Key Laboratory of Ministry of Education on Land Resources Evaluation and Monitoring in Southwest China, Sichuan Normal University, Chengdu 610066, China.
Institute of Geography and Resources Science, Sichuan Normal University, Chengdu 610101, China.
Int J Environ Res Public Health. 2022 Jul 28;19(15):9213. doi: 10.3390/ijerph19159213.
Unpaved road erosion have been recognized as important sediment sources in a watershed. To evaluate where and when road erosion occurs, the soil loss along road segments should be precisely predicted with process-based erosion models. Methods: The hillslope version of the Water Erosion Prediction Project (WEPP) was used to estimate soil loss from 20 typical road segments in the red soil region of South China. Terrestrial laser scanning (TLS)-measured soil losses were used to validate the model simulations. The results showed that the WEPP model could reasonably predict the total soil loss in relatively short (less than 100 m) and gentle (slope gradient lower than 10%) road segments. In contrast, soil loss would be underestimated for long or steep road segments. Detailed outputs along roads revealed that most of the peak soil loss rates were underestimated. It might due to the linear critical shear stress theory in the WEPP model. Additionally, the lack of upstream flow was found to be connected to the relatively low model efficiency. Nevertheless, the WEPP simulation could accurately fit erosion trend and predict the peak soil loss positions along road segments. Conclusions: The WEPP model could be adopted to evaluate the erosion risk of unpaved roads in the red soil region of South China.
未铺砌道路侵蚀已被认为是流域内重要的泥沙来源。为了评估道路侵蚀发生的位置和时间，应使用基于过程的侵蚀模型精确预测道路段的土壤流失。方法：本研究采用坡面版的水蚀预测项目（WEPP）模型来估算华南红土区 20 个典型道路段的土壤流失。利用地面激光扫描（TLS）测量的土壤流失来验证模型模拟。结果表明，WEPP 模型可以合理地预测较短（小于 100 m）和较缓（坡度梯度低于 10%）道路段的总土壤流失。相比之下，长或陡的道路段的土壤流失会被低估。道路沿线的详细输出表明，大部分峰值土壤流失率被低估。这可能是由于 WEPP 模型中的线性临界剪切应力理论。此外，发现缺乏上游水流与模型效率相对较低有关。尽管如此，WEPP 模拟仍能准确拟合侵蚀趋势，并预测道路段的峰值土壤流失位置。结论：WEPP 模型可用于评估华南红土区未铺砌道路的侵蚀风险。
