Feature: what Australian eucalyptus tree can tell us about climatic past and future-Xinhua

Feature: what Australian eucalyptus tree can tell us about climatic past and future

Source: Xinhua

Editor: huaxia

2022-08-19 14:42:45

SYDNEY, Aug. 19 (Xinhua) -- As part of National Science Week, a panel of experts held a discussion on Australia's most important and dominant tree, the eucalyptus, which is both at risk and a potential solution in the face of climate change.

The discussion, titled "The Eucalyptus: Sentinels of a Changing Climate", took place on Thursday night in the Powerhouse Museum as part of the Sydney Science Festival.

The eucalyptus is a family of over 800 species of native trees. They dominate over 75 percent of Australia's bushland, testament to their adaptation over millions of years to Australia's arid and fire-prone climate.

Belinda Medlyn, a professor at the University of Western Sydney who works on modeling how the trees will be impacted by climate change, said this seeming high-degree of resilience is masked by each species' adaptations.

"They're all over the country, but most of them have their own little niche. They have a small area that they need, which would tend to suggest that they are quite vulnerable to climate because they're really quite specialized."

In 2018 Medlyn started the Dead Tree Project, which seeks to view trends of how and the rates at which Australian trees are dying.

The ongoing research has found that while droughts and fires are a natural part of Australia's ecosystem, their frequency and intensity could see entire species of the tree wiped out or even prompt ecological collapses.

One study from the University of Canberra found that in a worst case scenario, a three degree rise in temperature would see a 50 percent reduction of 90 percent of eucalyptus species.

Beyond the trees' ability to sequester large amounts of carbon dioxide, they are also the basis on which Australian ecosystems thrive.

Rebecca Jordan, CSIRO Research Scientist, brought her focus on genetics to the discussion, and how it might help conservationists ensure the trees survival.

"I like to think of genetic diversity like a tool kit, the more tools we have in that tool kit, the more options that an organism might have to deal with whatever challenges are coming into the future with these changing climates."

For instance, she said eucalyptus trees growing in Australia's southern states have specific adaptations to wetter cooler conditions, and those in the north hotter and drier conditions. She said by breeding these species scientists could create trees that have both genetic defenses.

Indigenous expert and filmmaker, Victor Steffensen's view of the eucalyptus tree stood in contrast to the other two speakers.

In many ways the panel highlighted the disconnect and tension between Aboriginal Australians' spiritual connection to the environment, and the data and science-driven Western approach to conservation.

"Their (tree's) identity is in their soil, the gifts they give to us, where they live, and the community that they bring. Trees aren't on their own, they bring the whole community," he said.

Speaking to Xinhua after the seminar, Steffensen acknowledged the struggle of combining traditional knowledge with modern science, which spoke the language of policy makers.

"Western policies and Western land management is totally opposite to Aboriginal land management and thousands of years of understanding this landscape," said Steffensen.

He added that it was important not only to integrate traditional knowledge into modern research, but also to get behind indigenous practices.

All three panelists agreed that collaboration would be key to preparing Australia and its trees for climate change, but the challenge of integrating vastly different practices remained in the air.

Australia's National Science Week runs every year in August, and features thousands of science events hosted across the country.