There are many soil erosion models and model applications. However, as a general rule, models of rainfall erosion cannot fully model the complexity of the detachment and transport processes involved in soil erosion by rain so that it is crucial that soil erosion models are tested against experimental data. In developing the USLE, the designers recognised that the fundamental ability of a model to predict erosion in croplands began with its ability to account for soil losses from bare fallow areas under natural rainfall. Given this, any event-based model perceived to be a replacement for USLE-based models should be first tested for its ability to account for event soil losses from bare fallow areas under natural rain. Comparisons between the abilities of WEPP, RUSLE2 and the USLE-M to account for event soil loss on bare fallow runoff and soil loss plots leads to questions about the capacity of WEPP to model erosion on areas where some storms produce rills but others do not. One reason for this may lie in the fact that, in WEPP, sediment produced by raindrop-driven erosion is moved by flow-driven sediment transport to the outlet in situations where flow-driven sediment transport in channels does not occur. The modelling approach adopted by the designers of the USLE requires the veracity of any alternative erosion model to be established on bare fallow runoff and soil loss plots before focusing on erosion on vegetated areas.

中文翻译：

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WEPP 与基于 USLE 的模型比较：裸露休耕径流和土壤流失图的作用


土壤侵蚀模型和模型应用有很多。然而，作为一般规则，降雨侵蚀模型无法完全模拟雨水侵蚀土壤侵蚀所涉及的分离和传输过程的复杂性，因此根据实验数据测试土壤侵蚀模型至关重要。在开发 USLE 时，设计师认识到，模型预测农田侵蚀的基本能力始于它能够解释自然降雨下裸露休耕地区的土壤损失。鉴于此，任何被视为基于 USLE 的模型的基于事件的模型都应该首先测试其解释自然降雨下裸露休耕区的事件土壤损失的能力。WEPP、RUSLE2 和 USLE-M 在裸露休耕径流和土壤流失图上解释事件土壤流失的能力之间的比较导致了对 WEPP 在一些风暴产生溪流但其他风暴不产生的区域的侵蚀建模的能力的疑问。其中一个原因可能在于，在 WEPP 中，雨滴驱动的侵蚀产生的沉积物通过流动驱动的沉积物运输移动到出口，而河道中没有发生流动驱动的沉积物运输。USLE 设计者采用的建模方法要求在关注植被区域的侵蚀之前，在裸露的休耕径流和土壤流失地块上建立任何替代侵蚀模型的准确性。