Appendix 2 - Vegetation Communities and Regional Ecosystems

5.2.20 Regional Ecosystem 3.2.24
Description: Closed herbland of mixed graminoids and forbs. Occurs on exposed foredunes
Status: Of Concern
Vegetation Communities: 17d, 17j, 16a (co), 16b (co), 16h (co), 16k (co)
Reference Sites: 3 Secondary (YOS02, YOS13, YOS16), 1 Quaternary (TU8)
Regional Ecosystem 3.2.24 forms an almost universal cover on the majority of coastal foredune
communities sampled, although its best development is often associated with sand cay islands of
the eastern group, particularly on foredune communities where sand actively accumulates.
Vegetation Community 17j is the dominant component of this ecosystem forming an open to
closed grassland and forbland complex composed of species including Spinifex sericeus, Vigna
marina, Ipomoea pes-capre subsp. brasiliensis, Cassytha filiformis and a range of halophytic
forbs such as Sesuvium portulacastrum. Grasses including Mnesithea rottboellioides and
Heteropogon triticeus form a prominent ground cover where the community is mapped as
VC17d, although such grassland areas are often an indication of prior disturbance.
The representation of this RE as a homogenous ecosystem is rare due to the fine scale ecotonal
change across foredune systems evident in the majority of locations. This ecosystem typically
complexes with RE3.2.25 (VC14y) where it merges on the leaward side of dunes with low
shrubland. In such locations, the community is mapped as complex 16a. It also mixes with a
range of other ecosystems including RE3.2.2 and RE3.2.6 represented in the mapping as complex
types 16b and 16k. The RE provides an important rookery for sea turtles.
5.2.21 Regional Ecosystem 3.2.25
Photograph 53. Typical structure of
RE3.2.24 (VC17j) on Masig Island
(YOS2).
Description: Sparse herbland of mixed herbaceous species on foredunes and beach ridges.
Status: Of Concern
Vegetation Communities: 16i, 14y, 16a (co), 16j (co)
Reference Sites: 1 secondary (YOS4), 1 Quaternary (TU8)
Regional Ecosystem 3.2.25 is composed of VC16i and VC14y, forming low sparse shrublands
and shrublands respectively. The ecosystem generally occurs on foredune locations in
association with and immediately landward of RE3.2.24 (VC17j) often complexing with this
3d Environmental – Torres Strait Regional Ecosystem Mapping Project – August 2008
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