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  • Aerodynamic roughness of gravel surfaces
  • Aeolian features ; Arid area ; China ; Desert ; Experimentation ; Grain size distribution ; Gravel ; Model ; Roughness ; Sediment transport
  • The AA. report detailed results with respect to the aerodynamic roughness of different gravel surfaces from wind tunnel experiments. With the philosophy that aerodynamic roughness of gravel surfaces is a function of gravel size, spacing and the near
  • -surface airflow characteristics, the specific purposes are to define the change of aerodynamic roughness length with wind speed, gravel size and coverage and roughness Reynolds number; and establish prediction models for aerodynamic roughness length
  • of gravel surfaces.
  • Mixed sand and gravel beaches
  • Movement of cobbles in a gravel-bed stream during a flood season
  • Fluvial geomorphology : initial motion of bed material in gravel-bed rivers
  • This review deals with the entrainment of gravel bedload : theory, laboratory studies, field studies, the relevance of studies in nonfluvial environments and the significance of studies of bedload entrainment.
  • Wandering gravel-bed rivers
  • Ce court article caractérise le phénomène courant dans la région cordillère de l'ouest canadien des wandering gravel-bed rivers . - (C. Risi).
  • The well-tempered garden : gravel and topiary in California
  • Discussion of a garden style common in Albany, California and spread there by imitation of controlling nature on individual lots by pruning trees and replacing lawns with gravel. - (DWG)
  • Entrainment, displacement and transport of tracer gravels
  • This paper addresses several aspects of the collection, analysis and interpretation of tracer gravel observations, with the general objectives of increasing the information yield of a tracer gravel programme and improving the accuracy of transport
  • estimates from tracer gravels. The expected variation with grain size of tracer displacement length is developed and illustrated using displacement lengths calculated from measurements of entrainment, surface size distribution and transport rate
  • Most of the wedge casts occur in angular slope gravel, fluvial or fluvio-glacial gravels, the largest reaching a width of 2-3 m and a depth of 3-5 m. Upturning of the host gravel occurs, especially with the larger casts. Slump or sag structures
  • in the fill are limited to platy gravels| in other gravels, the wedge fill is characterized by very steeply dipping clasts. Though no means of precise dating is available, it is throught that the wedge casts formed in the later part of the last glaciation.
  • Assessing potential abiotic and biotic complications of crayfish-induced gravel transport in experimental streams
  • This study used a representative and replicated design of artificial stream experiments to assess how an organism of intermediate size and abundance, a benthic crayfish, affects the transport of gravel across a gradient of an abiotic and a biotic
  • factor that potentially affect crayfish behaviour, and in turn could complicate the crayfish-induced gravel transport. This study also assesses how crayfish abundance in terms of their biomass affects the gravel transport across a variety of experimental
  • Gravel sediment routing from widespread, low-intensity landscape disturbance, Current River basin, Missouri
  • Carrying capacity ; Drainage network ; Fluvial erosion ; Gravel ; Land use ; Missouri ; River bed ; Sediment load ; Sediment transport ; Spatial distribution ; Stream ; United States of America ; Watershed
  • During the last 160 years, land-use changes in the Ozarks have had the potential to cause widespread, low-intensity delivery of excess amounts of gravel-sized sediment to stream channels. Previous studies have indicated that this excess gravel
  • bedload is moving in wave-like forms through Ozarks drainage basins. The objective of this report is to evaluate the longitudinal distribution of gravel along the mainstem of the Current River and determine the spatial and historical factors that have
  • resulted in gravel accumulations.
  • Soil surface evaporation processes under mulches of different sized gravel
  • Agricultural practice ; Agropedology ; China ; Evaporation ; Experimentation ; Gravel ; Litter ; Loam ; Northern China ; Soil properties ; Soil water
  • In this study, a series of simulation experiments were conducted to study the effects of gravel mulches of different sizes on evaporation process from soil surface. Four mulch treatment levels were used. The major objectives were : 1) to estimate
  • the water conservation of the gravel mulches on the cumulative soil evaporation and soil evaporation rate; 2) to study the effects of the gravel size on the evaporation processes and water conservation.
