Changes in soil surface properties under simulated rainfall and the effect of surface roughness on runoff, infiltration and soil loss

A - Papers appearing in refereed journals

Bahddou, S., Otten, W., Whalley, W. R., Shin, H., El Gharous, M. and Rickson, R. J. 2023. Changes in soil surface properties under simulated rainfall and the effect of surface roughness on runoff, infiltration and soil loss. Geoderma. 431, p. 116341. https://doi.org/10.1016/j.geoderma.2023.116341

AuthorsBahddou, S., Otten, W., Whalley, W. R., Shin, H., El Gharous, M. and Rickson, R. J.
Abstract

Soil erosion by water is a result of detachment of particles or small aggregates from the soil surface followed by transport of the detached material. One of the elements that affects surface runoff and soil erosion is the soil surface roughness (SSR). Prior research reports that increasing SSR reduces generation of runoff and soil loss. In addition to that, it is widely reported that across-slope oriented roughness is better at controlling soil and water losses. However, to date there have been few studies into the effect of both magnitude and orientation of SSR on runoff, infiltration and soil erosion at the sub process level (i.e. by raindrop splash and overland flow), occurring simultaneously. In this study, the effects of up-down-slope oriented SSR (Treatment A), across-slope oriented SSR (Treatment B) and random SSR (Treatment C) were compared, along with a smooth surface (Treatment D). A moderate slope gradient of 10 %, a simulated rainfall intensity of 90 mm hr−1 and storm durations of 15 or 30 min were considered. The SSR was measured using the chain method, before and after the rainfall event. Images of the soil surface were taken using a hand-held laser scanner to monitor the effect of rainfall on the surface morphology. The outcome of this study shows that rainfall erosivity increases the SSR of the initially smooth surface, but decreases that of the initially rough surface, particularly in the random SSR treatment, where the decrease in SSR was 64 % of the pre-rainfall condition. This was due to the effects of raindrop impacts and overland flow. The random SSR treatment generated significantly more runoff and soil loss, and less infiltration than all other treatments (p < 0.001), but for raindrop splash erosion, there was no significant difference between random SSR and the other treatments. Contrary to expectations, the across-slope oriented SSR did not always reduce runoff and soil erosion compared to the up-down-slope orientation. This can be explained by degradation of surface microtopography by rainfall and runoff, as confirmed by the post-rainfall SSR measurements.

KeywordsSoil surface roughness; Raindrop impact; Runoff; Infilitration; Soil loss; Splash erosion
Year of Publication2023
JournalGeoderma
Journal citation431, p. 116341
Digital Object Identifier (DOI)https://doi.org/10.1016/j.geoderma.2023.116341
Open accessPublished as ‘gold’ (paid) open access
FunderBiotechnology and Biological Sciences Research Council
Funder project or codeS2N - Soil to Nutrition [ISPG]
Publisher's version
Output statusPublished
Publication dates
Online03 Feb 2023
Publication process dates
Accepted15 Jan 2023
PublisherElsevier Science Bv
ISSN0016-7061

Permalink - https://repository.rothamsted.ac.uk/item/98vy5/changes-in-soil-surface-properties-under-simulated-rainfall-and-the-effect-of-surface-roughness-on-runoff-infiltration-and-soil-loss

65 total views
27 total downloads
0 views this month
0 downloads this month
Download files as zip