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 nutrient profiles 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.
The 2018 CERG crew, with me giving Thumbs Up For Science!
Iron in terrestrial systems
This 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 and the evolution of terrestrial life. Finally, I am interested in iron cycling in deserts and am working with biological soil crusts to address this topic.
Field sites: Utah; Wyoming; Iceland; really, anywhere with soils, modern or fossil!
Terrestrial paleoclimate reconstructions
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., in prep.)
I am also working on the Early Eocene Climatic Optimum (EECO), a period of abrupt warming around 56 Ma, as recorded in floodplains in Wyoming.
Field sites: Wyoming, India
SE Michigan wetlands soil chemistry
In addition to my own research, I am working with an undergraduate research assistant to determine seasonal changes in nutrient cycling in wetland soils in Michigan; this work is part of the University of Michigan’s Undergraduate Research Opportunity Program and was sparked by field trips led as part of the Soils & Surface Processes class taught with my adviser in Fall 2017.
(UROP 2016 project: Reconstructing vegetation in Wyoming at the EECO using carbon isotopes.)