Prediction of soil detachment rate by overland flow using root length characteristic: Nonlinear model development

Root length, as one of the most common characteristics of root, has an important role in controlling concentrated flow erosion. This study has explored the overall trends in reducing soil detachment rate as a function of the root length, based on the Hill curve model. In order to study the mechanical effects of root length on concentrated flow erosion rates, hydromulch was sprayed on soil surface and soil detachment rate was measured using a hydraulic flume. We found a nonlinear model for soil detachment rate as a function of root length (R2 = 0.81). Moreover, soil detachment rate was estimated well by the nonlinear models for ranges of flow shear stress (from 5.28 to 15.90 Pa) (p 0.75. These results can be used to predict the soil erosion resistance to overland flow using root length characteristic. •Hydromulch roots can be very effective in reducing soil detachment rate (SDR).•SDR decreased with increasing root length.•SDR was estimated well by an exponential regression relationship.•The root length had a positive effect on the rill erosion-reducing potential.