HR: 0800h
AN: H21A-1307    [Abstracts]
TI: Transformation and Filtering Process of Lakes in A Catchment
AU: * Kusumastuti, D
EM: kusumast@cwr.uwa.edu.au
AF: Centre for Water Research, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009 Australia
AU: Reynolds, D
EM: reynolds@cwr.uwa.edu.au
AF: Centre for Water Research, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009 Australia
AU: Sivapalan, M
EM: sivapala@uiuc.edu
AF: Centre for Water as a Complex Environmental System (CWACES), Departments of Geography and of Civil & Environmental Engineering, University of Illinois at Urbana-Champaign , 220 Davenport Hall, MC-150, 607 South Mathews Avenue, Urbana, IL 61801 United States
AB: This study aims to gain a conceptual understanding of climate-landscape controls on the transformation process from rainfall to runoff on a single lake. A lake in a catchment may act as a source of threshold nonlinearities as the resulting storage effect has the tendency to attenuate or terminate runoff, and then suddenly release the water at times when the storage capacity is exceeded. A conceptual rainfall-runoff model is used in order to represent the hydrological processes in a catchment that consist of upland areas which drain into a shallow lake. Synthetic rainfall time series adapted to climatic conditions of Western Australia are used in the simulations. Given a ratio of the upland area to lake area, simulations have been done to identify the characteristics of the storms triggering lake overflows. The analysis of storm variabilities clearly shows that the storm domains triggering lake overflow are very different, and range from low to high storm depth, short to medium inter-storm period, short to medium duration, and medium to high intensity. This study also investigated the effect of soil depth in the upland areas on lake overflows. It is shown that the interaction between rainfall and soil depth leads to some triggering of excess flow from the catchment. As a result, the magnitude of lake flood events differs significantly from shallow to deep soils during high rainfall events. In general, the storm domains triggering lake overflow have similar range of storm variabilities from shallow to deep soils.
DE: 1804 Catchment
DE: 1850 Overland flow
SC: Hydrology [H]
MN: Fall Meeting 2005