IN020-07
Impacts of cascading environmental hazards on Australian plant biodiversity
Thursday, 10 December 2020: 16:24
Virtual
Cory Merow1, Rachael V. Gallagher2, Stuart Allen3, Emmanouil N Anagnostou4, Kang He5, Brian S. Maitner6, Efthymios I Nikolopoulos7, Xinyi Shen4, Vanessa Adams8, Samuel Andrew9 and Brian Joseph Enquist10, (1)University of Connecticut, Department of Ecology and Evolutionary Biology, Storrs, CT, United States, (2)Macquarie University, Department of Biological Sciences, North Ryde,, Australia, (3)Macquerie University, Sydney, Australia, (4)University of Connecticut, Civil and Environmental Engineering, Storrs, CT, United States, (5)Zhejiang University, Institute of Agricultural Remote Sensing and Inofrmation Technology Application, Hangzhou, China, (6)University of Arizona, Tucson, United States, (7)Florida Institute of Technology, Mechanical and Civil Engineering, Melbourne, United States, (8)University of Tasmania, Tasmania, Australia, (9)CSIRO, ACT, Australia, (10)University of Arizona, Ecology and Evolutionary Biology, Tucson, AZ, United States
Abstract:
The 2019/20 fire season in Australia ravaged the continent at levels not seen in recorded history. Unprecedented droughts, record high temperatures, and an abundance of dry biomass colluded to produce extensive and severe burns. Immediately following these fires, in some regions, came torrential downpours that caused localized flooding and erosion. This cascade of hazards has dramatic impacts on existing plants species’ distributions, their ability to sustain viable populations, and the feedbacks to ecosystem recovery. We developed a rapid response initiative as a collaboration between ecologists, environmental engineers, data scientists and conservation biologists to (1) quantify the extent of burnt area across species ranges; and (2) assess the risk of these cascading environmental hazards in the coming century. We developed continent-wide high-resolution layer describing these hazards, include drought metrics, fire severity, biomass recovery following fire, and flooding. We then generated the first comprehensive set of distribution maps for all plant species in Australia with data. These were combined to assess the impacts on 19,000+ Australian plant species to determine how the 2019/20 hazards compare to historical trends in driving biodiversity loss. By quantifying the risk status for all Australian plant species based on their exposure to different combinations of hazards, we prioritized species for monitoring and management.
We found that the 2019 drought was the worst in the precipitation record (since 1980) and the extent of fires in New South Wales was the worst in historic record (since 2003). 1,335 species assessed were listed under federal protection (FP), and 4,622 were listed under state-based protection. 8% of FP taxa had more than 50% of their range burned during the 2019-2020 fire season. In New South Wales, the region hardest hit by fires, regional endemics were heavily impacted and high-risk species included 132 affected by the interaction of drought and fire, 77 affected by short fire intervals, 158 affected by high fire severity, and 114 affected by post fire erosion. Future droughts are expected to increase in frequency across much of the continent, implying that the 2019/20 fires may be representative of the future conditions in Australia.
