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Salinity
Increasing salinity is one of the most crucial environmental problems facing Australia. While salt is
naturally present in many of our landscapes, European farming practices which replaced native vegetation
with shallow-rooted crops and pastures have caused a marked increase in the expression of salinity in our
land and water resources. As a consequence groundwater levels rise, bringing with them dissolved salts,
which had previously been stored within the ground for millennia. In this way, salt is being transported to
the root-zones of remnant vegetation, crops, pastures, and directly into our wetlands, streams and river
systems. The rising water tables are also affecting our rural infrastructure including buildings, roads,
pipes and underground cables. Salinity and rising water tables incur significant and costly impacts.
The impacts of salinity are separated both in time and space from its causes. This means that while
Australia's salinity problem is already significant, it is expected to increase as a result of past and present
practices. For example, the National Land and Water Resources Audit estimates that 5.7 million hectares
have a high potential for the development of dryland salinity, and predicts this to rise to 17 million
hectares by 2050. This creates a major challenge for governments, industry and the community to develop
management approaches which protect environmental and human assets which are at risk; address the
problem of rising water tables; and make productive use of saline resources.
Environment Australia, together with the Agriculture, Fisheries and Forestry -Australia, is providing
national leadership in salinity and water quality management through the National Action Plan for Salinity
and Water Quality, which was endorsed by the Council of Australian Governments on 3 November 2000.
The National Action Plan seeks to prevent, stabilise and reverse trends in dryland salinity and to improve
water quality and secure allocations for a range of uses.
The above is an artical from the Environment Australia web site. I reccomend this site and I am happy to include a link
http://www.ea.gov.au
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EUCALYPTS UNDER THREAT
'Australias eucalypts are under greater threat today than ever before,' said Wilson Tuckey, Minister for
Forestry and Conservation at the launch of the book Diseases and Pathogens of Eucalypts at Parliament
House, Canberra.
The current state of knowledge of eucalypt pathogens and diseases has been assembled in the book that
was edited by Prof Phil Keane, Dr Glen Kile, Dr Frank Podger and Dr Bruce Brown.
Minister Tuckey said, 'The global importance of eucalypts for wood production, land rehabilitation and
local amenity plantings is not always recognised by Australians.
Most of us don't realise that eucalypts are the most widely planted hardwood trees in the world.
'As well as helping to meet the growing world demand for cellulose fibre, timber and firewood, they are
being used to renew the seriously depleted timber and firewood resources associated with poverty in
many countries.
'A good knowledge of the diseases and pathogens that hinders their growth is, therefore, very important.
This book brings that together and makes it available to all interested parties.'
Destructive disease epidemics, particularly dieback caused by the cinnamon fungus over vast tracts of
native forest in south-eastern and south-western Australia, and foliar diseases of plantations in Australia,
New Zealand and South Africa, have
stimulated intensive research into the cause and management of diseases of the eucalypts.
When eucalypts were first grown outside Australia, in the absence of their co-evolved parasites, they
appeared healthier and more vigorous than in their native land. Later, as the plantings became more
extensive, the trees began to suffer attack by pathogens, sometimes introduced from Australia and more
recently from local plants moving onto the introduced eucalypts.
Eucalypt diseases have the potential to reduce the productivity of the newly emerging plantation industry
in Australia. Mr Tuckey said, 'We do need to be careful that those pathogens, which have recently moved
onto eucalypts in other countries, are not accidentally imported into Australia.'
New introductions could have a serious impact on conservation value of native forests as well as
commercial values of plantations. This is the first, globally comprehensive compilation of material related
to eucalypt diseases and pathogens. It includes contributions from 31 experts from Australia and
elsewhere in the world.
It includes an account of the general biology and genetic diversity of the eucalypts as
a basis for the diagnosis and management of disease, taxonomic information on pathogens and diseases
they cause, and the options and constraints for managing disease in native forests. Further inquiries:
Mr Tuckey's office: Graeme Hallett 0419 688 440
La Trobe University: Professor Phil Keane (03) 9479 2219
CSIRO Forestry
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