Appendix D Terrestrial and Aquatic Biodiversity - Environment ...

4.2 Land Systems
Seven land systems fall within the MLA areas, however only three are located in the proposed mining zones,
including the Bukalara (Asb), Frog (Taf), and McArthur (Tam) land systems (Figure 12). More detailed
descriptions of land systems are provided in Chapter 3 of the EIS document.
4.3 Vegetation Surveys
4.3.1 Summary of Vegetation Types
Geology, landform and soils have a dominant influence in shaping the vegetation types present. Broadly,
five broadly defined vegetation types dominate the MLA areas, and these correlate with five main land forms
(described below and in Table 9).
Acacia Woodlands (Group A): Lancewood (Acacia shirleyi) open forest is found in fire shadow areas
adjacent to Melaleuca swamps or at the base of low hills. Acacia shirleyi and Callitris intratropica and may
also be found scattered within or around the edge of some vegetation types, most notably vegetation type 5.
Eucalyptus/Corymbia Woodlands over Hummock Grass (Group B): The well-drained rocky ridges,
stony rises, and slight slopes adjoining these rocky areas (with well drained and sandier soils) are dominated
by Corymbia and Eucalyptus woodland. In the northern part of the lease this woodland type the understorey
is dominated by Triodia species or is a mosaic of either a Hummock grass or Tussock grass, whereas in the
southern part of the lease the understory is dominated by heath (e.g. Bossea and Jacksonia species).
Woodlands on the slight slopes transition into the other major habitat type Melaleuca open woodland.
Eucalyptus/Corymbia Woodlands over Tussock Grass (Group C): Some small areas of Eucalyptus
tectifica and E. pruinosa open woodlands are patchily distributed on higher clay content soils usually not too
distant from the rocky rises. Eucalyptus pruinosa may often be present in an eco-tone between upland
Eucalyptus woodland and Melaleuca citrolens open woodland and in some case may be found within
expanses of Melaleuca citrolens vegetation types. Occasional heavy clay areas amongst the Melaleuca
plain support Excoecaria parvifolia woodlands with a distinct heavy clay soil flora.
Melaleuca Woodlands (Group D): The Melaleuca open woodlands occupy large parts of the MLA areas.
The frequency and length of inundation varies as does the clay content of the soil. Melaleuca citrolens tend
to occupy the sites with a greater clay content and for the most part drier or less inundated sites. Melaleuca
viridiflora occupies both sandier dry sites as well as wetter sites including billabongs and swamps.
Wetlands and Riparian Woodlands (Group E): The diffuse drainage system of the Towns Creek dissects
the main mine lease area and features floodplain, major and minor creek-lines as well as billabongs and
wetlands. Asteromyrtus symphyocarpa is most common in vegetation types associated with these systems
while Melaleuca viridiflora is also abundant. Eucalyptus and Corymbia are generally sparse and scattered
within these land forms but feature Corymbia polycarpa in the areas transitioning into a drier landform. Also
within these drainage areas Eucalyptus microtheca occurs on some of the more clayey floodplains and minor
creek-lines and on the outer edge of wetlands. Eucalyptus camaldulensis is common along the major creeklines
but either scattered to absent throughout the other drainage areas.
A total of 20 distinct vegetation units exist within the MLA areas (refer to Table 10 and Figure 14). Detailed
descriptions are provided in Appendix D-9.
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Doc Title: Appendix D – Terrestrial Biodiversity Technical Report