Underpinnings of fire management for biodiversity conservation in ...

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For completion, the concept of the buffer (Gill 1986) is introduced. A buffer is a fuel-reduced strip
designed to modify fire behaviour to enhance the chance of direct suppression success. This is not
a track in the sense that it is not scraped, bare earth is not created and vegetative regrowth may be
expected to begin immediately after its creation. Thus buffers have temporary value. Their usefulness
for fire suppression is likely to be greatest when they encompass tracks or fill the area between
parallel tracks (Plate 2.1). Buffers may be created by burning, slashing or other methods (see the
section on Track Widths, below).
Plate 2.1 Road and track networks: parallel tracks placed to enable between-track burning for the creation of a buffer strip on
the coastal plain north of Perth, Western Australia (Gill 1985).
Effects of tracks on the environment
Stating that tracks have no effect on the environment is a tautology because the act of their creation
is in itself an effect. The question, rather, is the extent to which their wider effects – compared with
merely causing a strip of bare soil – occur in different landscapes.
Tracks and roads have effects on the physical and biological environment and this attains greatest
significance in conservation areas. Coyne (2001) concluded, from a review of threats to animal species
in the Australian Alps’ National Parks, that ‘10 species were threatened by roads or road construction’.
Trombulak and Frissell (2000) detail a number of examples of road effects on populations of native
animals in the Northern Hemisphere. While this review is a useful general reference it has a strong
emphasis on the Northern Hemisphere, where effects due to road-salting practices, for example, may
be expected to have greater significance than in south-eastern Australia.
The effects of tracks include the following.
1. Tracks affect drainage, erosion and sedimentation. As Tromulak and Frissell (2000) state:
‘roads directly change the hydrology of slopes and stream channels’. These effects occur in three
main ways. The first is associated with keeping the tracks dry by mounding and compressing
them while creating spoon drains and mitre drains alongside. Consequently, these actions increase
local run-off and the channelling of water to areas not previously so endowed, thereby increasing
scouring capacity. The second is by the creation of blockages to the normal flow of cross-track
drainages, sometimes creating swamps and thus sinks for sediment. From time to time this may
divert drainage into new channels where scouring can occur. Finally, general erosion of unsealed
Fire and adaptive management Underpinnings of fire management for biodiversity conservation in reserves