Distributed dynamic modelling of interrill overland flow

✍ Scribed by Anthony J. Parsons; John Wainwright; Athol D. Abrahams; J. Roger Simanton

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 546 KB
• Volume: 11
• Category: Article
• ISSN: 0885-6087
• DOI: 10.1002/(sici)1099-1085(199711)11:14<1833::aid-hyp499>3.0.co;2-7

✦ Synopsis

A distributed, dynamic, process-based model for interrill overland ¯ow that has previously been shown to predict accurately both total runo and runo hydraulics for a site on semi-arid shrubland is assessed in terms of (i) its portability, (ii) its sensitivity to the quality of data inputs, and (iii) its sensitivity to the size of cell used in the model. It is found that the model can be used at another site, but only after modi®cations to take account of the local controls of runo routing. The model is portable, but not readily so. The model is sensitive to both the quality of data input and the size of cell. Data input cannot be reduced by use of stochastic distribution of model parameters without signi®cant loss of accuracy in model predictions, particularly of runo hydraulics. Larger cells produce poorer predictions of the runo hydrograph. It is concluded that process-based modelling of interrill runo may not be a realistic tool for predicting soil erosion, but is one that may be useful for identi®cation of our present poor understanding of erosion processes. Such models help to de®ne the research agenda for soil erosion studies.