The Footprint 2011 Summer Edition - Eyre Peninsula Natural ...

Caring for our natural resources
Redgums recovering well
Redgum trees growing in the Polda
Basin have responded well to the past
two years of good rainfall and recharge
to the groundwater basin.
That’s the assessment of applied ecologist
Dr Kerri Muller, who has been contracted
to determine the water requirements of
redgum trees in the Polda Basin area on
the West Coast for Eyre Peninsula Natural
Resources Management Board.
“Although the gums at Polda show signs
of past water stress, they are currently
growing new leaves and in many cases,
flowers, Many gum trees in SA have
suffered during the recent dry years and
the response to better conditions that we
are seeing in the redgums at Polda appear
to be responding as strongly as has been
observed in redgums anywhere in the
State” she said. “By observing them over
time we will further our understanding of
their responses to changes in groundwater
levels and quality.”
The initiative was prompted by concerns
expressed about the redgums by local
residents who are members of the
Musgrave Water Allocation Consultative
Committee. This committee, and a similar
committee for the Southern Basins, was set
up by the Board as part of its community
consultation during the development of
the new draft Water Allocation Plan for the
Musgrave and Southern Basins Prescribed
Wells Areas.
The Southern Basins covers the Lincoln,
Coffin Bay and Uley underground basins,
while Musgrave covers the basins to
the east of Elliston, including the Polda,
Kappawanta, Sheringa and Bramfield
lenses.
EPNRM water resources program manager
Terry Boyce said the Board would carry
out the proposed monitoring regime when
it was finalised.
Dr Muller is a member of a team working
with the Department for Water which will
provide the Board with a series of scientific
reports that will underpin the development
of the draft WAP. EPNRM will continue to
work with the Consultative Committees to
further develop the draft WAP in 2012.
The proposed monitoring regime will be
Elliston-based EPNRM officer Rob Coventry and Russell Dudley, a
member of the Musgrave Water Allocations Consultative Committee
developed based on a report being written by Dr Muller and
another ecologist, Tim Doeg, on the environmental water
requirements of a number of native vegetation species that
depend on groundwater on EP.
Mr Boyce said the Board had followed up on a number of other
issues raised by the committees, including rainfall variability,
projected water demand for stock and domestic use and the
potential impacts of climate change on water supply.
Dr Muller made an initial assessment of redgum health in
the Polda Basin in July and again in November following her
presentation to the Musgrave committee in Elliston.
Dr Muller said the issues of grazing of seedlings and wood
cutting also needed to be addressed to ensure the long term
health of the redgum stands. She said that like many Australian
plant species, redgums had evolved a number of adaptations
to help them survive droughts and it was a mistake to assume
they were dead or dying if they dropped their leaves.
“Redgums often drop their leaves when water stressed and
it can be quite difficult to work out which trees will come back
after a good season and which ones will not,” she said. “They
can have many lives.”
“It is really important that trees are properly assessed before
being cut down for wood or furniture. Even then we should
take as few as possible because dead trees provide a lot of
functions in the ecosystem, such as nesting sites, shelter,
organic matter, carbon stores and erosion control.
Other species that will be covered in the report include
Melaleucas, samphires, Gahnia grasses, sedges, rushes and
underwater plants.
For more on the development of the new WAP, go to http://
www.epnrm.sa.gov.au/WaterResources/WaterAllocation-
Plans/NewWaterAllocationPlan.aspx
EPNRM footprint summer edition 2011 7