Applying physically based models that include preferential flow (PF) is still very challenging at the catchment scale. A gravity‐driven film flow approach could be a promising concept for modeling PF as it only requires a small number of parameters. We tested if this approach can be used for different soils and land covers within a 247 km² catchment and if we can find generalizable relationships of the film flow parameters to site or rainfall properties. We used a unique data set from a soil moisture sensor network with 135 instrumented soil profiles in three different geologies (slate, marl, and sandstone) and two land covers (forest and grassland) and fitted the film flow model to around 1,700 infiltration events. The results demonstrate that the physical relationship of film flow was capable to predict wetting front velocity (v) and flow parameters from rainfall input (q_s) alone. This relationship was pronounced in grassland sites but weaker for forest sites, probably due to heterogeneity of the rainfall input underneath the canopy. Incorporating the water content into the v‐q_s relationship did not improve the quality, but showed that for the film flow the rainfall input and hence gravity is in fact the dominant driver and not capillarity. Furthermore, abstraction of water into the soil matrix during film flow is an important process to be included into the framework with reasonable agreements for marl and sandstone using a multiple linear regression. Film flow and corresponding functional parameter relationships for other regions could improve catchment wide PF modeling in the future.

中文翻译：

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利用重力驱动的膜流模型预测集水区中不同土壤和土地覆盖物组合的入渗的潜力

在集水区范围内，采用包括优先流量（PF）在内的基于物理的模型仍然非常具有挑战性。重力驱动膜流方法可能是用于PF建模的有前途的概念，因为它仅需要少量参数。我们测试了这种方法是否可以用于247 km ²内的不同土壤和土地覆盖流域，如果我们能找到薄膜流量参数与场地或降雨特性的一般关系。我们使用了来自土壤湿度传感器网络的独特数据集，该数据集具有135种仪器测量的土壤剖面，分别位于三种不同的地质条件（板岩，泥灰岩和砂岩）和两个土地覆被（森林和草原）中，并将膜流模型拟合到大约1,700个入渗事件中。结果表明，膜流的物理关系能够单独预测降雨输入的湿锋速度（v）和流量参数（q _s）。这种关系在草原地区很明显，而在森林地区则较弱，这可能是由于冠层下降雨输入的异质性所致。结合水分进入v -q _s关系并没有改善质量，但表明对于膜流，降雨输入和重力实际上是主要驱动因素，而不是毛细作用。此外，在膜流动期间将水提取到土壤基质中是重要的过程，要使用多元线性回归将水灰和砂岩的合理协议纳入框架。未来其他地区的膜流量和相应的功能参数关系可能会改善集水区的PF建模。