Summary
- Major: Environmental Science
- Faculty Mentor: Dr. May Gustin and Dr. Heather Haines
- Research Topic: The effect of drought on records of atmospheric mercury: Analyzing tree rings through industrialization to present day
- New Scholar: 2022 Cohort
- Graduating with a Baccalaureate Degree: 2024
Abstract
Human activities related to industrialization have increased atmospheric pollutants. One such pollutant is mercury (Hg), which has proven to have severe detrimental impacts on natural ecosystems. The exact amount by which atmospheric mercury concentrations have increased over time are poorly understood; therefore, this project aims to develop a high-resolution record of atmospheric mercury using tree rings since 1850. Here tree rings from Giant Sequoia trees located along the USA western coast serve as an annual archive of atmospheric mercury. Trees take up mercury from the air via the stomata, and mercury is transported to tree rings via the phloem, generating an annual record of atmospheric mercury concentrations through time. In addition, during drought stomata on the needles close and change the ratio of Carbon-13: Carbon-12 isotopes. By analyzing the carbon isotope ratios and mercury in annual sequoia tree rings, we can understand how drought has influenced tree atmospheric Hg uptake. These results will inform our understanding of how drought events affect mercury uptake within tree rings, and by extension the impact of climate on the historical record of mercury found in the rings. Additionally, these results will provide insight on how both natural and anthropogenic activities affect mercury in the environment allowing for better management of potential causes of damage to natural ecosystems.