Lindsay Li ’23


Undeclared
Reconstructing the History of Nutrient Conditions in the Mediterranean Sea at Times in the Past
Certificate(s): Environmental Studies
I investigated the context of the formation of sapropels — ocean sediment layers rich in organic material — in the Mediterranean Sea by working with foraminifera. One of the leading hypotheses for sapropel formation posits that escalated river runoff increased the availability of phosphorus, which spurred nitrogen fixation and thus productivity. The goal of my project was to identify and separate different foraminifera species into samples prepared for nitrogen-isotope analysis, the results of which can shed light on the potential of the river runoff hypothesis to predict an isotope ratio consistent with higher nitrogen fixation rates. I gained skills in identifying foraminifera and in microscopy, and learned much about the cycles, biogeochemical and otherwise, that govern the Mediterranean ecosystem. I thought the influence of astronomical cycles on ocean circulation was particularly interesting. I gained insight into lab work and research through this internship, and I’ve been inspired to continue to explore earth and environmental sciences.
2020
Climate and Environmental Science
Sigman Research Group, Department of Geosciences, Princeton University
Daniel Sigman, Dusenbury Professor of Geological and Geophysical Sciences, Professor of Geosciences; Ellen Ai, Ph.D. candidate, Geosciences