Splash erosion affected by initial soil moisture and surface conditions under simulated rainfall

Type of content
Journal Article
Thesis discipline
Degree name
Publisher
Elsevier BV
Journal Title
Journal ISSN
Volume Title
Language
en
Date
2021
Authors
Zambon N
Johannsen LL
Strauss P
Dostal T
Zumr D
Cochrane TA
Klik A
Abstract

Soil erosion by water is one of the most severe soil degradation processes. Splash erosion is the initial stage of soil erosion by water, resulting from the destructive force of rain drops acting on soil surface aggregates. Apart from rainfall properties, constant soil physical properties (texture and soil organic matter) are crucial in understanding the splash erosion. However, there is lack of information about the effect of variable soil properties such as soil initial water content and surface condition (seal formation) on splash erosion. The objective of the present study was to determine how initial water content and surface condition affected soil splash erosion under simulated rainfall. The changes in soil surface condition were characterized by hydraulic variability (saturated hydraulic conductivity) due to surface seal formation. Slit loam and loamy sand soil textures were used in the experiment. The soil samples were collected from the top layer; air dried, and filled into modified Morgan splash cups for splash erosion measurements. Rainfall was created in the laboratory using two types of rainfall simulators covering intensity range from 28 to 54 mm h−1 and from 35 to 81 mm h−1. The soil samples were exposed to three consecutive rainfall simulations with different time intervals between simulations and different initial water content and surface conditions (air-dried, wet-sealed, and dry-crusted). Wet-sealed soil samples had up to 70% lower splash erosion rate compared to air-dried samples, due to surface ponding followed by seal formation. A significant decrease in soil saturated hydraulic conductivity indicated the formation of surface seal for silt loam soils. A non-significant decrease in saturated hydraulic conductivity for loamy sand soil was attributed to earlier formation of stable seals. Two different rainfall simulators produced different amount of splash erosion rates; however, the splash erosion development for increasing rainfall intensity was almost equal considering same initial surface condition. These results provide insight into dynamic changes of individual soil parameters affected by rainfall, and could find wider application for more complex soil erosion prediction models.

Description
Citation
Zambon N, Johannsen LL, Strauss P, Dostal T, Zumr D, Cochrane TA, Klik A (2021). Splash erosion affected by initial soil moisture and surface conditions under simulated rainfall. CATENA. 196. 104827-104827.
Keywords
Splash erosion, Rainfall kinetic energy, Rainfall simulator, Saturated hydraulic conductivity, Surface sealing, Ponding
Ngā upoko tukutuku/Māori subject headings
ANZSRC fields of research
0403 Geology
0406 Physical Geography and Environmental Geoscience
0503 Soil Sciences
Fields of Research::40 - Engineering::4005 - Civil engineering::400502 - Civil geotechnical engineering
Fields of Research::41 - Environmental sciences::4106 - Soil sciences::410605 - Soil physics
Rights
© 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/BY/4.0/).