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  • Rillerosion in lower Andalusia. A statistical evaluation of rills
  • Andalusia ; Erodibility ; Gully erosion ; Lithology ; Precipitation ; Rill wash ; Slope ; Slope gradient ; Soil erosion ; Soil properties ; Spain
  • The survey of 800 rills served the purpose of registration, evaluation as well as to typify the rills. Geology and sloping-angle are the decisive influencing factors. As dependant parameters length, width and depth of the rills are embraced
  • . In the terrain three main types of rills could be registered. With the help of a variance log the connection between length and depth of a rill can be discribed in an approximation.
  • The rill experiment as a method to approach a quantification of rill erosion process activity
  • Central Pyrenees ; Experimental catchment ; Gully erosion ; Mediterranean area ; Mountain ; Rainfall simulation ; Rill wash ; Spain ; Water erosion ; Watershed
  • Within this paper a standardized method to quantify sediment transport and runoff in natural rills is described. In order to achieve this, several rill experiments (RE) were accomplished in March 2007 in the Arnás catchment in the Spanish Pyrenees
  • . For the characterisation of the rill, slope is measured and micromorphological features like scours are registered. Results and discussion.
  • Hydraulic conditions for rill incision under simulated rainfall : a laboratory experiment
  • Downcutting;Incision ; Experimentation ; Gully erosion ; Hydrodynamics ; Rainfall ; Rill wash;Runoff ; Roughness ; Sediment load ; Sedimentary ; Simulated rainfall ; Soil erosion
  • A series of controlled laboratory experiments were conducted in order to obtain precise data on the hydraulic and sediment transport conditions during rill formation.
  • Incisiones (rills) en campos abandonados : primeras observaciones sobre capacidad de transporte de sedimentos
  • Rills sur les champs abandonnés : Premières observations sur la capacité de charge des sédiments
  • Carrying capacity ; Gully erosion ; Rill wash;Runoff ; Sediment load ; Sediment transport ; Soil erosion ; Wasteland
  • Accuracy of methods for field assessment of rill and ephemeral gully erosion
  • Cultivated land ; Gully erosion ; Methodology ; Navarra ; Rill wash ; Soil erosion ; Spain ; Watershed
  • The aim of this paper is to provide information for a suitable assessment of rill and ephemeral gully erosion with direct measurement methods. Channel size and shape have a great influence on measurement errors.
  • A one-dimensional model for rill inter-rill interactions
  • Experimentation ; Forecast;Prediction ; Model ; Rill wash;Runoff ; Slopes ; Soil erosion
  • The paper describes a water and sediment budget model, averaging across the width of the slope, to explore the balance between processes, and in particular to explore the possibilities for cyclic behaviour, with alternating zones of deep rilling
  • Effect of bed topography on soil aggregates transport by rill flow
  • Grain size distribution ; Rill wash ; Roughness ; Sediment transport ; Soil erosion ; Topography ; Watershed
  • The aim of this work is to investigate the ability of the flow to transport soil aggregates along a real rill at discharges below the formative discharge; and to analyse the influence of the rill pools on this transport process. This subject
  • is an important issue as the transport capacity of rills is highly relevant for phenomena such as soil exportation from fields, catchment-scale sediment redistribution, and sedimentation in streams.
  • Field investigation on rilling in the experimental Sparacia area, South Italy
  • Erodibility ; Erosion rate ; Experimental catchment ; Italy ; Model ; Rill wash ; Semi-arid area ; Sicilia ; Soil erosion ; Water erosion ; Watershed
  • The measurements were made on a plot 6 m wide and 22 m long subjected to natural rainfalls in the experimental Sparacia area located in western Sicily. First the contribution of each component (rill and interrill erosion) to total soil loss
  • was established. Then the analysis allowed establishment of a power relationship between the rill length and the rill volume. Finally, for 3 events detailed information on rill erosion and rill morphology allowed verification of the applicability of WEPP
  • and estimation of the rill erodibility constant.
  • Relationship between discharge, velocity and flow area for rills eroding loose, non-layered materials
  • Belgium ; Carrying capacity ; Catchment area;Watershed ; Channel geometry ; Land use ; Model ; Rill wash;Runoff ; Soil erosion
  • A relationship betwen discharge, flow velocity and flow area in rills is established using data from four field and laboratory studies. The proposed relationship may be used to improve performance of deterministic flow routing models when applied
  • to rilled catchments. Furthermore, it allows the calculation of unit stream power, which has been shown to be related to the transporting capacity of overland fow, in terms of slope and discharge.
  • The influence of subsurface moisture on rill system evolution
  • Canada ; Experimentation ; Gully erosion ; Ontario ; Rill wash ; Slope ; Soil erosion ; Soil moisture ; Threshold
  • This paper describes experiments carried out at the Soil Erosion Laboratory, University of Toronto to provide : observations of rill system development patterns; simultaneous local measurement of surface hydraulic and soil moisture data, together
  • with water and sediment discharge at a terminal weir. The experiments showed complex relationships beween surface and subsurface erosional processes in evolving rill systems, strongly influenced by soil moisture dynamics. The dominant effect of soil moisture
  • Rill hydraulics on a semiarid hillslope, Southern Arizona
  • Arid area ; Arizona ; Channel geometry ; Gully erosion ; Methodology ; Rill wash ; Semi-arid area ; Slope ; United States of America
  • Seventy field experiments were conducted in seven rills located on a semiarid rangeland hillslope underlain by gravelly soils at Walnut Gulch, Arizona. A multiple regression analysis reveals that slope and soil materials, either directly
  • or indirectly through bed roughness, exert almost as much influence on flow velocity as does discharge. Three alternative methods ar developed for predicting flow velocity in the rills under study and give good results with the largest root mean square deviation.
