Effects of rainfall, overland flow and their interactions on peatland interrill erosion processes

Studies of soil erosion in upland and marginal upland Britain are reviewed. Processes affecting soil erosion and runoff are described in marginal upland improved pastures of differing age in the Clwydian Hills, including one which was cultivated twice during the study period. A Gerlach-type trough was designed for trapping sediment and filtered runoff from bounded plots and for operating under grazing. Erosion and runoff amounts are interpreted in the light of ground cover, rainfall amounts and intensity, the action of grazing stock and other animals, and other influences. The chief erosion processes are the action of animals and surface wash by unconcentrated overland flow; no rilling occurred. The significance of particle size of eroded sediment is discussed.

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Gaining insights into interrill erosion processes using rare earth element tracers

Geoderma ◽

10.1016/j.geoderma.2017.04.004 ◽

2017 ◽

Vol 299 ◽

pp. 63-72 ◽

Cited By ~ 18

Author(s):

X.C. Zhang ◽

M.A. Nearing ◽

J.D. Garbrecht

Keyword(s):

Rare Earth ◽

Rare Earth Element ◽

Earth Element ◽

Erosion Processes ◽

Interrill Erosion

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Rare earth elements tracing interrill erosion processes as affected by near-surface hydraulic gradients

Soil and Tillage Research ◽

10.1016/j.still.2020.104673 ◽

2020 ◽

Vol 202 ◽

pp. 104673 ◽

Cited By ~ 1

Author(s):

Chenfeng Wang ◽

Bin Wang ◽

Yujie Wang ◽

Yunqi Wang ◽

Wenlong Zhang ◽

...

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Near Surface ◽

Erosion Processes ◽

Hydraulic Gradients ◽

Interrill Erosion

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Soil erosion processes. I. The relative importance of rainfall detachment and dunoff entrainment

Soil Research ◽

10.1071/sr9910671 ◽

1991 ◽

Vol 29 (5) ◽

pp. 671 ◽

Cited By ~ 39

Author(s):

APB Proffitt ◽

CW Rose

Keyword(s):

Soil Erosion ◽

Overland Flow ◽

Water Flux ◽

Equilibrium Concentration ◽

Sediment Concentration ◽

Soil Types ◽

Relative Importance ◽

Runoff Water ◽

Erosion Processes ◽

Volumetric Flux

Experiments carried out in a simulated-rainfall tilting-flume facility are reported in which sediment concentrations (c) in runoff water resulting from overland flow only, or from a combination of rainfall and overland flow, were measured under controlled conditions using a series of slopes (0.1, 05, 1, 3 and 5%). The mixture of rainfall (of rate 100 mm h-1) and runon of water at the top of the flume were arranged to provide a constant volumetric flux (1.0x10-3 m3 m-l s-1) at exit from the 5.8 m long flume. Two contrasting soil types were studied: a cracking clay (black earth or vertisol), and a slightly dispersive sandy clay loam (solonchak or aridisol). Two major processes which can contribute to soil erosion under rainfall are rainfall detachment and runoff entrainment. For both soil types, c was generally highest for the steepest slope and decreased with slope. For constant rainfall and/or runoff conditions, c generally decreased with time until an equilibrium concentration was reached. At this equilibrium, the relative importance of rainfall detachment and entrainment in terms of soil loss was dependent on soil type and streampower which incorporates effects of slope and water flux. For streampowers <0.1 W m-2 for the black earth, and <0.3 W m-2 for the solonchak, the greatest contribution to c was by rainfall detachment, whilst at greater streampowers entrainment was the dominant contributor to c. At any streampower, the contribution by rainfall detachment was greater for the weakly structured solonchak than for the well aggregated black earth. At lower strearnpowers, the interaction between erosion processes was found to give higher c than the sum of both sediment concentrations resulting from the separately occurring processes. At streampowers greater than approximately 0.5 W m-2, rainfall reduced eroded sediment concentration by suppressing rill development. The findings in this study suggest that both runoff entrainment and rainfall detachment can contribute to sediment concentration from 'interrill' areas.

