Nemergut Group

Laboratory for Microbial Evolution and Ecology
Lab Members

Caroline Tucker, Post-Doctoral Scholar (also advised by Brett Melbourne)

My research has ranged broadly from understanding the impacts of temporal variation on species coexistence and community assembly, the implications of prioritizing and protecting different types of diversity, and the importance of competitive interactions on plant phenology. At the University of Colorado, Boulder, I’ll be working on understanding the mechanisms driving assembly of soil microbial communities post-disturbance and the implications for ecosystem functioning. I use a variety of tools, including mathematical models, observational data and experimental microcosms. I'm interested in microbial communities as a tool for understanding community dynamics at a manageable scale. My webpage is here:

Joey Knelman, EBIO PhD student

Recent investigations of chronosequences exposed on deglaciation are beginning to examine the dynamics of microbial succession and its influence on biogeochemical processes. Employing molecular and biogeochemical assays, my research seeks to explore how limited vegetation in these sites may alter microbial community succession and function in mediating biogeochemical cycles. Current projects include examining vegetated vs. non-vegetated soils at the Mendenhall Glacier in Alaska to gain insights on vegetative influence on microbial community structure especially in terms of N-fixing bacteria. Levels of soil nitrogen fixation are also being assessed. Additional research interests broadly include rhizosphere microbiology, plant-microbe interactions, and the role and succession of mycorrhizal communities among chronosequence vegetation.

Emily Graham, ENVS PhD student

I am investigating the relationships between environmental conditions, nutrient and pollutant biogeochemical cycles, and the microorganisms that regulate these cycles. I employ techniques from microbial ecology, biogeochemistry, statistical modeling, and environmental economics. Currently, I am conducting two primary projects. First, I am investigating the interactions between DOM characteristics, extracellular enzyme activity, microbial community structure, and mercury pollution in wild rice patches in the Great Lakes region. My preliminary research has shown that reduced humic-like portions of the DOM pool inhibit mercury methylation, the process that generates bioavailable mercury, in unvegetated areas, while the same portions of the DOM pool facilitate mercury methylation in vegetated areas. Current research investigates these relationships in wild rice patches, an economically and culturally important resource for Native American communities in the Great Lakes region. Secondly, I am conducting a metaanalysis project to evaluate the relative utility of environmental parameters and microbial data in predicting rates of biogeochemical processes, such as biological carbon dioxide uptake. The project aims to improve ecosystem process models and to allow decisionmakers access to more accurate information than current predictions. We have been actively soliciting datasets for our metaanalysis and have established collaborations with over 35 authors from around the world. Our current collaborators reside in diverse locations and study disparate ecosystems, ranging from here in Colorado to Europe, Asia, and Australia, and we hope to decipher common themes in the importance of environmental and microbial data in explaining ecosystem processes across the globe.

Sarah Sattin, EBIO MA graduate

Sarah finished her MA degree in May 2008. Her thesis was on microbial community succession in the forelands of the Mendenhall Glacier in Juneau, AK. Her thesis has been accepted for publication. Sarah is currently a researcher at SomaLogic.

Robert Kysela, EBIO MA graduate

Bobby finished his MA degree in May 2009. His thesis was on microbial community composition and the decomposition of dissolved organic matter in Costa Rican tropical rainforest soil. He was a VISTA volunteer in Bellingham, WA following graduate school and is now a medical student in Colorado.

Nick Mosely, EBIO Honors graduate

Nick completed his honors degree in May 2009. His thesis was on the structure and function of lake biofilm microbial communities. He is currently a graduate student at the University of Washington.

Lee Stanish, ENVS PhD graduate (with Diane McKnight)

Lee's research focused on investigating microbial mat communities in streams in the McMurdo Dry Valleys. She completed her PhD in 2011 and is currently a post-doctoral scholar with Norman Pace at the University of Colorado.


Terry Bilinski (Legg), EBIO PhD graduate

Terry's dissertation work involved examining the organisms involved in arsenic cycling in Bangladesh aquifer sediments. She completed her PhD in 2013 and is currently an assistant professor at St. Edwards University in Austin.

Sean P. O'Neill, EBIO MA graduate

Sean investigated the change in the structure of microorganisms in a variety of primary successional environments, including the Mendenhall Glacier in Juneau, AK; the Puca Glacier, in Peru; and Mt. Baker, WA. He has been working as research associate at Palmer Station, Antarctica, since he completed his degree in May 2013.

Institute of Arctic and Alpine Research
Environmental Studies Program