OOS 75

The Effects of Drought on the Formation, Resilience, and Recovery of Xylem Embolism in Plants: Linking Experimental Results and Synthesizing Observations

Emerging advances in ecological research have progressed our understanding of the complex process through which woody plants succumb to drought and temperature stress. Recent and ongoing experiments have begun to illuminate the interactions among water relations, carbon status and biotic agent damage with a goal of improving predictions of which species and regions are likely to experience woody plant death and dieback in future climates. Despite this progress, however, major uncertainties remain both in how trees succumb to drought and in understanding cross-species and cross-biome differences. This session seeks to capture the forefront of this exciting research area by integrating cutting-edge physiological research on single species and specific ecosystems with cross-system comparisons and syntheses. Drought induced embolism and the subsequent recovery is a new and rapidly expanding area of research. Although the mechanisms of refilling embolism under positive pressure, and via new growth over seasons, is well understood, the mechanisms involved in embolism refilling in different tissues, species and biomes remain unresolved. Other aspects of embolism refilling, such as the timeframes under which different types of embolism refilling can occur, are also hotly debated, with causative mechanisms needing further elucidation. Further, species differ in their resilience to high levels of embolism, and different species likely exhibit different embolism thresholds. This session provides a mix of novel research and syntheses on a highly debated and currently unresolved field of research. We have six confirmed speakers focusing on different ecosystems, so we can introduce a robust and diverse understanding of embolism recovery and mortality avoidance based upon water relations, life history traits, and microclimatic conditions across several plant functional types. Additionally, speakers working in regions including Europe, California chapparal, the tropics, southwestern U.S. coniferous forests and the southern hemisphere will provide insights into research across a broad range of ecosystems. We have confirmations from a mix of energetic ‘rising star’ early career scientists, and established professors providing overviews of recent embolism research.