PhD Candidate The Australian National University, Australian Capital Territory, Australia
Abstract: In a future where we expect climate conditions to change and become more variable, plants broadly will be exposed to increased heat and cold stress. This could result in a change in the distribution of suitable habitat for many plants, with species forced out of currently occupied areas due to extreme local climate conditions beyond the thermal niche breadth of the plant populations. Inferring niche changes under future climates is usually based on correlative species distribution models combined with climate projections. However, approaches that incorporate the functional thermal limits of species into these models to better manage niche-distribution mismatches, allowing for more accurate modelling. I compared the leaf thermal tolerance limits of Australian plants against the current species distributions modelled from occurrence records. Here, I report preliminary results of range size correlations of 69 Australian plant species based on physiological thermal tolerance data from field studies in multiple sites in alpine, temperate, and desert biomes across New South Wales, Australia. Preliminary results suggest a pattern of greater range size associated with broader thermal tolerance limits. I aim to investigate the role of changing temperature extremes at the upper and lower end of thermal tolerance ranges in determining future distribution changes. I then aim to highlight species that are under risk of extinction from possible range contraction under future climate scenarios.
