I'm a 3rd-year PhD Candidate in Keryn Gedan's lab at George Washington University. I study how coastal forests respond to sea level rise.
Rising sea levels pose a pair of problems for coastal forests: groundwater salinity is persistently elevated, and seawater floods occur more frequently. Trees can mitigate ionic stress by trading off ionic safety for hydraulic and/or carbon risk. For example, excluding overly-salty water at the roots creates pseudo-drought conditions, and shutting down stomata inhibits carbon assimilation. I'm working on quantifying those tradeoffs through a combination of field studies and optimization models.
Previously, I was a technician in Nate McDowell's group at the PacificNorthwest National Laboratory, studying both tropical forests and temperate coastal forests. Before that, I worked on plant-microbe interactions in the phyllosphere during my time in Joy Bergelson's lab at UChicago as an undergrad.
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Seawater Inundation Induces Reverse Sap Flux In A Coastal Forest
Sea level rise subjects coastal forests to persistently elevated groundwater salinity and increased inundation frequency. Some forests die, forming "ghost forests", while others persist. The mechanisms that determine outcomes for trees under a changing climate remain unresolved. We investigated how loblolly pines respond to a saltwater flooding event across a forest dieback gradient. Prior to the flooding event, trees in the most saline plots had sap flux (SF) rates that were approximately 75% lower than trees in less saline plots. When a high-tide saltwater flood event occurred at our site in May 2021, water levels rose by over half a meter and groundwater salinity rose by 18 ppt, remaining elevated for weeks. At the flood event's onset, loblolly pine trees across the site exhibited reverse SF. While reverse SF has been observed previously in cases of hydraulic redistribution across heterogeneously dry root zones, to our knowledge, this is the first empirical evidence that ionic gradients alone are sufficient to induce reverse SF in saturated conditions. We found that despite steep water potential gradients in the root zone, SF rates in the week following the inundation event are consistent with predictions from a stomatal optimization model validated against pre-event data.