On the storm flow response of upland Alpine catchments

✍ Scribed by Stefano Orlandini; Andrea Perotti; Giuseppe Sfondrini; Alberto Bianchi

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 308 KB
• Volume: 13
• Category: Article
• ISSN: 0885-6087
• DOI: 10.1002/(sici)1099-1085(199903)13:4<549::aid-hyp755>3.0.co;2-s

✦ Synopsis

Detailed measurements of near-surface soil hydraulic conductivity, K s , across the Bracciasco catchment (Central Italian Alps) are incorporated into a distributed, digital elevation model-based hydrological model to evaluate the eect of soil heterogeneity on catchment storm ¯ow response. Surface and subsurface storm ¯ow components are simulated for dierent distributions of K s , including that obtained directly from measurements, that obtained by averaging measured data and others obtained on the basis of a simple functional parameter model. The reproduction of the catchment storm ¯ow responses obtained using distributions of K s based on measurements is satisfactory although an adjustment of such distributions is suggested to reproduce the hydrograph peaks owing to rapid surface runo concentration and to improve the description of recession limbs at the same time. Numerical experiments indicate that the simulated storm ¯ow response of the study catchment is substantially insensitive to near-surface soil heterogeneity in as far as the predominant mechanism of channel storm ¯ow generation is subsurface ¯ow. However, K s is found to play an important role in the generation of overland ¯ow during intense rainfall and, under these circumstances, monitoring of near-surface heterogeneity may be important to provide accurate descriptions of both surface and subsurface storm ¯ow components.