Regional ecosystem details for 8.10.1
| Regional ecosystem | 8.10.1 |
|---|---|
| Vegetation Management Act class | Of concern |
| Wetlands | Not a Wetland |
| Biodiversity status | Of concern |
| Subregion | 4 |
| Estimated extent1 | Pre-clearing 300 ha; Remnant 2021 300 ha |
| Short description | Acacia julifera and/or Eucalyptus spp. +/- Corymbia spp. open forest and/or semi-evergreen, simple microphyll low closed forest and/or Heteropogon contortus tussock grassland on slopes of islands on Cretaceous sedimentary rocks |
| Structure code | Open Forest |
| Description | Acacia julifera subsp. julifera closed forest to woodland, or Corymbia dallachiana and/or C. tessellaris, and/or Eucalyptus exserta woodland to open forest (to low open forest). Also includes areas of semi-evergreen, simple microphyll low closed forest, and areas of Heteropogon contortus tussock grassland. Shrubs in woodland and open forest communities may include Wikstroemia indica, Seringia lanceolata, Acacia julifera subsp. julifera, Alphitonia excelsa, Geijera salicifolia, Planchonia careya, and pioneering rainforest species. A grassy to forb-rich ground layer often includes species such as Paspalidium distans, Heteropogon contortus, Digitaria brownii, Dinebra decipiens var. decipiens, Eragrostis spp. and Lomandra spp. Dominant species in patches of semi-evergreen closed forest include Ficus spp., Alectryon connatus, Brachychiton australis and Sersalisia sericea. Areas of open grassland are dominated by species such as Heteropogon contortus, Themeda triandra, Dichanthium sericeum and Aristida spp. Occurs on slopes of exposed gentle or flat ridge-crests and exposed rocky headlands on gently undulating rises to undulating low hills of lowlands on islands and headlands. Rock is sometimes present at the surface. Includes some areas of lithosols of weathered rock derived from this geology. Geology mapped as Kx (Styx Coal Measures). Early Cretaceous quartzose sandstone, green lithic sandstone, mudstone, conglomerate, carbonaceous shale and coal. Not a Wetland. (BVG1M: 28e). Vegetation communities in this regional ecosystem include: 8.10.1a: Acacia julifera subsp. julifera closed forest to low woodland. There may sometimes be emergents such as Eucalyptus exserta, Corymbia clarksoniana, or occasionally C. tessellaris. The relatively dense canopy often restricts most other shrubs, but occasional species may include Wikstroemia indica, and Seringia lanceolata. In the western parts of Wild Duck island, patches of Allocasuarina luehmannii replace Acacia julifera subsp. julifera, or they may intergrade. There is a grassy ground layer of Paspalidium distans, Eriachne rara, Eragrostis spp., Lomandra multiflora and Lomandra confertifolia. Occasional rainforest elements are present in areas that have remained unburnt, in particular Jasminum simplicifolium and Psychotria daphnoides. Occurs on exposed gentle or flat ridge-crests (often on headlands) on gently undulating rises to undulating low hills of lowlands. Rock is usually present at the surface. Includes some areas of lithosols of weathered rock derived from this geology. Geology mapped as Kx (Styx Coal Measures). Early Cretaceous quartzose sandstone, green lithic sandstone, mudstone, conglomerate, carbonaceous shale and coal. Not a Wetland. (BVG1M: 28e). 