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Entropy-based equation to assess hillslope sediment production

Entropy-based equation to assess hillslope sediment production
Bassin-versant ; Brésil ; Colline ; Entropie ; Erosion ; Modèle ; Modèle mathématique ; Suisse ; Sédimentation ; Versant
Brazil ; Entropy ; Erosion ; Hill ; Mathematical model ; Model ; Sedimentation ; Slope ; Switzerland ; Watershed
Présentation d'une nouvelle équation pour établir la production de sédiments d'un versant de colline basée sur des approches physique et probabiliste.

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

Sedimentation und Sedimentanalytik im Müggelsee. (Sedimentation and sediment analyses in the Müggel Lake)

Sedimentation und Sedimentanalytik im Müggelsee. (Sedimentation and sediment analyses in the Müggel Lake)
Allemagne de l'Est ; Berlin ; Carbone ; Ecosystème ; Géochimie ; Géographie physique ; Lac ; Milieu dulçaquatique ; Müggelsee ; Pollution ; Productivité primaire ; Sédiment lacustre ; Sédimentaire ; Sédimentation
Organically bounded carbon which sediments during the vegetative season in the Müggel Lake being one of the water supply sources for the capital of GDR amounts of 10 % of the carbon quantity which is bounded by primary production during the same
period of time. The sedimentary process and the composition of sediments with regard to their contents of combined carbon, nitrogen and phosphorus and other substances are discussed. Moreover, conclusions are presented concerning the history of this lake

A soil erosion map of the Lesotho lowlands. A case study using visual interpretation of multitemporal Landsat false colour composites in Sediment sources, sediment residence time and sediment transfer-Case studies of soil erosion in the Lesotho lowlands.

A soil erosion map of the Lesotho lowlands. A case study using visual interpretation of multitemporal Landsat false colour composites in Sediment sources, sediment residence time and sediment transfer-Case studies of soil erosion in the Lesotho
The project is made within the framework of a larger research programme on the relations between sediment production, sediment residence time and sediment delivery in different climates and geomorphological environments.

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.
Averse ; Bassin-versant ; Bilan sédimentaire ; Erosion des sols ; Géographie physique ; Modélisation ; Production sédimentaire ; Ressources en eau
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

Measurement and prediction of sediment production from unpaved roads, St John, US Virgin Islands

Measurement and prediction of sediment production from unpaved roads, St John, US Virgin Islands
The main objectives of this study were to : measure sediment production rates at the road segment scale; evaluate the importance of precipitation, slope, contributing area, traffic, and grading on road sediment production; develop an empirical road
erosion predictive model; and compare the measured erosion rates to other published data. Sediment production from 21 road segments was monitored with sediment traps from July 1998 to November 2001. The AA. compare the measured road sediment production

Using Be 10 and Al 26 to determine sediment generation rates and identify sediment source areas in an arid region drainage basin

Using Be 10 and Al 26 to determine sediment generation rates and identify sediment source areas in an arid region drainage basin
Arid area ; Arizona ; Grain size distribution ; Isotope dating ; Model ; Sediment budget ; Sediment transport ; United States of America ; Watershed ; Weathering
the length of Yuma Wash, the AA. identify significant sediment source areas. Nuclide concentrations in upland basins represent the production rate of sediment from the weathering of bedrock (sediment generation). Nuclide concentrations in main stem samples
In this work, the AA. apply the techniques developed for determining basin-wide sediment generation rates in small basins to both the entire Yuma Wash drainage and to smaller sub-basins of the Wash. Tracing nuclide concentrations in sediment along
reflect both upland sediment generation and the long-term effects of sediment storage and reworking.

Impact of afforestation on hydrological response and sediment production in a small Calabrian catchment

Impact of afforestation on hydrological response and sediment production in a small Calabrian catchment
Calabria ; Deforestation ; Experimentation ; Italy ; Mediterranean area ; Rill wash ; Sediment transport ; Soil erosion ; Watershed
This study was carried out to provide data on the spatial variability of runoff and sediment production on lithologically uniform hillsllopes which differ in aspect, slope and vegetation. Such data can be used to adjust forestry practices for more
effective control of runoff and sediment output.

