I am a marine chemist by training, with research interests in the area of trace metal chemistry in marine systems. I am particularly drawn to questions at the interface between chemistry and biology in trace metal cycling, such as how biota influence the chemical speciation of trace metals in seawater.
Current Graduate Students
Kayleen is a first-year graduate student with a chemistry background and an enthusiasm for learning about marine chemistry. Her experience in chemistry will be useful for exploring oceanographic processes on the molecular scale. Details to come...
I am interested in researching the speciation of trace metals necessary for phytoplankton growth. Many of these metals like iron and copper are highly complexed by organic binding ligands. Understanding the extent to which these metals are bound by ligands will help in understanding how bio-available trace metals are for phytoplankton utilization. There is a growing knowledge about metal speciation but some metals, like iron, are more thoroughly studied than others like copper. There is also little knowledge about processes that form the ligands that bind to metals. I am looking to understand the current state of the speciation of trace metals like iron and copper as well as the processes that produce the ligands that bind these metals.
Iron is a necessary nutrient for organisms, yet its scarcity in the marine environment makes it difficult for marine organisms to obtain, and it has been shown to be a limiting nutrient in the primary productivity of some regions of the world’s oceans. As a result, many marine microorganisms have developed specialized mechanisms for the uptake and metabolism of iron, including the ability to produce and take up iron-binding ligands. I am broadly interested in studying these mechanisms in heterotrophic marine bacteria. As major facilitators in the turnover of organic matter in the oceans, marine bacteria play an important role in the cycling of many elements in the ocean and also have a significant iron requirement. I am particularly interested in understanding how iron limits the growth of heterotrophic marine bacteria, how their metabolism of iron contributes to the transformation and cycling of extracellular iron, and what impacts this may have on other biogeochemical processes such as the carbon cycle.
I am interested in understanding the biogeochemical cycling of bioactive trace metals in the modern ocean. The behavior of these ultra-low concentration metals limits primary growth in vast swaths of the ocean. Since 2012, I have used novel technologies to analyze seawater and marine particles for trace metals in climate sensitive Antarctic shelf systems and the Southern Ocean. Now, I continue to use analytical techniques to investigate the comparative roles of different sources as well as mechanisms that control bioactive trace metals in the water column, and therefore, control ocean productivity in a changing seascape.
Additional Lab Members
Dorothy Parker – Research Associate
Shane Hogle – Former graduate student, now a postdoctoral fellow at Massachusetts Institute of Technology.
Randie Bundy – Former graduate student, now a postdoctoral fellow at Woods Hole Oceanographic Institution.
Kelly Roe – Former graduate student, now an adjunct lecturer at Rochester Institute of Technology.
Christopher Dupont – Former graduate student, now an Assistant Professor at the J. Craig Venter Institute.
Brian Hopkinson – Former graduate student, now Assistant Professor at the University of Georgia.
Andrew King – Former graduate student, now a Research Scientist at the Norwegian Institute for Water Research, Bergen, Norway.
Kristen Buck – Former postdoc, now an Assistant Professor at the University of South Florida.
Julian Herszage – Former postdoc, now a lab manager in the Agroecology Lab at UC Davis, with Dr. Johan Six.