Flow-driven soil erosion processes and the size selectivity of sediment

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Author(s)
Asadi, H
Moussavi, A
Ghadiri, H
Rose, CW
Griffith University Author(s)
Year published
2011
Metadata
Show full item recordAbstract
The processes and mechanisms of entrainment and transportation of soil particles by surface runoff was investigated in the laboratory by a 0.05 נ0.2 נ3 m flume for two contrasting soil samples. The results show that there are at least two different mechanisms affecting particle transport by flow, with their relative importance relating to hydraulic condition, especially flow streampower. Different particle size classes are transported mainly by one mechanism. Suspension/saltation was observed to be the only mechanism at low streampowers (<0.1 W m-2). Bed load transport, probably involving rolling was shown to be activated ...
View more >The processes and mechanisms of entrainment and transportation of soil particles by surface runoff was investigated in the laboratory by a 0.05 נ0.2 נ3 m flume for two contrasting soil samples. The results show that there are at least two different mechanisms affecting particle transport by flow, with their relative importance relating to hydraulic condition, especially flow streampower. Different particle size classes are transported mainly by one mechanism. Suspension/saltation was observed to be the only mechanism at low streampowers (<0.1 W m-2). Bed load transport, probably involving rolling was shown to be activated at the streampowers greater than a specific threshold of about 0.1-0.15 W m-2, becoming the dominant transport mechanism at these modest streampowers. The relative importance of the two transport mechanisms was also related to soil types. Particle density seemed to have a main role in this context. Comparison with theoretical prediction of sediment concentration provided some support for the increasing dominance of bed load transport mechanisms with increasing streampower in these experiments
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View more >The processes and mechanisms of entrainment and transportation of soil particles by surface runoff was investigated in the laboratory by a 0.05 נ0.2 נ3 m flume for two contrasting soil samples. The results show that there are at least two different mechanisms affecting particle transport by flow, with their relative importance relating to hydraulic condition, especially flow streampower. Different particle size classes are transported mainly by one mechanism. Suspension/saltation was observed to be the only mechanism at low streampowers (<0.1 W m-2). Bed load transport, probably involving rolling was shown to be activated at the streampowers greater than a specific threshold of about 0.1-0.15 W m-2, becoming the dominant transport mechanism at these modest streampowers. The relative importance of the two transport mechanisms was also related to soil types. Particle density seemed to have a main role in this context. Comparison with theoretical prediction of sediment concentration provided some support for the increasing dominance of bed load transport mechanisms with increasing streampower in these experiments
View less >
Journal Title
Journal of Hydrology
Volume
406
Issue
1-2
Copyright Statement
© 2011 Elsevier B.V.. This is the author-manuscript version of this paper. Reproduced in accordance with the copyright policy of the publisher. Please refer to the journal's website for access to the definitive, published version.
Subject
Soil physics