I am a Ph.D. student in geochemistry in the University of Michigan’s Department of Earth & Environmental Sciences. My research interests involve iron and other essential nutrients in soils, past and present: what controls their presence and availability in soils? How have their concentrations changed over time? What can we tell about past environments by studying iron in fossil soils?
The answers to these questions lie in the “critical zone” – the interface of the physical earth, the atmosphere, and living organisms at Earth’s surface. By studying modern environments, we can gain a better understanding for the complex processes and mechanisms at play in soils, and what signatures they might leave behind for us to pull apart when they are found in the rock record. Then, by studying past environments using fossil soils (paleosols), we can learn about how terrestrial ecosystems reacted to climate changes through time. Taken together, these approaches help us comprehensively understand essential nutrients in soils and how they might be altered by climate change. I hope that my research can inform models for agriculture and soil fertility so that we can better predict how global food production and distribution may change.
Continental Environments Research Group (CERG)
Advisor: Nathan Sheldon
Current projects: Iron in terrestrial systems
My ongoing work focuses on constraining the relationship between the concentration and type of iron oxides found in different soil orders under varying climatic regimes, using a novel combination of chemical extractions and analytical techniques. (AGU 2016). I am currently working to characterize a large suite of modern soils’ iron content, and exploring potential relationships with climatic variables. I am also interested in terrestrial iron and its ties to the oxygenation of the atmosphere. Finally, I am interested in iron cycling in deserts and am working with biological soil crusts to address this topic. I plan to expand my work to include magnetic analyses, and potentially a plant growth experiment to explore iron uptake and soil nutrients.
In addition to my own research, I am working with an undergraduate student to define iron contents of wetland soils in Michigan; this work is part of the University of Michigan’s Undergraduate Research Opportunity Program. (Past projects with UROP: Reconstructing vegetation in Wyoming at the EECO using carbon isotopes.)
Field sites: Utah; Wyoming; Iceland; really, anywhere with soils, modern or fossil!
Current projects: Paleoclimate reconstruction
In addition to iron-specific work, I am interested in broad terrestrial paleoclimate reconstructions for periods of rapid climate change. In 2017, I visited India to sample paleosols formed at the edge of the Deccan Traps before, during, and after the end-Cretaceous extinction event, for the purpose of paleoclimate reconstruction (GSA, October 2017; Dzombak et al. 2017, in prep.) I am also working on the Early Eocene Climatic Optimum (EECO), a period of abrupt warming around 56 Ma.
Field sites: Wyoming, India