Regional ecosystem details for 4.9.16
| Regional ecosystem | 4.9.16 |
|---|---|
| Vegetation Management Act class | Least concern |
| Wetlands | Not a Wetland |
| Biodiversity status | No concern at present |
| Subregion | 3, 4, 5, 2, (5.4), (6.9), (1.3), (5.5), (2.8) |
| Estimated extent1 | Pre-clearing 270000 ha; Remnant 2021 242000 ha |
| Short description | Acacia cambagei +/- scattered shrub species including Santalum lanceolatum and Eremophila mitchellii tall shrubland |
| Structure code | Tall Shrubland |
| Description | Acacia cambagei tall shrubland to low open woodland. Flindersia maculosa and Santalum lanceolatum are frequently present in the canopy. A lower shrub stratum may occur and is dominated by either A. cambagei and/or Senna artemisioides subsp. oligophylla, with scattered Carissa lanceolata, Enchylaena tomentosa, Eremophila latrobei and E. mitchellii shrubs occurring frequently. The ground stratum is dominated by the perennial grass Enteropogon acicularis, with Bothriochloa ewartiana and Chrysopogon fallax locally prominent, and Eragrostis xerophila and the shorter-lived Aristida latifolia present frequently. Sporobolus actinocladus and other ephemerals may be seasonally abundant. A variety of forbs, including Abutilon spp. and Sida spp. occur infrequently although the ephemerals may become seasonally prominent. Occurs on Cretaceous sediments with mantled pediments derived by erosion of Tertiary land surface. Landform typically low hills and associated undulating plains with slopes between 1-3%. Soils Shallow to deep, red clays and texture contrast soils overlying weathered rock. Red cracking clays often occur adjacent to this unit. The gravely clays are crusted and the texture contrast soils have hard setting surfaces with a structured clay subsoil. Soils are slightly acid to neutral but may be moderately alkaline at depth. Not a Wetland. (BVG1M: 26a). Vegetation communities in this regional ecosystem include: 4.9.16a: Acacia cambagei low woodland to low open forest, occasionally with Atalaya hemiglauca and Acacia aneura. A lower shrub layer of Acacia cambagei commonly occurs. The ground layer is sparse tussock grasses. Occurs on mantled pediments surrounding Tertiary lateritic plateaus derived from deeply weathered Mesozoic sediments. Stripped red-brown clays with surface gravel lag. Not a Wetland. (BVG1M: 26a). 4.9.16x40: Acacia cambagei low woodland to low open forest, occasionally with Atalaya hemiglauca. A shrub layer of Acacia cambagei commonly occurs. The ground layer is sparse tussock grasses and forbs. Occurs on undulating deposits of old alluvial and outwash clay materials overlying Cretaceous mudstones. primarily around the Kynuna Plateau subregion. Red-brown clays with surface gravel and cobble. Not a Wetland. (BVG1M: 26a). |
| Supplementary description | Mills (1980), G2 (LU 40, 41), G3 (LU 42); Neldner (1991), 26e (18); Turner et al. (1993), G3 (LU 10, 66); Wilson and Purdie (1990a), T1 (LU 37) |
| Protected areas | Lochern NP, Welford NP, Lark Quarry CP |
| Special values | 4.9.16: High fauna diversity compared to surrounding grasslands. |
| 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., gidgee) 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. |
| Comments | 4.9.16: This was listed in Sattler and Williams under 4.7.5 but has been reallocated to the correct land zone. Extensive areas of this regional ecosystem are regenerating in dense stands of young seedlings, from the 1950's and the 1970's, with an overstorey of older, often dead, trees (Fensham and Fairfax, 2004). Clearing is occurring. Major threats include further clearing and the associated fragmentation and introduction of exotic pasture species. 4.9.16x40: Previously mapped as 4.9.16 or 4.9.16a. x40 code denotes change of land zone (land zone 4). |
1 Estimated extent is from version 13 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.
