Australian tree species threatened by rising CO2

The iconic Australian river red gum tree is under threat from rising carbon dioxide (CO2) levels in the atmosphere, researchers from the Australian National University (ANU) said on Friday.

River red gums are Australia's most widespread eucalyptus tree, found on river banks throughout the country. A study by Carsten Kulheim from the ANU's Research School of Biology has shown that rising levels of CO2 threatens the future of the species.

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, reports Xinhua news agency.

"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 (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.

--IANS

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