Predicting Factors Affecting Fire Behaviour in Heathland Vegetation

Australia has some of the most fire prone vegetation in the
world. Generally regarded as the most volatile fuels are heathlands
(shrublands) and sparse dry-sclerophyll eucalypt woodland with a
heath understorey. In these fuel types up to 80% of fuel burnt can
be live fuels.

The Sydney Sandstone Basin has vast areas of these vegetation
types close to its 6,500km of urban interface. Fires in heathland
and heathy woodland surrounding Sydney have caused millions of
dollars of damage and claimed the lives of a number of people.
Following the death of 4 National Parks and Wildlife Service staff
in Kuring-Gai-Chase National Park (Jun 2000) a key recommendation
of the State Coroner was that there be a burn guide formulated for
the Sydney Basin.

A prescribed burning guide is formulated by measuring fires in a
given vegetation type and modelling the relationship between the
Rate of Spread (ROS) and Dead Fine Fuel Moisture (FFM), Live Fine
Fuel Moisture (LFM), fuel characteristics, topography and wind
speed at the fire.

Project Overview

This 3 year project, initiated in January 2004, is focused on
fuel moisture and fuel availability of heath complexes &
woodland with a shrub component in the Sydney Sandstone Basin.
Field and laboratory data is being collected and will be used to
investigate, develop and test methods for predicting factors that
govern fire behaviour in these vegetation types, namely:

Dead fine fuel moisture (FFM) (<6mm diameter) - Examining
the behaviour of litter and elevated fuel hourly for several
diurnal cycles, including drying after rain.

Sub study – Lab based Equilibrium Moisture
Content (EMC).

Live fine fuel moisture (LFFM) (<3mm diameter) - Measuring
the live fine fuel moisture content of four common heath (shrub
species) and one sedge species fortnightly over two seasonal
cycles.
Seasonal changes in the live to dead ratio of sedges (grass
like vegetation).

Application of Results

PhD results will provide fire managers with;

More information on FFM drying after rain,
A better understanding of FFM behaviour under equilibrium
moisture content, conditions,
Improved knowledge on fuel availability,
An insight into LFFM behaviour.

Results will provide fire researchers with;