Shrubland (Eremophila sturtii), western nsw




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MVG 17 - Other Shrublands



Shrubland (Eremophila sturtii), western NSW (Photo: B. Pellow)

Overview

  • Dominated by a broad range of shrub species that may include mixed species communities and mosaics of several communities that are not heathlands (MVG 18) or Acacia shrublands (MVG 16).

  • Dominated by woody plants branching at or near ground level and with a canopy height of 1 –10 m and projected foliage cover of up to 70%

  • Dominant genera include Allocasuarina, Banksia, Bursaria, Dodonaea, Eremophila, Grevillea, Kunzea and Duma.

  • May include regenerating stands of other MVG’s e.g. MVG 9 Melaleuca Forest and Woodland or MVG 14 Mallee Woodlands and Shrublands.

Facts and figures

Major Vegetation Group

MVG 17 - Other Shrublands

Major Vegetation Subgroups

(number of NVIS descriptions)

57. Lignum shrublands NSW, QLD, SA, VIC, WA (27)

49. Melaleuca shrublands NSW, NT, QLD, SA, TAS, VIC, WA (133)

32. Other shrublands ACT, NSW, NT, QLD, SA, TAS, VIC, WA(420)

Typical NVIS structural formations

Shrubland (tall, mid, low)

Open shrubland (tall, mid, low)



Sparse shrubland (tall, mid, low)

Number of IBRA regions

66

Most extensive in IBRA region

Est. pre-1750 and present: Muchison (WA)

Estimated pre-1750 extent (km2)

157 530

Present extent (km2)

123 464

Area protected (km2)

23 136



Lignum shrubland, Macquarie Marshes NSW (Photo: K. Brandis)

Structure and physiognomy

  • Composed of a canopy of low to tall shrubs with a height of 1 –10 m and projected foliage cover varying from less than 10% up to 70%.

  • Canopy density influences the structure of the ground layer.

  • Ground layer is highly variable depending on soil moisture and texture, potentially including sclerophyllous sedges and rushes to perennial and/or ephemeral forbs and graminoids.

Indicative flora

  • Dominant shrub species may belong to genera such as Allocasuarina, Banksia, Bursaria, Dodonaea, Duma, Eremophila, Grevillea, Kunzea, Leucopogon, Persoonia, Thryptomene, Neofabricia and Nitraria.

  • Three subgroups are described.

    • Lignum shrublands are dominated by Duma florulenta (formerly Muehlenbeckia). Other shrubs present may include species of Chenopodium, Acacia and Atriplex. Frequently present graminoids are Eragrostis sororia, Eragrostis speciosa, Eragrostis lacunaria, Fimbristylis dichotoma and species of Aristida Astrebla, Dactyloctenium, Digitaria and Enteropogon. Forbs include Marsilea drummondii, Waltheria indica, Alternanthera nodiflora, Atriplex semibaccata, Atriplex spongiosa, Euphorbia drummondii, Dissocarpus biflorus and Sphaeromorphaea littoralis (Keith 2004; Neldner et al. 2014).

    • Melaleuca shrublands include a wide variety of Melaleuca species as dominant in the canopy depending on site characteristics and climate. Shrublands associated with mallee and other semi-arid systems may dominated by Melaleuca brevifolia and Melaleuca uncinata. Brackish or semi-saline environments may include shrublands dominated by Melaleuca halmaturorum or Melaleuca ericifolia. Coastal shrublands include Melaleuca huegelii in south-western Australia or Melaeuca armillaris in south-eastern Australia. Mire systems (MVG 21) in Tasmania and other parts of south-eastern Australia include dense shrublands dominated by Melaleuca squarrosa with a ground layer of sedges and ferns.

    • Other shrublands that includes a broad range of shrub species such as Allocasuarina, Banksia, Bursaria, Dodonaea, Eremophila, Grevillea, Kunzea, Leucopogon, Persoonia, Thryptomene, Neofabricia and Nitraria.

Environment

  • Distributed across a very wide range of environmental conditions within semi-arid rangelands to temperate coastal areas in the south-east and western areas of Australia.

