Appendix 2 - Vegetation Communities and Regional Ecosystems

5.2.11 Regional Ecosystem 3.2.5
Description: Acacia crassicarpa ± Syzygium suborbiculare ± Parinari nonda woodland. On
beach ridges.
Status: Not of Concern
Vegetation Communities: 6c, 5p, 6g, 14v, 14t, 14q, 16c(co),16d(co), 16b(co), 16g(co)
Reference Sites: 10 Quaternary Sites. (Includes MO118, NAQ9, NAQ6, FRQ2).
Acacia crassicarpa dominant communities are common on prograding coastal dune and beach
ridge systems, particularly on Muralug within the Inner Island Group. Vegetation communities
comprising RE3.2.5 are structurally and floristically variable, ranging from tall shrublands to low
open woodlands, often with a mix of associated shrubland and woodland species. Acacia
crassicarpa may form a sub-dominant component of some of the communities grouped under this
classification.
Vegetation Community 6c: The type example of this RE is VC6c, represented as RE3.2.5a in
the RE mapping, is common on prograding beach ridge complexes typically found on the west
coast of Muralug. The dominant canopy comprises Acacia crassicarpa which is generally
associated with a number of vine forest and woodland species such as Sterculia quadrifida,
Terminalia subacroptera, Syzygium suborbiculare, Parinari nonda, Cochlospermum gillivraei,
Neofabricia myrtifolia, Grevillea parallela, and Melaleuca viridiflora. The community typically
forms a low open woodland community with bare sand clearly visible between canopy trees on
account of the sparse ground cover. Due to the frequent, although repetitive change in edaphic
conditions across these dune sequences, these communities are commonly mapped as
components of coastal dune complexes, as has been applied with VC16b, VC16d and VC16g.
Vegetation Community 5p: Vegetation community 5p has been mapped wherever Corymbia
species, (generally Corymbia novoguinensis, Corymbia clarksoniana or less commonly C.
tessellaris), form prominent emergents or canopy components, represented as RE subtype 3.2.5b.
Typically, Corymbia components are sparse, scattered as sub-dominant or co-dominant
components of the canopy layer with species such as Parinari nonda, Sterculia quadrifida,
Acacia crassicarpa, Canarium australianum and Alphitonia excelsa otherwise typical of VC6c.
A Long-Fruited Bloodwood thought to be Corymbia polycarpa was collected on Muralug and
Horn Islands 5 . The community is represented in Photograph 34.
Vegetation Community 6g: The broad system of stabilised transgressive dunes to the southwest
of the Badu Island township host this relatively well-developed acacia dominant open forest
type. Canopy heights are may reach 28m in some locations although communities of much lower
stature (12-15m) are a more typical representation. Acacia crassicarpa dominates the canopy
with Asteromyrtus brassii forming a prominent co-dominant to sub-dominant canopy species. A
range of associated species including Melaleuca dealbata and Corymbia novoguinensis may be
scattered sparsely throughout the canopy structure. In some locations, Asteromyrtus brassii may
dominate the canopy although such areas are generally restricted. The predominant sub-canopy
comprises Asteromyrtus brassii, Acmena hemilampra subsp. hemilampra, and Lophostemon
suaveolens with characteristic species of the shrub layer including Astermomyrtus brassii,
Dodonaea polyandra, Endiandra glauca, Halfordia kendack, Exocarpos latifolius, Psydrax
banksii, Litsea glutinosa, Deplanchea tetraphylla, and Breynia oblongifolia. A dense low shrub/
groundcover layer of Lomandra banksii is a general feature of this community in association with
Alyxia spicata, Lithomyrtus obtusa, Shizaea dichotoma and Panicum sp. As with the majority of
acacia dominant communities, VC6g is indicative of past disturbance and may be a seral stage in
a successional sequence from shrubland to eucalypt woodland. Alternatively, the forest type may
be indicative of a severe fire scarring within a former eucalypt dominant community that is in a
5 (DGF9219+DJS, DGF9221+DJS)
3d Environmental – Torres Strait Regional Ecosystem Mapping Project – August 2008
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