Sediment production within the drainage basin

Sediment production within the drainage basin
Sedimentological studies in the Cachi reservoir, Costa Rica. Sediment inflow, reservoir sedimentation, and effects of flushing
Catchment area;Watershed ; Costa Rica ; Land use ; Landslide ; Mass movement ; Sediment transport ; Soil erosion
The aim of this section is to investigate erosion at different land use by comparing sediment transport data from stations within the basin.

Carbon isotope composition of lake sediments in relation to lake productivity and radiocarbon dating

Carbon isotope composition of lake sediments in relation to lake productivity and radiocarbon dating
Canada ; Carbone ; Datation C 14 ; Géochimie ; Isotope ; Ontario ; Paléo-environnement ; Paléo-écologie ; Quaternaire ; Sédiment lacustre
C14 dating ; Canada ; Carbon ; Geochemistry ; Isotope ; Lacustrine sediment ; Ontario ; Paleo-ecology ; Paleo-environment ; Quaternary
The purpose of this paper is to contribute to developing criteria for evaluating the validity of radiocarbon dates of lake sediments from basins in calcareous terrain. In particular, the AA. test the hypothesis that the 13C content of lake sediments

Estimation of sedimentation rates in the Chemeron Reservoir

Estimation of sedimentation rates in the Chemeron Reservoir
Accumulation rate ; Applied geomorphology ; Dam ; Forecast ; Kenya ; Sediment budget ; Sediment transport ; Soil erosion ; Watershed
largely on erosion studies carried out since dam construction and uses all available soil loss information for the Chemeron catchment with estimates for sediment production from bank erosion and road and path networks to estimate annual sediment production
Water supply from the reservoir has transformed land use patterns on the Njemps Flats, providing for irrigated vegetable and cereal cultivation. No reliable sediment yield estimates were available prior to dam construction. This paper is based
. Using best available sediment delivery ratios and reservoir trap efficiency figures, a current sedimentation rate is estimated.

Effect of the small reservoirs on the sediment delivery from Bîrlad drainage basin

Effect of the small reservoirs on the sediment delivery from Bîrlad drainage basin
Hydrodynamics ; Lake ; Reservoirs ; Romania ; Sediment load ; Stream
On y analyse le rôle des petits lacs anthropiques dans la rétention des sédiments transportés par les rivières du bassin de Bîrlad. De la production totale de sédiments du bassin de Bîrlad (environ 740 000 m3/an) à la sortie du bassin arrivent
seulement 4 %; 5,65 % de la production est retenue par les lacs anthropiques et le reste est stocké dans le bassin.―(M. Vârlan).

Moraine formation in northwestern Ontario : product of subglacial fluvial and glaciolacustrine sedimentation

Moraine formation in northwestern Ontario : product of subglacial fluvial and glaciolacustrine sedimentation
Selon les AA. les sédiments de ces moraines représentent des dépôts de sédimentation rapide associés à de grandes crues qui ont provoqué une instabilité passagère du système hydrographique et (ou) un déferlement antérieur à la sédimentation frontale

Observations on the effects of urbanization on runoff and sediment production in Singapore

Observations on the effects of urbanization on runoff and sediment production in Singapore

Sediment-magnetic signature of land-use and drought as recorded in lake sediment from south-central Minnesota, USA

Sediment-magnetic signature of land-use and drought as recorded in lake sediment from south-central Minnesota, USA
Etats-Unis ; Holocène ; Minnesota ; Occupation humaine ; Paléo-environnement ; Paléoclimat ; Susceptibilité magnétique ; Sécheresse ; Sédiment lacustre ; Sédimentologie ; Utilisation du sol ; Variabilité climatique
Climatic variability ; Drought ; Holocene ; Human occupation ; Lacustrine sediment ; Land use ; Magnetic susceptibility ; Minnesota ; Palaeo-environment ; Palaeoclimate ; Sedimentology ; United States of America
Sediment magnetic properties of a short core from Sharkey Lake record the effects of Euroamerican settlement and climate change over the last 150 yr. The onset of European-style farming led to increase erosion, reflected in high values
of concentration-dependent parameters such as magnetic susceptibility (k), Isothermal Remanent Magnetization (IRM), and Anhysteretic Remanent Magnetization (ARM). High organic productivity in the lake during 1920s to 1940s drought increased the authigenic component
resulting in highly magnetic fine-grained sediment. The effects of dissolution and the superposition of climate and land-use signals complicate the use of recent sediments as modern analogs for sediment magnetic analyses.