  • Lignum shrublands and wetlands occur on inland floodplains and within broad drainage channels (Keith 2004; Neldner et al. 2014).

  • Melaleuca shrublands occur in widely contrasting environments, mostly within the temperate climate zone. These include semi-arid sandplains, coastal sand dunes, subsaline wetlands and freshwater mires.

  • Other shrublands span a range of environments, mostly within semi-arid or arid climates.

Geography

  • Scattered widely, mainly across southern Australia, extending to subtropical latitudes in Queensland.

  • Lignum shrublands occur through semi-arid and arid regions of inland Australia.

  • Melaleuca shrublands occur mainly across temperate latitudes in the mallee regions, coastal fringe and mire landscapes of Western Australia, South Australia, Victoria, NSW and Tasmania.

  • Other shrublands are scattered through inland Australia and into tropical latitudes.

Change

  • Approximately 22% of the estimated pre-1750 extent cleared accounting for 3.4% of total clearing in Australia mainly as a result of pastoral activities.

  • Approximately 34 000 km2 cleared since European settlement, primarily in mallee regions and near the coast.

  • Changes in shrublands occupying semi-arid landscapes are driven by total grazing pressure, and changes to fire regimes.

  • Threats include regular or intense wildfires and grazing pressure.

Tenure

Other Shrublands occur largely on leasehold land and protected areas.



ACT:




New South Wales:

leasehold and freehold land

Northern Territory:

leasehold and freehold land

Queensland:

leasehold land, freehold land, protected areas, reserved crown land

South Australia:

protected areas, leasehold and freehold land

Tasmania:

leasehold land, protected areas, some other crown land, little scattered freehold land

Victoria:

protected areas

Western Australia:

protected areas, leasehold and freehold land, other crown land

Key values

  • Biodiversity including a large variety of species within the plant communities, particularly after seasonal rains.

  • Remnant populations of a wide range of vertebrate and invertebrate species.

  • Lignum shrublands provide breeding habitat for a wide range of birds and mammals, including some rare and endangered species.

List of key management issues

  • Total grazing pressure management.

  • Feral animal control.

  • Preventing further fragmentation of remnant of native vegetation.

  • Maintenance of appropriate fire regimes.

  • Weed control.

  • As with other rangeland areas there are public policy issues of stewardship and land capability to support use, especially on leasehold lands.

  • Ongoing investment in development of rangelands monitoring systems remains a priority will provide increased opportunities for efficiencies in pastoral management and nature conservation investments within this MVG.

References

Australian Surveying and Land Information Group (1990) Atlas of Australian Resources. Volume 6 Vegetation. AUSMAP, Department of Administrative Services, Canberra, 64pp. & 2 maps.

Beadle N.C.W. (1981) The Vegetation of Australia. Cambridge Univ. Press, Cambridge, 690pp.

Beard J.S., Beetson, G.R, Harvey J.M. Hopkins A.J.M and Shepherd D.P. (2013). The Vegetation of Western Australia at 1:3,000,000 Scale. Explanatory Memoir. Second Edition. Science Division, Department of Parks and Wildlife, Western Australia

Keith D. (2004) Ocean Shores to Desert Dunes. The native vegetation of New South Wales and the ACT. Department of Environment and Conservation (NSW), Hurstville.

National Land and Water Resources Audit (2001) Australian Native Vegetation Assessment 2001. National Land and Water Resources Audit, Canberra, 332pp.

Neldner, V.J., Niehus, R.E., Wilson, B.A., McDonald, W.J.F. and Ford, A.J. (2014). The Vegetation of Queensland. Descriptions of Broad Vegetation Groups. Version 1.1. Queensland Herbarium, Department of Science, Information Technology, Innovation and the Arts.

Data sources

Interim Biogeographic Regionalisation for Australia (IBRA), Version 6.1.

Land Tenure in Australia's Rangelands (1955 to 2000), National Land and Water Resources Audit.

National Vegetation Information System, Version 4.1.

1996/97 Land Use of Australia, Version 2.

Collaborative Australian Protected Areas Database – CAPAD 2004 – Terrestrial.



Notes

  • See the Introduction to the MVG fact sheets for further background on this series.



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