Australia: The Land Where Time Began

A biography of the Australian continent 

Arid Australia - a Fresh Framework for its Ecology

In this paper the authors¹ present a revised set of proposals that are based on research literature since the publication of Smith & Morton (1990). The authors¹ say their argument has distilled 14 proposals that most features of deserts in Australia are explicable in terms of 2 dominant physical and climatic elements - rainfall leading to extended droughts and occasional rain that leads to flooding, and nutrient poverty that is widespread across the arid areas of Australia. These features are shown in varying degrees by different landscapes in the arid zone, making it important to think about the different places separately when the propositions of the authors¹ are being considered. As the rain received by Australian deserts is more variable than most others there is a distinctive spectrum of life histories, with plants life histories strongly reflecting temporal patterns soil moisture.  Plants that produce relatively excess levels of carbohydrate (C) are favoured by soils that contain low levels of phosphorus and receive abundant moisture at irregular intervals. This sometimes leads to ecosystems that are prone to fires, assemblages dominated by consumers of sap and other C-based products, and abundant detritivores, especially termites. The variability of the rainfall leads to fluctuations of production and this leads to consumers with life histories that are opportunistic, and this includes inhabitants of extensive, ephemeral lakes and rivers. Some flexibility of diet or a diet that utilises more dependable resources are exhibited by most consumer species, these strategies beading to a high level of stability in species dynamics and assemblage composition than might be expected under such a regime of variable rainfall. There has been A long-standing ecological influence by Aboriginal people as they gathered food. The sauthors¹ say that for each of the propositions they have suggested the extent of its "difference", "accentuation" or "universal" compared with deserts around the world, recognising the need for critical testing of this categorisation. For each proposal further tests are also suggested to fill the many existing gaps in the current knowledge of structure and functioning of deserts in Australia.

Sources & Further reading 

1. Morton, S. R., D. M. Stafford Smith, C. R. Dickman, D. L. Dunkerley, M. H. Friedel, R. R. J. McAllister, J. R. W. Reid, et a