Abstract
The soil's resistance to concentrated flow erosion is an important factor for predicting rill and (ephemeral) gully erosion rates. While it is often treated as a calibration parameter in process-based soil erosion models, global change studies require the estimation of erosion resistance from measurable soil properties. Several laboratory and field experiments have been conducted to determine the erosion resistance of various types of soils, but no attempts have been made hitherto to summarize all these data and to explore them for general trends. In this study, all available data on the resistance of topsoils to concentrated flow erosion in terms of channel erodibility (Kc) and critical shear stress ( τ cr) has been collected together with all soil and environmental properties reported in literature to affect the soil erosion resistance. Reported Kc values for cropland topsoils range between 0.002 10 − 3 s m − 1 and 250 10 − 3 s m − 1 ( n = 470), whereas τ cr values range between 0 and 15 Pa ( n = 522). It is demonstrated that so far, the heterogeneity of measurement methods, the lack of standardized definitions and the shortcomings of the flow shear stress model hamper the comparability of soil erosion resistance values from different datasets. Nevertheless, combining Kc and τ cr data from different datasets, a general soil erosion resistance ranking for different soil textures can be proposed. The compiled dataset also reveals that tillage practices clearly affect Kc (Kc for conventional tillage > Kc for reduced tillage > Kc for no tillage) but not τ cr. It was concluded that Kc and τ cr are not related to each other and that soil and macro-environmental properties affecting the foremost do not necessarily affect the latter as well and vise versa. Often Kc seems to be a more appropriate parameter than τ cr to represent the differences in soil erosion resistance under various soil and environmental conditions (e.g. bulk density, moisture content, consolidation, tillage). The two parameters represent different quantities and are therefore both needed to characterize the soil's resistance to concentrated flow erosion.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.