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Aplicação da Micromorfologia de Solos ao Estudo de Sedimentos Alúvio-Coluviais em Cabeceiras de Vale

Pesquisas em Geociências ◽

10.22456/1807-9806.19509 ◽

2006 ◽

Vol 33 (2) ◽

pp. 3 ◽

Cited By ~ 2

Author(s):

GLAUCIA MARIA DOS SANTOS SILVA FERREIRA ◽

MARCELO ACCIOLY TEIXEIRA DE OLIVEIRA

Keyword(s):

Overland Flow ◽

Gully Erosion ◽

Aerial Photographs ◽

Sedimentary Structures ◽

Erosion Processes ◽

Hillslope Evolution ◽

Common Process ◽

Geomorphological Units ◽

The Relationship ◽

Micromorphological Analysis

Previous work on the role played by valley head areas in humid regions brought to light geomorphological units of the drainage net in which erosion and sedimentation would tend to be recurrent in time and space. Valley heads studied in Brazil had already proved to be very sensible to gully erosion processes, which, besides its importance to land degradation, also is a common process of hillslope evolution on humid regions. Gully erosion carries out from slopes important amounts of sediments, which may either, accumulate as proximal colluvium and alluvium or be conveyed through the drainage net. When colluvium and alluvium accumulate in proximal areas sedimentary structures may be preserved allowing the study of evolutionary processes. This paper is an attempt to apply micromorphological analysis to the study of the sedimentary structures preserved in gullied hillslopes of some southern Brazilian areas. The deposits are dated either in accordance to the supposed age of the gully incision, as estimated by aerial photographs, or by the record, in the field, of the depositional event. As a result, the age of the study deposits ranges from about 200 to 30 years, including fresh sediments just deposited one day before sampling. The paper stresses the relationship between macroscopic structures and micromorphological parametrical description, emphasizing interpretation of sedimentary structures as the result of variable overland flow rates on the gullied hillslopes.

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Investigation of Soil Erosion from Bare Steep Slopes of the Humid Tropic Philippines

Earth Interactions ◽

10.1175/ei121.1 ◽

2005 ◽

Vol 9 (5) ◽

pp. 1-30 ◽

Cited By ~ 9

Author(s):

A. L. Presbitero ◽

C. W. Rose ◽

B. Yu ◽

C. A. A. Ciesiolka ◽

K. J. Coughlan ◽

...

Keyword(s):

Soil Loss ◽

Overland Flow ◽

Soil Surface ◽

Infiltration Rate ◽

Bare Soil ◽

The Philippines ◽

Roughness Coefficient ◽

Storm Events ◽

State College ◽

Erosion Processes

Abstract At the Visayas State College of Agriculture (ViSCA) on the island of Leyte in the Philippines, hydrologic and soil-loss measurements were recorded for 32 erosion events over 3 yr on three 12-m-long bare soil plots with slopes of approximately 50%, 60%, and 70%. Measurements included rainfall and runoff rates at 1-min intervals, total soil lost per event from the plot, rill details when observed after an erosion event, and soil settling-velocity characteristics. Storm events are characterized by high rainfall rates but quite low rates of runoff, because of the consistently high infiltration rate of the stable clay soil (an Oxic Dystropept). Both observation and modeling indicated that overland flow is commonly so shallow that much of the soil surface is likely to be unsubmerged. For the 70% slope plot, half the events recorded mean sediment concentrations from 100 to 570 kg m−3. A somewhat constant hydrologic lag between rainfall and runoff is used to estimate a Manning’s roughness coefficient n of about 0.1 m−1/3 s, a value used to estimate velocity of overland flow. Possible effects of shallow flows and high sediment concentrations on existing erosion theory are investigated theoretically but are found to have only minor effects for the ViSCA dataset. A soil erodibility parameter β was evaluated for the data whenever rilling was recorded following an erosion event. The values of β indicate that, except for events with higher stream powers, other erosion processes in addition to overland flow could have contributed to soil loss from erosion plots in a significant number of events.

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