HR: 10:50h
AN: H21G-03    [PDF]
TI: A Watershed Similarity Index for Characterizing Homogeneity in Storm Runoff due to Saturation Excess Overland Flow
AU: * Aryal, S K
EM: santosh.aryal@csiro.au
AF: CSIRO Land and Water, Private Bag No. 5, Wembley, WA 6913 Australia
AU: Bates, B C
EM: bryson.bates@csiro.au
AF: CSIRO Land and Water, Private Bag No. 5, Wembley, WA 6913 Australia
AU: Campbell, E P
EM: eddy.campbell@csiro.au
AF: CSIRO Mathematical and Information Sciences, Private Bag No. 5, Wembley, WA 6913 Australia
AB: A physically based, watershed similarity index is proposed for use in regionalization studies. The index is based on the steady state assumption and is applicable to watersheds where storm runoff is generated principally by the saturation excess (Dunne) mechanism. It uses variables that can be derived from readily available data for topographic, soil and climatic attributes. The method is applied to nine watersheds (4 to 83 km2) located in the state of Victoria, Australia. Finite mixture estimation is used to identify clusters of watersheds that group according to the similarity index. A three-component log-normal mixture model provides an adequate fit to the index distribution, suggesting the existence of three subpopulations. Comparisons with groupings indicated by hydrograph recession analysis, multifractal analysis of daily runoff, and a peak-over-threshold analysis of hourly discharge show reasonable agreement.
DE: 1821 Floods
DE: 1860 Runoff and streamflow
DE: 1866 Soil moisture
DE: 3250 Fractals and multifractals
SC: Hydrology [H]
MN: 2003 Fall Meeting