Gums could succumb to shifting climate
Ecologists say up to 90 per cent of eucalypt species face declines in the face of climate change.
Suitable environments for the country’s iconic eucalypt trees could decline within a generation, according to international research led by the University of Canberra.
Associate Professor Bernd Gruber from the university’s Institute for Applied Ecology (IAE) says 16 species are forecast to lose their home environments entirely within 60 years, due to climate change.
The study examined the impact of climate change on the distribution of a large group of closely related tree species on a continental scale.
“This study demonstrates the importance of not simply counting the number of species in biodiversity conservation, but also considering their evolutionary history, which determines how closely related species are to each other,” Dr Gruber said.
“Using this approach we were able to identify hotspots that will contain high levels of eucalypt diversity under a changing climate, both in terms of the number of species and their reflection of the trees’ evolutionary pathways.
“Protecting these hotspots will be important to ensure we retain biodiversity in the future.
“We predict that a three degree rise in temperature over the next 60 years would see a decline of suitable habitat for 91 per cent of the 657 species of eucalypts we studied.
“As a consequence, the distribution of many species will change, and we expect trees suited to temperate and southern Australia to be hit particularly hard, contracting to more climatically suitable areas further south or at higher elevations.
“At least 16 species would have suitable climatic zones disappear altogether,” he said.
The study was made possible by the close collaboration of researchers including experts in France who obtained DNA from the leaves of over 700 eucalypt species, many of which were cultivated in Australian Botanic Gardens.
Additionally, supercomputers were used to model the climatic distribution of all 657 species on a continental scale at a very high level of detail. The models were based on over 260,000 geospatial data points of eucalypt specimens stored in Australia herbaria and accessed through Australia’s Virtual Herbarium.