Regional ecosystem details for 4.5.3
| Regional ecosystem | 4.5.3 |
|---|---|
| Vegetation Management Act class | Least concern |
| Wetlands | Not a Wetland |
| Biodiversity status | No concern at present |
| Subregion | 1, 2, (1.3), (7), (1.1), (3) |
| Estimated extent1 | Pre-clearing 235000 ha; Remnant 2021 235000 ha |
| Short description | Acacia aneura, Triodia brizoides or Triodia molesta tall open shrubland on Tertiary sand sheets |
| Structure code | Tall Open Shrubland |
| Description | Acacia aneura tall open shrubland to open scrub. Scattered Acacia ligulata, Senna artemisioides subsp. helmsii and Senna artemisioides subsp. oligophylla shrubs occur frequently, and other Acacia spp., Cassia spp. and Eremophila spp. infrequently. The ground layer is dominated by hummock grasses, either Triodia brizoides or T. molesta. The ground cover hummocks are usually sparse, but the grasses Amphipogon caricinus and Aristida spp. may become prominent. The forb Euphorbia inappendiculata occurs frequently, and species from other families including Chenopodiaceae, Fabaceae and Malvaceae are present infrequently. Occurs on flat to gently undulating tops of dissected residual tablelands and associated plains. Soils shallow, gravelly red clays, gravelly red earths and loamy red earths. Lateritic gravel common on surface. Not a Wetland. (BVG1M: 23b). Vegetation communities in this regional ecosystem include: 4.5.3a: Acacia aneura and/or A. cambagei low open woodland. A variable shrub layer commonly occurs, including Senna spp., Eremophila spp. and Acacia spp. The ground layer is patchy with Triodia spp. and tussock grasses. Includes small areas of Senna spp. and Eremophila spp. low shrubland. Occurs on dissected, gravelly Tertiary sand sheets. Hard-setting red earth soils. Not a Wetland. (BVG1M: 23b). 4.5.3x1: Acacia aneura low woodland, commonly with Corymbia terminalis, Acacia spp., Atalaya hemiglauca, C. aparrerinja and Grevillea striata. The ground layer is sparse, including Triodia spp. and tussock grasses. Occurs on broad, residual Tertiary sand sheets. Deep red sands. Not a Wetland. (BVG1M: 23a). 4.5.3x1a: Acacia aneura low woodland, commonly with Corymbia terminalis, A. excelsa subsp. angusta, C. aparrerinja and Grevillea striata. The ground layer is patchy, including Triodia spp. and tussock grasses. Occurs on broad, residual Tertiary sand sheets. Deep red sands. Not a Wetland. (BVG1M: 23a). 4.5.3x1b: Acacia aneura tall open shrubland, commonly with A. georginae. Corymbia terminalis and Atalaya hemiglauca may occur in the canopy. The ground layer is sparse, with tussock and hummock grasses. Occurs on broad, residual Tertiary sand sheets, often overlying Cambrian limestones. Red sands. Not a Wetland. (BVG1M: 23a). 4.5.3x2: Eulalia aurea, Aristida sp. tussock grassland, commonly with annual grasses and forbs. Occurs on broad, Tertiary sand sheets. Red sands. Not a Wetland. (BVG1M: 30b). 4.5.3x70: Acacia aneura and/or A. cambagei low open woodland, occasionally with E. georginae. Emergent Corymbia terminalis may occur. A variable shrub layer may occur, including Senna spp., Eremophila spp. and Acacia spp. The ground layer is patchy with Triodia spp. and tussock grasses. Occurs on silcrete rises and lateritic plateau residuals derived from deeply weathered Cretaceous mudstones. Skeletal soils. Not a Wetland. (BVG1M: 23b). |
| Supplementary description | Mills (1980), M3; Wilson and Purdie (1990a), H1 (14); Neldner (1991), 24a (9). |
| Special values | 4.5.3: Potential habitat for threatened fauna species including night parrot Pezoporus occidentalis. |
| Fire management guidelines | SEASON: Wet to early dry season when soil is moist. INTENSITY: Low. INTERVAL: Broad interval range of 6-10 years for open acacia with grassy understorey. INTERVAL_MIN: 6. INTERVAL_MAX: 10. STRATEGY: Patchy, within the 20-30% range of area burnt. ISSUES: Acacias (e.g., mulga) germinate infrequently following high rainfall events, mature slowly and are long-lived. Acacias are vulnerable to frequent and high-severity fires. Fire in surrounding fire-adapted communities can be used to mitigate against wildfire. Fuel loads within Acacia communities can sometimes also require infrequent patchy burns, particularly following years of good rain, to protect them from wildfire and promote diversity at the ground layer. Long absence of fire can result in canopy closure by Acacias and lead to self-protection of these communities. Introduced invasive grasses (e.g., buffel Cenchrus ciliaris) may increase the risk and severity of fires. |
1 Estimated extent is from version 13.1 pre-clearing and 2021 remnant regional ecosystem mapping. Figures are rounded for simplicity. For more precise estimates, including breakdowns by tenure and other themes see remnant vegetation in Queensland.
