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Uluru is an inselberg shaped in arkosic sandstone located in the arid plains of central Australia. The indigenous people believed it rose out of a sand hill and has since remained unchanged. The various minor landlorms represented mythological animals, people, and events of the Dreamtime. Later investigators interpreted the residual as remaining after long-distance scarp retreat, or as due to scouring by the wind or by the waters of a huge lake. The inselberg and its decorations have been construed in terms of climatic variations. Uluru also has been interpreted as a compressed and resistant compartment that was exposed as a low rise in the latest Mesozoic. The initial rise shed runoff. The steep flanks were shaped in the Eocene by deep subsurface weathering followed by stripping of the regolith and exposure of bedrock forms. Large tafoni and breaks of slope were formed on the southern side where permeable sediments abutted the residual. Following their exposure, basal flares and footcaves were shaped during a later period of subsurface weathering. The inselberg has grown as a relief feature not by uplift, but by the lowering of the surrounding plains. The morphology of Uluru is an expression of episodic exposure. [ABSTRACT FROM AUTHOR]

Abstract: Patterns of plant diversity were examined across 24 ironstone ranges in arid south western Australia. The high levels of beta diversity displayed between ranges primarily resulted from high turnover of perennial species and was not influenced by the lower species richness on the more arid ranges. The variance in composition of the vegetation across the ranges was evenly distributed between the broad spatial pattern and environmental factors measuring climate gradients, local site variables and soil chemistry. In contrast broad scale spatial and climatic gradients were most important in explaining the variance in perennial species richness. Ranges along the boundary of the Arid Zone appear to have acted as refugia during the climatic cycles of the Tertiary with several hotspots of species endemism and taxa with distributions centered on these ranges. On the more arid ranges these specialist ironstone taxa are largely absent. The variation in richness of these specialists taxa was strongly influenced by patterns in soil chemistry in addition to the broad scale spatial and climate gradients. The concentration of the ironstone specialist taxa is largely coincidental with the most prospective areas for iron ore mining and this will provide considerable challenges in conserving these unique ecosystems. [Copyright &y& Elsevier]

Mount Augustus (Burringurrah) at 1105 m AHD, is a prominent elongate inselberg, underlain dominantly by resistant sandstone of Middle Proterozoic age (1.6 billion years old). It is located midway between Meekatharra and Carnarvon in semi-arid Western Australia. The Mount Augustus Sandstone and overlying sediments were folded and tilted about 1 billion years ago, providing the template for the modern Mount Augustus. It is essentially a structural landform. Its shape broadly conforms to the underlying asymmetrical anticline, which has a steep northern limb and a gentler dipping southern limb. The anticline plunges at a shallow angle to the southeast. The mountain is the core of the original fold and it stands some 700 m above the surrounding Gascoyne planation surface. Other rock types present on Mount Augustus include metamorphic and igneous rocks, which preclude it from being termed a monolith. Weathering, fluvial erosion and sedimentation have modified the original bedrock structures. Fluted bedrock provides evidence of rapid runoff from bare bedrock surfaces. A joint system has influenced the orientation of a step-like sequence of numerous scarplets on slopes. The weathered rock is red, but the coloured rock is only a centimetre deep on most surfaces. The surrounding alluvial, gibber and sand plains shallowly bury the eroded bedrock plains of the Gascoyne planation surface. Former alluvial fills have been ferricreted in the lower reaches of some channels and are currently being eroded. Mount Augustus has often been compared with Ayers Rock, and unwarranted claims have been made that it is the biggest rock in the world and the world's biggest monolith. [ABSTRACT FROM AUTHOR]

Abstract Aim To investigate if the current theories associated with recruitment strategies are sufficient to explain differences in the proportions of obligate seeders and resprouters on inselbergs and in the matrix. Location The New England Batholith of eastern Australia. Methods The importance of life form and regenerative response of flora species are compared for twenty-four archipelagos of inselbergs habitat islands and for their adjacent matrix. Forward stepwise multiple linear regression is used to correlate measured and modelled variables with differences in the proportional abundance of obligate seeders on inselbergs at three levels of sampling. Results A total of 216 inselbergs were surveyed and information on 826 vascular plant species was collated. Herbs were the most common life form both on and off inselbergs. There were generally more shrubs on inselbergs than in the matrix. Resprouters were more common everywhere. However, obligate seeders were proportionately more common on inselbergs. The degree of insularity of outcrop floras accounted for 23–37% of the variance in the proportional abundance of obligate seeders at three sampling scales. Main conclusions A model is proposed whereby the mechanisms that influence the abundances of obligate seeders and resprouters are different on inselbergs and in the matrix. Inselberg environments are harsh, arid, have limited safe recruitment sites and below ground resources, but are not light limited. In such habitats, obligate seeders with persistence life-history traits are favoured. Within the matrix in eastern Australia frequent biomass removal disturbances occur (such as fire) and resprouting is advantageous. High turnover obligate seeders with no persistence life-history traits can be favoured in the matrix with a reduced disturbance regime and where competition for light still occurs. Some of these matrix obligate seeders occur on inselbergs due to their infrequent disturbance regimes. [ABSTRACT FROM AUTHOR]