  • Stone and gravel contents of arable soils influence estimates of C and N stocks
  • In this study, relative volumes of stones and gravel were investigated in the top soils, i.e. down to 30 cm depth, of five Swedish arable sites. Bulk density and gravel volume were determined by soil coring and stone volume using the rod penetration
  • method. A function for estimation of relative stone volume from mean penetration depth was developed. The results showed that although the relative volumes of stones and gravel were small, at most 8%, neglecting the volume occupied by rock fragments led
  • to an overestimation of C and N stocks by 8-9%. It was concluded that the inclusion of stone and gravel volume of arable soils may be important if nutrient stocks of different sites are compared, or the effects of land use changes are scaled up to regional or global
  • Quantitative determination of the activity of within-reach sediment storage in a small gravel-bed river using transit time and response time
  • Carrying capacity ; Channel geometry ; Grain size distribution ; Gravel ; Methodology ; Quantitative analysis ; River bed ; Scotland ; Sediment load ; Storage site ; Stream ; Tracer ; United Kingdom
  • This paper demonstrates how fractional sediment storage activity in a gravel-bed river can be quantified using a within-reach sediment budget and reservoir theory. Deployment of magnetic tracer particles allows accurate characterisation of sediment
  • fluxes in gravel-bed rivers and provide the opportunity to quantify storage activity using reservoir theory. The results suggest that transit time is difficult to determine from tracer studies in gravel-bed rivers. Consequently, a refinement of transit
  • The gravel-sand transition: flume study of channel response to reduced slope
  • Base level ; Carrying capacity ; Experimentation ; Fluvial processes ; Grain size distribution ; Gravel ; Hydraulic works ; Model ; River bed ; Sand ; Slope gradient ; Stream flow
  • This paper reports flume experiments with a bimodal gravel/sand bed and sediment feed, designed to investigate river channel response to declining slope. The AA. simulated a series of sites along a concave profile approaching a local base level
  • and undergoing a transition from gravel to sand bed; it also models the effect of a rise in base level on a fixed site. The results support the view that the gravel-sand transition along river channels with a local base level control is assisted by positive
  • Debris and sheet flow dominated gravels in the Sabarmati basin of Western India
  • Alluvial cone ; Alluvium ; Graben ; Gravel ; India ; Lithology ; Palaeohydrology ; Sedimentary structure ; Tectonics ; Watershed
  • The alluvial gravels in the Sabarmati river basin were deposited in a huge graben bounded by faults related to Cambay basin tectonics. The gravels were accumulated in the depression by an ancient Sabarmati in the form of debris and stream flows
  • as revealed by their lithological and textural characteristics. The present Sabarmati behaving as an erosional river has only exposed the gravels along its high cliffs from Valasana in the north to Sadra in the south, defining the proximal and distal
  • Dynamics of gravel in the superficial sediments of the Flemish Banks, southern North Sea in The Quaternary and Tertiary geology of the Southern Bight, North Sea.
  • Although it is obvious that the gravels in the Flemish Banks consist of three main deposits, it is very hard to stake them out. Due to the Holocene marine transgressions the gravels are becoming a mixture of southern coming, Rhine and Meuse
  • , and local clasts. In consequences of the tidal stream generated erosion, a coarse gravelly lag deposit develops in the interbank channels. Both grain-size and petrographic data demonstrate gravel paths leaving these channels. They indicate a net NNE
  • transport of fine gravel oblique to the crest of the ridges.
  • Gravel-sand mulch for soil and water conservation in the semiarid loess region of northwest China
  • Agricultural practice ; Agricultural productivity ; Arid area ; China ; Gravel ; Loess ; North-Western China ; Sand ; Semi-arid area ; Soil ; Soil conservation ; Soil properties ; Soil water
  • This study investigates the effects of gravel-sand mulch on hydrological processes, thermal properties, soil erosion and soil productivity as well as plant growth. It also provides a general idea of the principles and methods of management
  • of the Gravel-Sand Mulched Fields (GSMF). The results show that surface gravel-sand mulch provides a more favorable environment for plant growth than non-mulched fields in the highly erodible loess area of northwest China.
  • Bibliography ; Carrying capacity ; Fluvial processes ; Gravel ; Hydrodynamics ; River bed ; Sediment transport ; Sedimentology ; Turbulence
  • This progress report reviews the research into the processes of : 1) coarse surface layers; 2) armour versus pavement; 3) bed surface structure and sediment transport; 4) imbrication; 5) small- and medium-scale gravel bedforms; 6) gravel bedforms
  • Classification ; Geomorphology ; Gravel ; Hungary ; Pest ; Plain ; Sedimentology
  • The author carried out rolling examination of 1108 river origin gravel pieces originating from the Budapest area to try to answer the question, if the gravel sediments could be classified based on the rolling characteristics data. - (ZK)
  • Discrimination of channel patterns for gravel- and sand-bed rivers
  • Braided channel ; Discriminant analysis ; Gravel ; Meander ; River bed ; Runoff ; Sand ; Shear stress ; Stream ; Stream flow
  • Based on data from around 200 alluvial rivers in several countries, a systematic comparison of flow shear stress and stream power has been made between sand- and gravel-bed rivers. The formation of channel pattern can be regarded as the outcome