Mitchell Grass Downs

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Mitchell Grass Downs
Mitchell grass downs post rain Boulia Shire Queensland P1070007.jpg
Mitchell Grass Downs in Boulia, Queensland
Ecoregion AA0707.png
Ecoregion territory (in purple)
Ecology
RealmAustralasian
Biometropical and subtropical grasslands, savannas, and shrublands
Borders
Geography
Area471,881 km2 (182,194 sq mi)
CountryAustralia
StatesNorthern Territory and Queensland
Coordinates22°24′S 141°36′E / 22.4°S 141.6°E / -22.4; 141.6Coordinates: 22°24′S 141°36′E / 22.4°S 141.6°E / -22.4; 141.6
Conservation
Conservation statusVulnerable
Protected11,486 km² (2%)[1]

The Mitchell Grass Downs is a tropical and subtropical grasslands, savannas, and shrublands ecoregion in northeastern Australia. It is a mostly treeless grassland, characterised by Mitchell grasses (Astrebla spp.).[2] [3] [4] [5][6]

Location and description[edit]

The ecoregion is bounded on the north and east by tropical savanna ecoregions – the Victoria Plains tropical savanna to the northeast, the Carpentaria tropical savanna to the north, the Einasleigh Uplands savanna to the northeast, and the Brigalow tropical savanna to the east. More arid ecoregions lie to west and south – the Great Sandy-Tanami desert to the southwest, the Simpson Desert to the south, and the Eastern Australia mulga shrublands to the southeast.[2]

The ecoregion includes three IBRA regionsMitchell Grass Downs, Mount Isa Inlier, and Desert Uplands.[2]

Climate[edit]

The climate is tropical and semi-arid. Average annual rainfall varies across the ecoregion, from 350 mm to 750 mm. In much of the ecoregion rainfall is seasonal, coinciding with the summer monsoon. Rainfall becomes less seasonal towards the southeast.[2]

Flora[edit]

The vegetation consists mostly of grasses along with wildflowers and low shrubs, including Queensland bluebush (Chenopodium auricomum). There are scattered dry acacia woodlands, predominantly of gidgee (Acacia cambagei). Watercourses support woodlands of red river gum (Eucalyptus camuldulensis), coolibah (E. coolabah), and paperbark (Melaleuca spp.).

The Desert Uplands has dry woodlands of Eucalyptus populnea, E. melanophloia, and E. similis. Low open woodlands of snappy gum (Eucalyptus leucophloia), Cloncurry box (E. leucophylla), and silver box (E. pruinosa) grow in the Mount Isa Inlier.[2]

External links[edit]

  • "Mitchell Grass Downs". Terrestrial Ecoregions. World Wildlife Fund.

References[edit]

  1. ^ Dinerstein, Eric; Olson, David; et al. (June 2017). "An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm". BioScience. 67 (6): 534–545. doi:10.1093/biosci/bix014. PMC 5451287. PMID 28608869.{{cite journal}}: CS1 maint: date and year (link) Supplemental material 2 table S1b.
  2. ^ a b c d e "Mitchell Grass Downs". Terrestrial Ecoregions. World Wildlife Fund.
  3. ^ "Map of Ecoregions 2017". Resolve. Retrieved 20 August 2021.
  4. ^ "Mitchell Grass Downs". Digital Observatory for Protected Areas. Retrieved 20 August 2021.
  5. ^ "Mitchell Grass Downs". The Encyclopedia of Earth. Retrieved 20 August 2021.
  6. ^ Stanton, J. P. (James Peter); Morgan, M. G; University of New England. School of Natural Resources (1977), The rapid selection and appraisal of key and endangered sites : the Queensland case study, the University of New England School of Natural Resources, pp. 1–10, retrieved 11 February 2022