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The rill experiment as a method to approach a quantification of rill erosion process activity

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.

Rillerosion in lower Andalusia. A statistical evaluation of rills

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.

Incisiones (rills) en campos abandonados : primeras observaciones sobre capacidad de transporte de sedimentos

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

Hydraulic conditions for rill incision under simulated rainfall : a laboratory experiment

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.

Accuracy of methods for field assessment of rill and ephemeral gully erosion

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

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

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

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.

Rill hydraulics on a semiarid hillslope, Southern Arizona

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.

The influence of subsurface moisture on rill system evolution

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

Relationship between discharge, velocity and flow area for rills eroding loose, non-layered materials

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.

Sediment transport in rill flow under deposition and detachment conditions

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.

Soil freeze-thaw-induced changes to a simulated rill : potential impacts on soil erosion

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 erosion along the thalweg of a hillslope hollow: a case study from the Cotswold Hills, central England

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

Rill characteristics and sediment transport as a function of slope length during a storm event on loess soil

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

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

Effects of freshly incorporated straw residue on rill erosion and hydraulics

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

Sediment sources and sediment transport by rill flow and interrill flow on a semi-arid piedmont slope, southern Arizona

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

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.

Modelling sediment transport from bare rilled hillslopes by areally averaged transport equations

Modelling sediment transport from bare rilled hillslopes by areally averaged transport equations
Erosion ; Mathematical model ; Model ; Rill wash ; Sediment transport ; Watershed
Treating the dynamics of sediment transport as two-dimensional on interrill-areas and as one-dimensional in rill sections, areally averaged sheet sediment transport (SST) equations are developed. The two-dimensional SST equation is averaged over
an individual interrill-area width and then along the interrill-area length to obtain local-scale areally averaged interrill-area sheet sediment transport equation (local-scale areal averaging). Similarly, the cross-sectional-averaged rill sediment transport
equation is averaged along an individual rill length to obtain local-scale areally averaged rill sediment transport equation.

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