  • Sediment transport in rill flow under deposition and detachment conditions
  • Carrying capacity ; Grain size distribution ; Loam ; Rill wash ; Sediment transport ; Soil erosion ; Water erosion
  • The objectives of this study were to determine whether sediment transport capacity is a unique value for given soil, flow rate, and slope, and to determine if equilibrium sediment concentration in the rill obtained by detachment was different from
  • that observed under depositional conditions. Experiments on a Carmi loam simulated rill erosion under net detachment and net deposition conditions. Discussion of the results.
  • Rill erosion along the thalweg of a hillslope hollow: a case study from the Cotswold Hills, central England
  • Agropedology ; England ; Oxfordshire ; Rill wash ; Sediment transport ; Soil erosion ; United Kingdom ; Watershed
  • This paper describes a rill system that developed in a small agricultural catchment in north Oxfordshire during the winter of 1992-93. The rill system comprised two components: a system of feeder rills along the valley side slopes, which where
  • the results of flow concentration and erosion along wheelings, and a thalweg rill, which formed along a dry valley bottom as a result of surface runoff concentration from the feeder rills. The AA. emphasize the need for a spatially distributed approach
  • Soil freeze-thaw-induced changes to a simulated rill : potential impacts on soil erosion
  • Cold area ; Freeze-thaw cycle ; Freezing ; Gully erosion ; Mass movement ; Model ; Rill wash ; Sediment transport ; Soil erosion
  • The objective of this study was to measure the effects of one of the soil processes that affect rill geometry, soil freeze-thaw (FT) cycling. An unvegetated rectangular rill was subjected to 2 FT cycles, each lasting several days, in a controlled
  • laboratory setting. The FT cycling increased the water content and reduced the cohesion in the surface soil along the rill sufficiently to induce soil slumps and mud flows along the sidewalls of the rill. These mass failures changed the rectangular rill
  • Rill characteristics and sediment transport as a function of slope length during a storm event on loess soil
  • Erosion rate ; Gully erosion ; Loess ; Lublin ; Poland ; Rainstorm ; Rill wash ; Slope gradient ; Soil erosion ; Water erosion ; Watershed
  • The objectives of this study were to characterize rill evolution and sediment transport with its partition into rill and interrill rates using a system of plots with different lengths. Although rill and interrill rates seemed to be similar on all
  • suggested that all the sediment measured at the plot outlet originated from contributing rills and associated contributing rill areas.
  • A note on the development of wash aprons in dune sand, central Australia
  • Arid area ; Australia ; Desert ; Dune ; Geomorphogenesis ; Glacis ; Heavy rain ; Rill wash ; South Australia
  • Sediment sources and sediment transport by rill flow and interrill flow on a semi-arid piedmont slope, southern Arizona
  • Arid land;Arid environment ; Arizona ; Precipitation ; Rainfall simulation ; Rill wash;Runoff ; Sediment budget ; Sediment transport ; Slope ; Soil erosion ; Splash ; United States
  • The purpose of this paper is to compare the characteristics of sediment transport by rill flow with that by interrill flow on the same runoff plot in southern Arizona. A sediment budget for the rill system is established in order to : a) estimate
  • the relative contribution of sediment from the rill and interrill areas, and b) evaluate the response of the rill system to storms of various durations.
  • Rill network development and sediment budgets
  • Canada ; Channel geometry ; Drainage network ; Experimentation ; Gully erosion ; Rill wash ; Sediment budget ; Soil properties ; Water erosion
  • The primary objectives of this initial study were to prepare sediment budgets for rill networks developed on a natural soil under simulated rainfall in a laboratory flume (University of Toronto, Scarborough), and identify the effect of confluences
  • on rill hydraulics and sediment flux patterns. Results indicate the value of detailed sediment budgets in interpreting their water and sediment flux records, and the necessity of linking such measurements for erosion plots and hillslope segments to rill
  • network characterization. Experimental results are consistent with a simple model of rill system evolution.
  • Effects of freshly incorporated straw residue on rill erosion and hydraulics
  • Agricultural practice ; Agropedology ; Belgium ; Erosion control ; Erosion rate ; Experimentation ; Rill wash ; Soil erosion ; Soil properties ; Vegetation ; Water erosion
  • The main aim of this study was to develop an approach to predict soil detachment by rill flow in the presence of freshly incorporated vegetation residue that is compatible with current understanding of rill hydraulics and requires no additional
  • information on rill geometry. Laboratory experiments were carried out. The data are presented and analyzed. An approach to calculate the erosivity of rill flow on surfaces with fresh vegetation residue is proposed. Finally, this new procedure is evaluated
  • Channel width-flow discharge relationships for rills and gullies
  • Belgium ; Discharge ; Europe ; Gully erosion ; Italy ; Land use ; Rill wash ; Runoff ; Slope ; Soil erosion ; Spain ; Water erosion
  • In order to investigate the width-discharge relationships for rills and gullies, a new method is proposed based on field measurements of widths of concentrated-flow erosion channels both upstream and downstream of channel junctions. A total of 322
  • rill and gully channel junctions with various soils and land use types were investigated in Belgium, Italy and Spain. The obtained data confirmed the existence of the power relationship for rills and gullies, with the exponent varying from 0.43
  • for small rills to 0.5 for gullies.