Northern Uplands and Alluvial Plains (Environmental Region 8.1)
This region consists of five environmental associations. It occupies the north-western corner of South Australia and encompasses the rocky, easterly trending Mann and Musgrave Ranges and their immediate foreland of short alluvial fans, merging into extensive alluvial plains, both with deep red massive earths. Numerous granitic and gneissic inselbergs protrude through the plain which is locally overlain by sand dunes, particularly along the southern margin. The ranges and inselbergs are sparsely covered by hummock grasses (Triodia spp.), tufted grasses, such as mountain wanderrie (Eriachne mucronata), and occasional tall shrubs. Native fuchsia (Eremophila spp.), birdseye (Cassia spp.) and witchetty bush (Acacia kempeana) form a low open shrubland on the fans, and the plains carry a low woodland of mulga (A. aneura), needlebush (Hakea spp.) and rarely, desert oak (Casuarina decaisneana). The ranges provide panoramic views over fans and plains and form locally dominating background features in middleground panoramas from the plains. Watercourses fringes by woodlands also constitute local features in foreground to middleground panoramas. 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 is around 200 mm throughout and there is no distinct seasonal pattern. Temperatures show considerable diurnal and seasonal variation. Mean monthly evaporation reaches 450 mm in summer and falls to 150 mm in winter. Mean annual evaporation is about 3600 mm throughout the region.