8.10.1b: Corymbia dallachiana and/or Corymbia tessellaris, and/or Eucalyptus exserta woodland to open forest (to low open forest). Other associated species in the canopy may include C. clarksoniana and occasionally E. platyphylla. A shrub layer may be present and may include species such as Acacia julifera subsp. julifera, Alphitonia excelsa, Geijera salicifolia, Planchonia careya, Phyllanthus novae-hollandiae and other Acacia spp. Pioneering rainforest trees, shrubs and vines may sometimes form a prominent secondary tree layer. In the western half of Wild Duck Island, a variation of this community is associated with soil soakages with localised clumps of Melaleuca nervosa and/or Melaleuca viridiflora var. viridiflora. A grassy to forb-rich ground layer may include Heteropogon contortus, Digitaria brownii, Dinebra decipiens var. decipiens, Sida hackettiana, Aristida spp., Eriachne rara, Setaria surgens, Urochloa foliosa, Oplismenus spp., Scleria mackaviensis, Cyperus gracilis, Eragrostis spp. and Gahnia aspera. Occurs on slopes on gently undulating rises to undulating low hills of lowlands on islands and headlands. Soils are grey or white sandy loams. Geology mapped as Kx (Styx Coal Measures). Early Cretaceous quartzose sandstone, green lithic sandstone, mudstone, conglomerate, carbonaceous shale and coal. Not a Wetland. (BVG1M: 9c). 8.10.1c: Semi-evergreen, simple microphyll to notophyll vine thicket to vine forest. On headlands, the structure is low and wind-sheared (2-4.5m), and the canopy is dominated by species such as Ficus spp., Alectryon connatus, Brachychiton australis, Sersalisia sericea, Exocarpos latifolius and Falcataria toona. In more protected areas along low steep sharp cliff-lines and minor sharp ridge-crests the structure is taller (up to 12m), and the canopy is dominated by Ficus obliqua, F. virens and F. rubiginosa forma rubiginosa. There is a lower tree layer with species including Falcataria toona, Alectryon connatus, Geijera salicifolia, Cryptocarya triplinervis and Terminalia porphyrocarpa. Vines are prominent and include Jasminum simplicifolium, Capparis sepiaria, Pandorea pandorana, Cissus oblonga and C. reniformis. Moister sandstone canyon floors support Polyalthia nitidissima, Alyxia ruscifolia, Acronychia laevis, Cyclophyllum coprosmoides, Hoya australis subsp. australis, Secamone elliptica and Drypetes deplanchei. Cliffs (often on headlands), ridges and crests on rolling rises to badlands, of the very dry rainfall zone, of lowlands and foothills, on Cretaceous quartzose sedimentary rocks on islands. Geology mapped as Kx (Styx Coal Measures). Early Cretaceous quartzose sandstone, green lithic sandstone, mudstone, conglomerate, carbonaceous shale and coal. Not a Wetland. (BVG1M: 5b). 8.10.1d: Heteropogon contortus tussock grassland with small areas of Themeda triandra. Associated species may include Dichanthium sericeum, Aristida spp., Cassytha pubescens, Oxalis perennans, Glycine tomentella, Scleria mackaviensis, Crotalaria montana and Phyllanthus spp. Small clumps of wind sheared rainforest species may be present, up to 1 metre in height. In minor areas, an unvegetated pavement of rock may predominate. In other minor seaward areas, an open woodland of Casuarina equisetifolia subsp. incana with isolated trees of Pandanus tectorius, occasional shrubs or vines of wind sheared Geijera salicifolia, Sersalisia sericea, Jasminum spp., and a grassy ground layer of Thuarea involuta, Sporobolus virginicus, or Heteropogon contortus may occur. Occurs on coastal exposed rocky headlands on Cretaceous quartzose sediments, subject to strong sea-breezes and salt-laden winds. Geology is mapped as Kx (Styx Coal Measures). Early Cretaceous quartzose sandstone, green lithic sandstone, mudstone, conglomerate, carbonaceous shale and coal. Not a Wetland. (BVG1M: 32b). |
| Protected areas | Broad Sound Islands NP, Broad Sound Islands Conservation Park |
| Special values | 8.10.1a: Significant due to the rarity of the geology type in the bioregion. The presence of Allocasuarina luehmannii is biogeographically significant and illustrates the connection between the islands' flora with that of sandstones within the adjacent Brigalow Belt Bioregion. 8.10.1b: Significant due to the rarity of the geology type in the bioregion. 8.10.1c: Habitat for near threatened plant species Xylosma ovata. 8.10.1d: A rare geology type in the Central Queensland Coast bioregion. This ecosystem most likely owes its existence to a combination of extreme windshear/salt-spray effects and a low surface rock content ensuring that it is not fire protected (Brennan 1986). It is therefore naturally restricted to exposed parts of islands and headlands. |
