Bleak future for Australia's alpine flora

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Native plants in Australia's alpine regions may not be adapting quickly enough to survive rapid climate change.

"Australian native alpine plants face a bleak future in the face of rapid climate change," the University of NSW study's lead author Meena Sritharan concluded.

The study of 21 plants from Kosciuszko National Park found 20 weren't responding to warming conditions.

Just one species - the Star Plantain (Plantago muelleri) - adapted to warmer conditions by increasing in size.

A second plant that showed evidence of a change was the Cascade Everlasting (Ozothamnus secundiflorus), but it had decreased in leaf thickness over 125 years.

"We predicted leaves would become thicker, as this would be advantageous if plants were facing longer growing seasons and increasing temperatures," Ms Sritharan said.

"Our findings suggest that native alpine plants may not be adapting to the substantial local climate change occurring in Australian alpine regions."

The point of the study was to gauge whether alpine plants in the southern hemisphere had changed their physical form over time in response to climate warming.

Alpine environments are facing higher-than-average increases in temperature in the last century.

"But rapid changes in the environment can promote rapid changes in species."

The researchers used preserved plant specimens collected between 1890 and 2016, and modern specimens collected in 2017.

The results were contrary to what had been expected, as plants in the northern hemisphere were changing substantially and adapting to changed environmental conditions brought on by climate change.

Scientists also forecast that plant species would migrate to higher elevations to escape the effects of climate warming.

But they were surprised to find that a shrub - Cascade Everlasting (Ozothamnus secundiflorus) - had moved downslope over time rather than to a higher elevation.

Ms Sritharan is a PhD research scholar at ANU who participated in the UNSW study as an honours student.

The study is published in Ecology and Evolution.