CANBERRA, June 23 (Xinhua) -- The iconic Australian river red gum tree is under threat from rising levels of carbon dioxide (CO2) in the atmosphere, researchers from the Australian National University (ANU) have said on Friday.
River red gums are Australia's most widespread eucalypt tree, found on river banks throughout inland Australia, but a study undertaken by Dr Carsten Kulheim from the ANU's Research School of Biology has shown that rising levels of CO2 threatened the future of the famous "Aussie" species.
In a statement released on Friday, Kulheim said that rising levels of carbon dioxide would have an adverse effect on the trees' production of "defence chemicals", putting them at risk of being stripped by harmful insects which are currently repelled by the chemicals.
"The future of the iconic river red gum is unclear even without taking the further effects of climate change into account," Kulheim said, "River red gums grow across all of mainland Australia and they are the most widespread gum tree we have.
"Since (the CO2 level) affects how the trees are able to defend themselves against leaf-eating animals, we wanted to find out how future increases in CO2 would affect river red gums defence chemicals."
Kulheim said the study uncovered a dark future for the river red gum should CO2 levels continue to increase, hinting that the defence chemicals could change, leaving them vulnerable to being destroyed.
"Some eucalyptus oils defend the gum tree from certain insects, others from koalas feeding on them," he said.
"This is just one of many examples of how greenhouse gas emissions affect our environment, providing further evidence that action is needed now."
