Agriculture Reference
In-Depth Information
Fig. 8.4
Eucalyptus-
dominated woodland with charred trunks from previous fires on the eastern
margin of the MTC in western Victoria. (Photo by Jon Keeley.)
(Burrows & Friend
1998
; Gill & Catling
2002
; Burrows & Wardell-Johnson
2003
;
Yates
et al.
2003a
) and (3) is juxtaposed with contrasting communities, such as
rainforest relics (Bowman
2000
), dry grassy woodlands, chenopod shrublands and
hummock grass/shrublands (Beadle
1981
; Groves
1994
) on landscapes where
differential expression of fire plays a key role in determining landscape patterns.
As discussed later, MTV is also important because it forms the economic and
social backdrop to the most densely populated regions of the continent, with
attendant agricultural and natural-resource-based industries (e.g. forestry).
Eucalypts (collectively used to describe
Eucalyptus
,
Corymbia
and
Angophora
spp. within the Myrtaceae; Hill and Johnson
1995
) are a key component of
Australian MTV. Eucalypts form the dominant stratum in open woodlands and
forests and they are inevitably associated with fire (
Fig. 8.4
). They also dominate
certain shrublands and woodlands in multistemmed
mallee
(
Fig. 8.3
) and are a
variable component of other shrub-dominated plant communities such as heaths,
scrub-heaths and thickets (
Fig. 8.2b
). Even low-growing heathlands such as the
southwestern kwongan (Pate & Beard
1984
) contain varying proportions of
eucalypts in shrub or arborescent forms (Hopkins
et al.
1983
; Beard
1984
).
Communities not dominated by eucalypts are often azonal enclaves such as rock
outcrops, and wet heathlands within a matrix of vegetation containing a promin-
ent component of eucalypts.
MTV refers to woody evergreen sclerophyll plants that dominate systems, but
such taxa often occur in radically different ecosystems. For example, MTV often
forms an overstory in semi-arid and arid biomes composed of hummock grass-
lands and extensive chenopod shrublands (Beadle
1981
; Groves
1994
). Although
evergreen woody sclerophyll species are prominent, these represent very different