Regional profile
The Arnhem region is one of the least disturbed areas in
Australia, and also includes a major portion of the Northern
Territory's coastline. It is unique in being virtually all under
Aboriginal ownership. However, since European settlement much of
the country has been depopulated, with consequent changes in fire
regimes. Roads, mines, townships and communities have disturbed
small areas of the landscape. Other areas have also been modified
by use as cattle stations.
Weed threats
Within the Arnhem region, little is known about the weed status
of most areas outside the major settlements. However, it does
appear that the region is currently one of the least weedy in the
world. Generally weeds are concentrated in disturbed areas around
townships, communities and outstations, although weed populations
are also increasing in areas such as the Arafura wetlands in
north-east Arnhem Land. Weed populations in much of the Arnhem
region are likely to increase rapidly without effective involvement
of local communities in weed management programs.
Mimosa spread
A notable example of how weed problems can quickly develop in
such a region was the severe mimosa infestation that developed on
the Oenpelli floodplain in the 1980s. Some control was undertaken
late in 1980s, but a concerted effort was not made until the 1990s
when 8000 hectares of floodplain were infested. An $8 million,
Commonwealth-funded program has reduced the extent of the
infestation, but it remains a major problem. Given the many
isolated occurrences of mimosa in the region, the potential remains
for further spread unless there is sustained effort in controlling
existing populations and rapid identification and eradication of
satellite outbreaks.
These issues are discussed in Smith, N. (2001). Unwanted
Exotic Plants on Northern Land Council Lands, Northern
Territory, Australia. Tropical Savannas CRC, Darwin. Click
on the link below to find out more.
