Lead author, Dr Dana Bergstrom from the Australian Antarctic Division, said that the project emerged from a conference inspired by her ecological research in polar environments.
“I was seeing unbelievably rapid, widespread dieback in the alpine tundra of World Heritage-listed Macquarie Island and started wondering if this was happening elsewhere,” Dr Bergstrom said.
“With my colleagues from the Australian Antarctic Division and the University of Queensland we organised a national conference and workshop on ‘Ecological Surprises and Rapid Collapse of Ecosystems in a Changing World’, with support from the Australian Academy of Sciences.”
The resulting paper and extensive case studies examine the current state and recent trajectories of 19 marine and terrestrial ecosystems across all Australian states, spanning 58° of latitude from coral reefs to Antarctica. Findings include:
Ecosystem collapse (defined as potentially irreversible change to ecosystem structure, composition and function) is occurring now in 19 case studies. This conclusion is supported by empirical evidence, rather than modelled predictions.
No ecosystems have collapsed across their entire range, but for all case studies there is evidence of local collapse.
The 19 ecosystems include the Great Barrier Reef, mangroves in the Gulf of Carpentaria, the Mediterranean forests and woodlands, the arid zone of central Australia, Shark Bay seagrass beds in Western Australia, Great Southern Reef kelp forests, Gondwanan conifer forests of Tasmania, Mountain Ash forest in Victoria, and moss beds of East Antarctica.
Drivers of ecosystem collapse are pressures from global climate change and regional human impacts, categorised as chronic ‘presses’ (eg. changes in temperature and precipitation, land clearing) or acute ‘pulses’ (eg. heatwaves, storms, fires and pollution after storms).