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Evan Webster
Role: 
PhD candidate
Contact details:
Phone: 
+61 2 9385 2817
Office: 
Level 5 East
Biological Sciences South (E26)

UNSW, Kensington 2052

Defining the spatio-temporal effect of vegetation, disturbance and rainfall in water catchment areas


Intense wildfire regimes are prevalent within many Australian water catchment areas and the quantification of the complex relationship between forests, wildfire events and catchment yield is an important consideration for catchment managers. Seasonal, temperature and precipitation induced changes to vegetation condition further complicate the underlying trends in these relationships. Within Sydney’s catchment areas, the post wildfire hydrological impact of the 2001/02 wildfires has been investigated from a catchment streamflow perspective, with modelling performed using streamflow and radar rainfall data collated for the Nattai River catchment area. However, results show no discernable impact on surface runoff at the large catchment scale. This research looked deeper, investigating internal catchment variability through the development and analysis of evapotranspiration maps, modelled with respect to drivers of catchment water use (wildfire recency, rainfall, solar radiation, temperature and wind speed). By implementing an adaptive spatial model, we simulated a Kuczera function response to wildfire induced changes of catchment water use for individual land units (30m by 30m Landsat pixels). We summarise and present the modelled impact of wildfire spatially with respect to vegetation structure, topography, geology and fire severity.

Supervisors:

Professor Richard Kingsford

Dr Dan Ramp (UTS)