the importance of anthropogenic factors. This paper
examines several U.K. sediment yield chronologies within the context of mesoscale atmospheric circulation patterns. Changes in the frequency of the winter cyclonic Lamb weather type since 1861 were found to account for a significant proportion
of the variation in sediment yields. The results also have implications given the potential geomorphological consequences of global climate change.

Sediment yield from some third order basins on the basement complex rocks in southwestern Nigeria

Sediment yield from some third order basins on the basement complex rocks in southwestern Nigeria
Dissolved sediment yield is greater than suspended sediment yield in almost all the basins and with a ratio varying from 0.7 to 6.8. This may show that the dominant geomorphological process in this environment is chemical rather than mechanical
erosion or that factors such as the nature of the farming system exist which inhibit the delivery of suspended sediments obtained from basin slopes to river channels.

Impacts of socio-economic factors on sediment yield in the Upper Yangtze River

Impacts of socio-economic factors on sediment yield in the Upper Yangtze River
Action anthropique ; Aménagement hydraulique ; Bassin-versant ; Chine ; Corrélation ; Densité de population ; Déboisement ; Erosion des sols ; Indicateurs socio-économiques ; Pente de versant ; Propriétés du sol ; Sichuan ; Taux de sédimentation
Agricultural land use ; China ; Correlation ; Deforestation ; Human impact ; Hydraulic works ; Population density ; Sedimentation rate ; Sichuan ; Slope gradient ; Socio-economic indicators ; Soil erosion ; Soil properties ; Watershed ; Yangtze
Taking Sichuan Province and Chongqing City as an example, this paper studies the relationship between socio-economic factors and sediment yield in the Upper Yangtze River based on section data in 1989 and 2007. The results show that sediment yield
is significantly correlated with population density and cultivated area, in which the former appears to be more closely related to sediment yield. Moreover, in the relation of sediment yield vs. population density, a critical value of population density exists
. This phenomenon essentially reflects the influence of natural factors, such as topography, precipitation and soil property, and some human activities on sediment yield. It is also found that population tends to move from the areas with bad environment and high
sediment yield to the areas with more comfortable environment and less sediment yield.

Variability of dry sediment bulk density between and within retention ponds and its impact on the calculation of sediment yields

Variability of dry sediment bulk density between and within retention ponds and its impact on the calculation of sediment yields
Belgium ; Grain size distribution ; Impact ; Organic materials ; Reservoir ; Sediment budget ; Sedimentology ; Soil erosion ; Watershed
be evaluated if the various existing dry sediment bulk density prediction techniques for large reservoirs can be used in another environment, i.e. small ponds, and what the implications of their use are for the calculation of sediment yield.
The objectives of this study are to make an assessment of the variability in dry sediment bulk density (dbD) between and within small flood retention ponds in central Belgium and to look at the factors controlling this variability. It will further

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