Laboratory Alumni

Kelsey Dowdy

Kelsey Dowdy (undergraduate student)


Now enrolled at graduate school at the University of California, Santa Barbara as a NSF graduate research fellow, Kelsey came to Siberia twice as part of the Polaris Project and worked with us on projects focused on the fate of permafrost thaw organic matter.
bio_grater

Lizzie Grater (undergraduate student)


Lizzie is now a graduate student at the University of Quebec at Trois-Rivieres. Her research continues to focus on organic matter characterization and carbon cycling, particularly related to land-use impacts.
Francois Guillemette

Dr. Francois Guillemette (Postdoctoral researcher)


Currently an Assistant Professor at the Université du Québec à Trois-Rivières his research interests revolve around the fields of aquatic carbon biogeochemistry and microbial ecology. Of particular interest is the export, transformation and fate of dissolved organic carbon from land to a vast array of aquatic ecosystems such as rivers, wetlands, and lakes, and the understanding of the metabolic response of microbial communities to changes in the supply, age, source and composition of the organic carbon pool. He uses a suite of molecular and optical tools such as high-resolution mass spectrometry, spectrofluorometry and size-exclusion chromatography, as well as stable and radioisotopes, and modeling. Aside from his research program, he also has great interests in public education for the preservation, valuation and restoration of aquatic ecosystems.
Maddie Larue

Maddie Larue (undergraduate student)


Initially interacted with us as an undergraduate on the Polaris Project in Siberia and then worked as a summer laboratory intern focused on extracellular enzyme activity in Arctic aquatic ecosystems. Maddie currently works for the Environment Protection Agency.
bio_luzius

Casey Luzius (Graduate student)


As an MSc student at Florida State University, my research focused on identifying and tracing natural and anthropogenic organic matter sources at Wakulla Springs – one of the largest and deepest freshwater springs on Earth. I used optical measurements (fluorescence and absorbance) and ultrahigh resolution mass spectrometry to characterize dissolved organic matter (DOM) throughout sinks and conduits in the Wakulla Springs Basin to delineate DOM sources to the spring outflow. These measurements tied together land use and origin of the DOM to assess drivers of water quality found at the major springhead.
bio_mann

Paul Mann (Postdoctoral researcher)


Currently a Research Fellow at the University of Northumbria (U.K.) Paul conducted research examining the mobilization, processing and fate of permafrost derived organic matter in Siberian fluvial networks. Paul used a wide range of techniques to conduct this research from enzyme assays to stable and radiocarbon isotopes.
bio_olmsted

Emily Olmsted (undergraduate student)


With a strong interest in water quality issues Emily worked with us as a summer intern focused on nutrient loading issues to freshwater and coastal environments. Her work with a local conservation agency was used to write her senior thesis linking land-use to water quality problems.

Dr. David Podgorski (Professional researcher)


Currently an Assistant Professor in the Department of Chemistry at the university of New Orleans David is an analytical chemist with a unique background in the development and implementation of methods in the field of organic matter characterization. His research focuses on applying a diverse array of analytical methods to answer fundamental, hypothesis-driven questions in the fields of biogeochemistry and petroleomics. Core to his research program is the development of analytical methods aimed at unlocking the compositional and structural continuum of organic matter, particularly dissolved organic matter (DOM).

Holly Smith (undergraduate student)


Holly spent three semesters working in the lab extracting samples from the Yukon Flats in Alaska to the Congo River Basin. She also helped to analyze lignin samples from lakes and rivers in interior Alaska to trace organic matter sources across the boreal and Arctic landscapes. As a recent graduate Holly plans to continue in the sciences incorporating research and outreach in her career goals.

Sadie Textor (Graduate student)


Based on my interest in the underlying mechanisms of carbon fluxes to the atmosphere, I conducted research on the carbon priming effect at the terrestrial-aquatic interface. Priming is a possible mechanism by which biolabile organic carbon inputs increase the bioavailability of the more stable DOM in riverine systems, thus making it more susceptible to mineralization. Beyond looking at its potential to stimulate biogenic carbon dioxide production from previously stable components of the DOM pool, I investigated if the microbial community selectively utilizes certain components based on preferences in quality. I conducted experiments focused in both blackwater swamp and Arctic permafrost systems using techniques such as bioincubations, dissolved organic carbon analysis, fluorescence spectroscopy, and FT-ICR MS to distinguish various constituents of the DOM pool.