Appendix 2 - Vegetation Communities and Regional Ecosystems

5.5 Other Classifications
Areas Represented as R: Areas labelled R represent bare rock pavement formed on volcanic,
granitoid or basaltic lithologies. Such areas lack soil development in any form and are generally
found in exposed and precipitous locations, often at the base of coastal escarpments immediately
above the intertidal zone. These areas are typically devoid of vegetation due to extreme exposure
to both wind and salt spray, although stunted shrubs, herbs and grasses may occupy rock fractures
where some shelter is provided. Due to extremely steep terrain, these communities are likely to
be under-represented in the mapping with many areas obscured by steep slopes.
6.0 Spatial Extent of Regional Ecosystems
The spatial analysis of regional ecosystems presented in Table 11 below, which compares preclearing
extent with contemporary representation, enables the area of current vegetation cover to
be compared to the pre-clearing extent. Results indicate that 98.9% of remnant vegetation cover
remains. The most extensive loss of remnant vegetation cover is attributable to the following
RE’s.
• RE 3.7.1x1, a vine thicket type which is now restricted to narrow fragments adjacent to
roadsides on ironstone exposures on the northern shores of Saibai Island (0.4% remains
in remnant condition;
• RE 3.2.28, Evergreen notophyll vine forest on beach ridges on coral atolls, shingle cays
and sand cays (45.4% remaining). Heavily impacted on Aureed, Warraber, and Masig;
• RE 3.3.69, Melaleuca dealbata and Corymbia clarksoniana open forest on alluvial plains
restricted to Moa (47% remaining);
• RE 3.8.5, Semi deciduous and deciduous vine thicket restricted to Erub and Mer (58.8%
remaining). Heavily fragmented through past native gardening with significant areas
have been replaced by bamboo;
• RE 3.12.13, Corymbia nesophila ± C. hylandii subsp. peninsularis woodland on acid
volcanic hills, restricted to Thursday, Zuna and Muralug (66.7% remaining);
• RE 3.2.6, Casuarina equisetifolia woodland of coastal foredunes (67.5% remaining).
Heavily impacted community on foreshores in a number of island groups;
• RE 3.2.15, Melaleuca viridiflora, Neofabricia myrtifolia woodland on beach ridges
occurring on Badu, Horn and Muralug (77.1% remaining). Nearly all of the clearing of
this RE is associated with increased urbanization on Badu including clearing for airstrips
(old and new); and
• RE 3.3.57, Tussock grassland on coastal plains of Moa, Gebar and Muralug (77.5%
remaining). A fire disclimaz community that has been impacted by clearing on Moa
Island (St Pauls).
Table 11. Analysis of pre-clearing regional ecosystems in the Torres Strait Island region.
Regional
Ecosystem
Pre-clearing Area
(ha)
Area (2007 Coverage-ha) % Remaining
Land Zone 1- Estuarine muds and alluvium subject to saltwater incursion
3.1.1 17908.8 17886.3 99.8
3.1.2 4327.01 4326.62 99.8
3.1.4 20.02 20.02 100
3.1.5 346.11 341.74 98.7
3.1.6 3325.38 3319.27 99.8
3.1.7 954.12 953.13 99.9
3d Environmental – Torres Strait Regional Ecosystem Mapping Project – August 2008
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