A long-term study into jarrah forest (Eucalyptus marginata) establishment at restored mine sites has found that they are in fact resistant to climate variability.
In their latest paper, published in the Journal of Ecology, Assistant Professor Rachel Standish and Australian Laureate Fellow, Professor Richard Hobbs from The University of Western Australia's School of Plant Biology, Professor Raphael Didham from the School of Animal Biology and others sought to understand forest resilience, otherwise known as its ability to ‘bounce back' or recover from disturbance.
"Data availability on forest resilience to drought is limited," Assistant Professor Standish said. "In particular, data on seedling establishment is critical because it is the first phase of recovery."
The researchers were able to analyse the long-term records collected by Alcoa of Australia to monitor the success of jarrah forest restoration following bauxite mining. The records covered a 19-year period between 1992 to 2010 and included annual data on seedling establishment at restored mine sites for 587 species in 1,938 plots in south-western Australia.
South-western Australia provides a unique test-bed because it is one of the few places in the world that has already experienced significant climate change. The jarrah forest ecoregion has experienced warmer temperatures and a 17 per cent reduction in mean annual rainfall over the 36 years from 1975 to 2011 compared with the 74 years prior.
"We found that seedling establishment occurred as much in drought years as it did in wet years," Assistant Professor Standish said. "We think this is because of high reliability of rainfall despite declines in amounts of rainfall.
"Our next step is to test some of the factors that might be important for determining whether forests recover, such as whether there is a connection to undisturbed forest and the size of the forest patch affected by drought."
The paper: Long-term data suggest jarrah-forest establishment at restored mine sites is resistant to climate variability, published in the Journal of Ecology was funded by Alcoa of Australia Ltd and the Australian Research Council Centre of Excellence for Environmental Decisions.
Assistant Professor Rachel Standish (UWA School of Plant Biology) (+61 8) 6488 1073
Professor Raphael Didham (UWA School of Animal Biology) (+61 8) 6488 1468
David Stacey (UWA Media Manager) (+61 8) 6488 3229 / (+61 4) 32 637 716