Forests and Water
|
|
Research Theme: Post-fire Hydrology in a Changing Environment
The fire cycle, vegetation community and hydrologic cycle are intimately linked. The vegetation patterns we see today are the result of the fire regimes from our recent past. Vegetation communities have distinctive water-use signatures, determining streamflows from catchments for many decades after fire. These communities also offer protection from soil erosion and enhancement of water quality, to differing degrees depending on the frequency and magnitude of their characteristic fire events. These complex interactions and feedbacks between fire, vegetation, and water within our catchments provide us with a quantity and quality of potable water that we have assumed will continue into the future in a manner comparable to the past.
However, the last decade has seen a dramatic rise the occurrence of wildfire across the globe, from Australia, USA, Spain, Portugal, Canada and Greece. At a local level, climate change projections for SE Australia are for an increase in both extreme fire-weather and possibly extreme rainfall events. With more than 2 million ha of Victorian forest burnt by 3 major wildfires in the last 6 years, and a three-fold increase in the fuel reduction burn quota from 2008, fire is becoming an increasingly dominant component of our catchment management.
How will these changes affect streamflows, soil erosion, and water quality? How do we adapt our catchment and water resource management to a changing environment? These questions form the basis of a suite of ongoing research projects by the Forest and Water group in the Department of Forest and Ecosystem Science.
Left photo: PhD student Jane Cawson using rainfall simulation to investigate the effects of the “patchiness” of fire on runoff and erosion connectivity in forests.
Centre photo: Masters student Philip Noske erects a weather station to monitor meteorological conditions driving soil erosion events in a forest burnt on Black Saturday, Febuary 2009.
Right photo: PhD student Petter Nyman investigating a form of extreme post fire erosion event called debris flows in the Licola area following the 2007 Great Divide Fire.
Current projects
- East Kiewa study – Dynamics of runoff, sediment and nutrient fluxes from burnt forested catchments
- Post fire hillslope processes generating extreme erosion events in SE Australia
- Parameterising erosion and water quality models for burnt dry Eucalyptus Species forests in SE Australia
- Post-fire salvage harvesting effects on erosion processes, streamflow and water quality: measurement and modelling
- Prescribed fire effects on water quality in south-east Australian native forests
- The impact of bushfire on catchment processes and the potability of downstream water supplies
- The effect of two wildfires of different intensities and burn patterns on the water quality from a large forested catchment.
- Wildfire and water quality in water supply catchments
- Wildfire and Water Security Project: Modelling risks to water quality