Speaker: Dr. Kasey Barton
Climate change is altering water availability with dramatic consequences for plant performance and population stability. Seedlings are often more sensitive to water limitation than older plants of the same species due to their small size, relatively limited stored reserves, and acquisitive growth strategy. Because climate change is not only reducing total incoming precipitation, but also the timing, seedling recruitment is declining in many Hawaiian plants. Using experimental approaches in the field and greenhouse, combined with ecophysiological trait analysis, we have been investigating seedling drought tolerance across a diverse range of native and invasive Hawaiian plant species. Key findings include detection of climate mismatches constraining seedling germination and establishment in Hawaiʻi’s foundation tree, ʻōhiʻa lehua (Metrosideros polymorpha), confirmation that seedlings are sensitive to the timing as well as amount of water availability, significant variability across species in their potential tolerance to and longevity under extreme drought, and identification of interactive effects with herbivory. These studies indicate widespread and complex vulnerability of Hawaiʻi’s native plants to drought, highlighting seedling recruitment as a critically threatened process potentially leading to population instability and declines.
November 18, 2022 recording (click here)
May 6, 2022 Transcript (download here)
May 6, 2022 Recording (click here)