| Fire management guidelines | SEASON: Late wet to early dry season, with occasional storm burns (Nov-Dec). Winter burns may be acceptable if conditions have not been appropriate for burning until winter. c: not relevant. d: Anytime but avoid late winter to spring. INTENSITY: Mainly low, but with some moderate and high. c: not relevant. d: Low to moderate. INTERVAL: 3-7 years. c: not relevant. d: 4-6 years. INTERVAL_MIN: 3. INTERVAL_MAX: 7. STRATEGY: Apply mosaic burns across the landscape at a range of intervals. At a fine scale attempt to create a spatial mosaic with multiple burn patches 20 ha or less; aim for a 30-50% burnt area. At the bioregion scale do not burn more than 20% within the same year. c: Maintain surrounding fire-adapted communities with mosaic burning to minimise wildfire incursion. d: Burn when soils are moist. ISSUES: Lack of fire promotes overabundant pioneer rainforest species. Too frequent fire or inappropriately timed fire promotes weeds, including high-biomass grasses that lead to inappropriate fires. At least 7 years between burns is required to permit obligate seeding shrubs to reproduce. c: Will typically not burn. Heavily disturbed areas may potentially become flammable. |
| Comments | 8.10.1a: Occurs as c. 120 ha on Wild Duck Island. Has affinity with RE 8.12.29, but occurs on LZ 10. Distinguished from all other regional ecosystems and vegetation communities by the occurrence on Styx Coal measures (land zone 11) and dominance of Acacia julifera subsp. julifera. Thought to be restricted to Wild Duck Island, in the Broad Sound area. Possibly occurs on Outer Newry Island. Current known extent is approximately 90 hectares. 8.10.1b: Unit Ctc_11 has floristic affinities with RE 8.12.26 and 8.12.12d, but occurs on LZ 10. Distinguished from all other regional ecosystems and vegetation communities by the occurrence on Styx Coal measures (land zone 11) and dominance of Eucalyptus and or Corymbia spp. rather than Acacia julifera subsp. julifera. Restricted to Wild Duck Island and a small islet to the south-west called Infelix Islet, in the Broad Sound area. Possibly occurs on Outer Newry Island (Willmott 2006). In places, clumps of *Lantana camara are present, but are not dominant. Dieback of Corymbia dallachiana has been observed in recent years, which is probably a natural phenomenon caused by drought and periodic wildfire. Some other weeds are present, including *Melinis repens and *Sida cordifolia. 8.10.1c: This community has close floristic affinity with RE 8.12.11a and 8.11.11, but occurs on LZ 10. This is the only rainforest regional ecosystem on land zone 10. Thought to be restricted to Wild Duck Island, in the Broad Sound area. Probably minor areas on Outer Newry Island (Willmott 2006). Weeds appeared rare in this community, with *Lantana camara and *Solanum seaforthianum occasionally present. 8.10.1d: 8.10.1d belongs to the only RE so far described on land zone 10 in the Central Queensland Coast bioregion. The vegetation community 8.10.1d appears to be floristically similar to 8.12.13, and 8.11.9, but occurs on land zone 10. Thought to be restricted to Wild Duck Island, in the Broad Sound area. Possible minor occurrence on Outer Newry Island (Willmott 2006). Approximate extent is 60 hectares. Subject to severe invasion in some areas by *Melinis repens (Pollock 2007). Known to be subject to grazing pressure by introduced deer in 2007. |
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.
