Central Tablelands (Environmental Region 8.3)
This region consists of 28 environmental associations. It extends from the dune country of the Great Victoria Desert to a chain of large salinas formed by Lakes Eyre, Gregory, Blanche, Callabonna and Torrens. The two main landform units are the stony silcrete tablelands and the lower-lying gibber and gypsum plains with duplex soils or calcareous earths. Along the margins of the Flinders Ranges alluvial fans with deep duplex soils occur. The sparse vegetation of the tablelands is dominated by bindyi (Bassia spp.) and bladder saltbush (Atriplex vesicaria). Shortlived tufted grasses such as Mitchell grass (Astrebla pectinata), blackheads (Enneapogon spp.) and kerosene grass (Aristida contorta) are associated with these chenopods. The gibber plains and alluvial fans are also dominated by sparse chenopod shrublands. Besides the bladder saltbush, pearlbush (Maireana astrotricha), cottonbush (M. aphylla) and spiny saltbush (Rhagodia parabolica) are common in the south, and silver saltbush (Atriplex rhagodioides) is characteristic although not dominant further north. Floodplains carry a fringing woodland of eucalyptus and acacias, old man saltbush (Atriplex nummularia) shrublands or perennial tussock grasslands of windmill grass (Enteropogen acicularis) and silky browntop (Eulalia fulva). In the south-east the Flinders Ranges (Province 6) are prominent background features in foreground to middleground panoramas which are escarpments, woodlands fringing floodplains and channels, and occasional dunes. The climate is warm to hot in summer and cool to cold in winter, with extremely low and unreliable rainfall and very high evaporation throughout the year. Mean annual rainfall generally varies between 125 and 500 mm in summer and falls to 150 mm in winter at Oodnadatta in the north. Mean annual evaporation ranges from 3100 mm in the south to around 4000 mm in the north.
