Abstract
Rainfall-runoff data collected from bare plots (20-216 m2) at 1-min intervals were used to compare theperformance of the Green-Ampt infiltration model and a spatially variable infiltration model (SVIM). The two modelshave the same number of parameters. For 60 natural storm events from six sites in Australia and South-East Asiancountries, the average Nash-Sutcliffe model efficiency was 0.77 for the Green-Ampt model and 0.83 for the SVIM. At allsites, the SVIM consistently outperformed the Green-Ampt model when compared to runoff data at a range of timeintervals and storm events, including events of very long duration. A larger hydrologic lag is needed for the Green-Amptmodel to fit the measured hydrographs in comparison to the SVIM, suggesting that the Green-Ampt model tends tounderestimate the infiltration rate when rainfall intensity is high. Measured rainfall and runoff rates show a positiverelationship between rainfall intensity and infiltration rate. Considerable spatial variability in the infiltration capacity atthe plot scale is implied by this positive relationship. This spatial variability clearly needs to be accommodated ininfiltration models, and the SVIM represents a simple formulation of the infiltration rate as a function of rainfall intensityto address this spatial variability. SVIM parameters can be related to the Green-Ampt parameters, and they couldtherefore be estimated directly using soil properties.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
