<abstract xmlns="http://www.w3.org/1999/xhtml">The Three Gorges Reservoir region suffers from severe soil erosion that leads to serious soil degradation and eutrophication. Interrill erosion models are commonly used in developing soil erosion control measures. Laboratory simulation experiments were conducted to investigate the relationship between interrill erosion rate and three commonly hydraulic parameters (flow velocity <italic>V</italic>, shear stress <italic>τ</italic> and stream power <italic>W</italic>). The slope gradients ranged from 17.6% to 36.4%, and the rainfall intensities varied from 0.6 to 2.54 mm·min−1.The results showed that surface runoff volume and soil loss rates varied greatly with the change of slope and rainfall intensity. Surface runoff accounted for 67.2–85.4% of the precipitation on average. Soil loss rates increased with increases of rainfall intensity and slope gradient, Regression analysis showed that interrill erosion rate could be calculated by a linear function of <italic>V</italic> and <italic>W</italic>. Predictions based on <italic>V</italic> (<italic>R</italic>2 = 0.843, <italic>ME</italic> = 0.843) and <italic>W</italic> (<italic>R</italic>2 = 0.862, <italic>ME</italic> = 0.862) were powerful. <italic>τ</italic> (<italic>R</italic>2 = 0.721, <italic>ME</italic> = 0.721) did not seem to be a good predictor for interrill erosion rates. Five ordinarily interrill erosion models were analyzed, the accuracy of the models in predicting soil loss rate was: Model 3 (<italic>ME</italic> = 0.977) > Model 4 (<italic>ME</italic> = 0.966) > Model 5 (<italic>ME</italic> = 0.963) > Model 2 (<italic>ME</italic> = 0.923) > Model 1 (<italic>ME</italic> = 0.852). The interrill erodibility used in the model 3 (WEPP) was calculated as 0.332×106 kg·s·m−4. The results can improve the precision of interrill erosion estimation on purple soil slopes in the Three Gorges Reservoir area.</abstract>

The Three Gorges Reservoir region suffers from severe soil erosion that leads to serious soil degradation and eutrophication. Interrill erosion models are commonly used in developing soil erosion control measures. Laboratory simulation experiments were conducted to investigate the relationship between interrill erosion rate and three commonly hydraulic parameters (flow velocity V, shear stress τ and stream power W). The slope gradients ranged from 17.6% to 36.4%, and the rainfall intensities varied from 0.6 to 2.54 mm·min−1.The results showed that surface runoff volume and soil loss rates varied greatly with the change of slope and rainfall intensity. Surface runoff accounted for 67.2–85.4% of the precipitation on average. Soil loss rates increased with increases of rainfall intensity and slope gradient, Regression analysis showed that interrill erosion rate could be calculated by a linear function of V and W. Predictions based on V (R2 = 0.843, ME = 0.843) and W (R2 = 0.862, ME = 0.862) were powerful. τ (R2 = 0.721, ME = 0.721) did not seem to be a good predictor for interrill erosion rates. Five ordinarily interrill erosion models were analyzed, the accuracy of the models in predicting soil loss rate was: Model 3 (ME = 0.977) > Model 4 (ME = 0.966) > Model 5 (ME = 0.963) > Model 2 (ME = 0.923) > Model 1 (ME = 0.852). The interrill erodibility used in the model 3 (WEPP) was calculated as 0.332×106 kg·s·m−4. The results can improve the precision of interrill erosion estimation on purple soil slopes in the Three Gorges Reservoir area.

Equations for predicting interrill erosion on steep slopes in the Three Gorges Reservoir, China

Department of Soil and Water Conservation, Changjiang River Scientific Research Institute

School of Water Resources and Hydropower Engineering of Wuhan University

Journal of Hydrology and Hydromechanics

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The Three Gorges Reservoir region suffers from severe soil erosion that leads to serious soil degradation and eutrophication. Interrill erosion models are...

Equations for predicting interrill erosion on steep slopes in the Three Gorges Reservoir, China

Published Online: Feb 13, 2020

Page range: 51 - 59

Received: Jun 25, 2018

Accepted: Mar 10, 2019

DOI: https://doi.org/10.2478/johh-2019-0024

Keywords
Purple soil, Interrill erosion rate, Rainfall intensity, Slope gradient, Hydraulic parameter

© 2020 Qian Feng et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Equations for predicting interrill erosion on steep slopes in the Three Gorges Reservoir, China

Published Online: Feb 13, 2020

Page range: 51 - 59

Received: Jun 25, 2018

Accepted: Mar 10, 2019

DOI: https://doi.org/10.2478/johh-2019-0024

KeywordsPurple soil, Interrill erosion rate, Rainfall intensity, Slope gradient, Hydraulic parameter

© 2020 Qian Feng et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
Purple soil, Interrill erosion rate, Rainfall intensity, Slope gradient, Hydraulic parameter