Travel Reference
In-Depth Information
The Outback Environment
Parts of the Australian outback are among the world's oldest land surfaces.
Australia's last great mountain-building events took place more than 300
million years ago, and it's hard to believe that Uluru was once part of a
mountain range that would have rivalled the Andes in height. Erosion and
the relentless cycle of drought and flood have leached the nutrients away
from Australia's ancient soils and prevented the creation of new soils, res-
ulting in the vast sandy plains of the Australian outback.
The Land
The Stuart Hwy passes through some of the lowest, flattest and driest parts of Australia,
but there are numerous ranges and individual mountains scattered through the outback. At
1531m, Mt Zeil is not remarkable by world standards, but it is the highest mountain west
of the Great Dividing Range. The rocky ranges of the outback provide important refuges
for a diverse collection of plants and animals, and are significant in the ancient song lines
and
stories
(accounts of the Dreaming that link into the law) of the traditional Aboriginal
custodians of these areas.
In the outback you will drive past huge salt or clay pans that rarely fill with water.
These may be dry for years, but when there is an abundance of rain they become import-
ant arid wetland systems: they hold water long after the surrounding landscape has dried
out and are crucial to the survival of many plants and animals, especially those that re-
quire inundation during their life cycles.
While spectacular geological formations are characteristics of the south and central
deserts, it is the extensive river systems and wetlands that herald your arrival in the Top
End. The sandstone escarpment and plateau of western Arnhem Land is a magnificent
sight, but the life- sustaining floodplains at its base are just as impressive.
SA's low and unreliable rainfall has resulted in water from the Murray River being piped
over long distances to ensure the survival of many communities, including Adelaide. More
than 50% of South Australians depend entirely on the Murray for their water supply, and
this figure can rise to 90% in drought years.
