How do root and soil characteristics affect the erosion-reducing potential of plant species?

Abstract

Plant roots can be very effective in stabilizing the soil against concentrated flow erosion. So far, most research on the erosion-reducing potential of plant roots was conducted on loamy soils. However susceptible to incisive erosion processes, at present, no research exists on the effectiveness of plant roots in reducing concentrated flow erosion rates in sandy soils. Therefore, the prime objective of this study was to assess the erosion-reducing potential of both fibrous and tap roots in sandy soils. Furthermore, we investigated potential effects of root diameter, soil texture and dry soil bulk density on the erosion-reducing potential of plant roots. Therefore, flume experiments conducted on sandy soils (this study) were compared with those on sandy loam and silt loam soils (using the same experimental set up). Results showed that plant roots were very efficient in reducing concentrated flow erosion rates in sandy soils compared to root-free bare soils. Furthermore, our results confirmed that fibrous roots were more effective compared to (thick) tap roots. Dry soil bulk density and soil texture also played a significant role. As they were both related to soil cohesion, the results of this study suggested that the effectiveness of plant roots in controlling concentrated flow erosion rates depended on the apparent soil cohesion. The nature of this soil type effect depended on the root-system type: fine root systems were most effective in non-cohesive soils while tap root systems were most effective in cohesive soils. For soils permeated with a given amount of fibrous roots, an increase of soil bulk density seemed to hamper the effectiveness of roots to

Soil erosion in the Anthropocene: Research needs

“…Similar to soil erodibility studies, research dealing with effects of plant roots on soil detachment rates has mainly focused on silt loam soils whereas these effects in sandy and clayey soils are less well understood (Vannoppen et al, 2015). For instance, Vannoppen et al, 2017 demonstrated that the erosion-reducing effects of fibrous and tap roots during concentrated runoff on sandy soils are different from those observed in loamy soils. In loose sandy soils, fibrous roots seem to be more effective in reducing erosion rates whereas tap roots seem to be much less effective as compared to the effects of these root properties in loamy soils.…”

Stability Analysis of Plant-Root-Reinforced Shallow Slopes along Mountainous Road Corridors Based on Numerical Modeling

“…The effect of root reinforcement increases the cohesive strength of soil, decreases soil deformation, prevents the incidence of surface tension cracks, and can avoid slope failure initiated by triggering factors [6][7][8][9][10][11][12][13][14][15][16]. The shear stress is developed in the soil and transferred to the ground as tensile resistance in the roots, which ensures mechanical reinforcement by the roots [17][18][19][20][21][22][23][24].…”

A review of the magnitude and response times for sediment yield reductions following the rehabilitation of gullied landscapes

“…[Colour figure can be viewed at wileyonlinelibrary.com] GULLY SEDIMENT YIELD REDUCTIONS FOLLOWING REHABILITATION the walls and floor) for maximum stabilization (Wilkinson et al, 2018). The functional attributes (such as root length, density and architecture) of the vegetation species, both above and below ground, are also important for facilitating infiltration and reducing runoff and erosion above and within gullies (Gyssels et al, 2002(Gyssels et al, , 2005De Baets et al, 2009;Stokes et al, 2014;Vannoppen et al, 2017).…”