Glacier fluctuations, suspended sediment flux and glacio-lacustrine sediments

Glacier fluctuations, suspended sediment flux and glacio-lacustrine sediments
Bilan de masse ; Fluctuation du glacier ; Glacier ; Holocène ; Lac proglaciaire ; Modélisation ; Paléoclimatologie ; Suède ; Sédiment lacustre ; Variabilité climatique
Climatic variability ; Glacier ; Glacier fluctuation ; Glacier mass balance ; Holocene ; Lacustrine sediment ; Modelling ; Palaeoclimatology ; Proglacial lake ; Sweden
balance and resulting glacier volume and length variations; glacier sediment production and sediment fluxes out from glaciers and proglacial areas; and finally the glacio-lacustrine record of glacier variations. They exemplify the first two components
The AA. review the different factors that potentially complicate inferences about climate-induced glacier response based on proglacial lake sediments. They discuss each component separately, starting with the climate forcing on the glacier mass
with data from Storglaciären, northern Sweden, and its proglacial river and surroundings. The AA. conclude that it is necesary to consider all possible influencing factors in order to derive reliable palaeoclimate data from lacustrine sediment sequences.

Sediment yield determination using uranium-series radionuclides: the case of The Wash and Fenland drainage basin, eastern England

Sediment yield determination using uranium-series radionuclides: the case of The Wash and Fenland drainage basin, eastern England
England ; Geochemistry ; Intertidal zone ; Isotope analysis ; Sediment budget ; United Kingdom ; Uranium ; Watershed
Water and sediment samples were collected from the Fenland drainage bassin to assess the fluvial contribution to the sediment budget of The Wash, on the east coast of England. Using the uranium-series disequilibrium found in the products
of the weathering system (river sediment and water), the ratio of material carried in solid form to that dissolved was assessed and the total flux of weathered material (sediment yield) was quantified. The results reinforce the argument that sediment reworking
within The Wash and erosion of thhe adjacent coasts and sea beds are important sources of sediment for the intertidal flats and salt marshes.

Interstorm surface preparation and sediment detachment by vehicle traffic on unpaved mountain roads

Interstorm surface preparation and sediment detachment by vehicle traffic on unpaved mountain roads
The AA. use rainfall simulation to investigate sediment production associated with one common maintenance practice in northern Thailand, and to study sediment detachment by motorcycles and pickup trucks on unpaved roads. Additionally
they incorporate physical property measurements, road usage information and simulation results to determine links between sediment production on roads and interstorm preparation. The AA. focus on processes that determine sediment production during typical seasonal

Preliminary modelling of sediment production and delivery in the Xihanshui River basin, Gansu, China

Preliminary modelling of sediment production and delivery in the Xihanshui River basin, Gansu, China
Sediment sources and sediment delivery under environmental change. Special issue
Bank erosion ; China ; Gansu ; Gully erosion ; Land use ; Mass movement ; Model ; Sediment budget ; Sediment transport ; Soil conservation ; Soil erosion ; Watershed
This paper describes the preliminary application of a spatially-distributed method to quantify patterns and rates of sediment production in the Xihanshui basin, a tributary of the upper Yangtze; and to predict its routing to a downstream point
is therefore to assess the relative importance of sediment production processes under different climate and land cover conditions, and the controls of the spatial structure of delivery ratios within this large catchment, rather than to make explicit forecasts
of sediment production and yield for practical purposes.

Production et accumulation de sédiments biogènes dans les estrans sableux

Production et accumulation de sédiments biogènes dans les estrans sableux
Action biogène ; Bretagne ; Dynamique littorale ; Estran ; Finistère ; France ; Littoral ; Micro-organisme ; Sable ; Sédiment marin ; Sédimentologie
Biogenic process ; Brittany ; Coastal dynamics ; Coastal environment ; Finistère ; Foreshore ; France ; Marine sediment ; Micro-organism ; Sand ; Sedimentology
-organismes vivant dans l'avant-plage et sur les platiers rocheux dans la production de ces sédiments bioclastiques.
organismes producteurs, origines et de comprendre la redistribution de ces particules organogènes sur l'estran qui dépend des conditions hydrodynamiques et sédimentaires locales. Mise en évidence de l'importance des apports locaux par les micro et macro

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