Regional ecosystem details for 8.1.3
Regional ecosystem | 8.1.3 |
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Vegetation Management Act class | Of concern |
Wetlands | Intertidal |
Biodiversity status | Of concern |
Subregion | 2, 5, 6, (1), (4) |
Estimated extent1 | Pre-clearing 5000 ha; Remnant 2021 4000 ha |
Short description | Sporobolus virginicus tussock grassland on marine sediments |
Structure code | Tussock Grassland |
Description | Sporobolus virginicus open tussock grassland to closed tussock grassland. Occasional emergents may include mangrove spp., Melaleuca spp., Acacia spp. and Clerodendrum inerme. Other ground layer species which may be present include Fimbristylis ferruginea, Cyperus victoriensis, C. scariosus, C. polystachyos var. polystachyos, Eleocharis spiralis, Diplachne fusca, Eriochloa procera, Fimbristylis polytrichoides, Gymnanthera oblonga. Ipomoea coptica, Epaltes australis, Paspalum vaginatum, Cyperus difformis, Cyperus javanicus, Sarcocornia spp. and Tecticornia spp. Occurs on supratidal flats adjacent to mangroves and saltpans (slightly more elevated than mangroves and saltpans). Often only inundated by highest spring tides and often dissected by small tidal channels. May be extensive where there are large areas of low-lying sediments. More often forms a narrow belt between mangroves and alluvial communities. Formed from Quaternary estuarine sediments with deep grey or black and grey saline cracking clays with occasional mottling, minor gilgai occasionally present. Geologies mapped include Qhe/m (Holocene mud, sandy mud, muddy sand and minor gravel), Qm (Quaternary coastal mud, silt and minor evaporites), Qpe (Pleistocene estuarine mud, sand), Qhcm (Holocene mud and sandy mud) and Qhe/s (Holocene sand, muddy sand, mud and minor gravel). Intertidal. (BVG1M: 35b). |
Supplementary description | Bailey et al. (2003), CMC-1; Batianoff, Dillewaard and Franks (1997), Vegetation Unit 7 (in part); Bean (1991), Vegetation type 9 - mangroves and saltpan (in part); Brushe et al. (in prep), Map Unit c103; Cumming (1997), Vegetation type 31; Nexus Environm |
Protected areas | Byfield NP, Sandringham Bay CP, Cape Palmerston NP, West Hill NP, Whitsunday Islands NP, Percy Isles NP, Cape Hillsborough NP, Bakers Creek CP |
Special values | 8.1.3: Many of the plant species defining this regional ecosystem are unique to it, or only to this and other land zone 1 regional ecosystems. Habitat for the threatened fauna species False Water Rat (Xeromys myoides) which is listed as "Vulnerable" in the Queensland Nature Conservation Act 1992. |
Fire management guidelines | INTERVAL: Fire return interval not relevant. INTERVAL_MIN: 100. INTERVAL_MAX: 100. ISSUES: Fire removes grassy habitat which may be used by the false water rat as cover from predators such as owls and the tawny frogmouth, hampering its movements. Fire can degrade habitat values including removal of food items for wader birds and other bird species. |
Comments | 8.1.3: Distinguished from all other vegetation communities by the clear dominance of Sporobolus virginicus. Occurs in mainland coastal areas throughout the bioregion. Also mapped on Whitsunday Island and Pine Peak Island (north of Percy Island). Best developed on the Goorganga Plains, Llewellyn Bay (just north of Cape Palmerston) and Corio Bay areas. Many smaller remnants outside the Goorganga Plains area are threatened by agricultural or urban development, heavy grazing, and ponded pastures. Also vulnerable to disturbance caused by vehicular use which quickly kills off the vegetation. Although relatively resistant to weed invasion, some species are able to take a hold, particularly *Cynodon dactylon, and also *Sporobolus jacquemontii, *Megathyrsus maximus, *Urena lobata, *Opuntia stricta and *Conyza spp. |
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.