How do we best use our understanding of the way the world works to turn around and feed the world?


| Agroecological Nutrient Dynamics |
| Data Visualization |
| Soil Hydrologic Modeling |
| Cropping Systems Diversification |
| Sustainable Agriculture |
| Spatial Data Analysis |
| Soil Controls on Landscape Productivity |


I’m currently a graduate research assistant in the Poffenbarger lab at the University of Kentucky, studying nutrient fluxes and crop yields in relation to cover crop implementation. I received my B.S. in Soil and Water Sciences from Montana State University in 2017. My primary research interest revolves around a core theme: "How do we leverage our understanding of ecosystem dynamics, soil system heterogeneity, and agricultural productivity into the manifestation of a more sustainable food system?" This theme has come about through work in a number of natural and managed environments, including assessing the source of streamflow generation in mountainous watersheds, investigating the efficacy of cover cropping rotations for improved soil carbon retention, working to understand the role natural disturbance regimes dictate carbon storage, and improving management strategies for organic Western agricultural systems. Moving forward, my focus surrounds landscape geomorphologic controls on soil water movement, nutrient cycling, and crop yields, using a variety of field based measures and soil-crop system models. 

My interests are largely driven by the inherit multi-disciplinary nature of soil science, and the intricacies of the soil system from the microscopic scale up to a landscape and global level.  I'm passionate about the role soil sustainability and management needs to play in strengthening global food security in the coming decades, and the ways that an integrated soil-crop system perspective can lead to improved yield coupled with improved sustainability. With a background in landscape pedology and biogeochemistry, as well as geographic information science and modeling, I attempt to bring an ecosystem science point of view to an agricultural framework.

Beyond soil science, I also enjoy riding my bike, cooking, fishing, reading, and backpacking. If you have any interest in possible collaborations, or questions and ideas about my work and it’s implications, please reach out to me!

Research Experience

Graduate Research Assistant -Poffenbarger Agroecological Nutrient Cycling Lab (UK)

January 2018 - Current

Research Associate -Ewing Soil Biogeochemistry Lab (MSU)

November 2016 - December 2018

Biological Science Technician -  USGS Geosciences and Environmental Change Science Center

May 2016 - August 2016

Research Assistant - Menallad Integrate Cropland Weeds Management Lab (MSU)

May 2015 - May 2016

Research Assistant - Hartshorn Soil Interrogation Lab (MSU)

January 2015 - May 2016

Selected Presentations

Leuthold, S., Ewing, S.A., Payn, R., Miller, F., Paces, J. (2018) Longitudinal Patterns in Stream Stable Isotope Chemistry along a Snowmelt Driven Headwater Suggest Seasonally Dynamic Connectivity between Proximal Streamflow Generation Sources. Oral presentation presented at AGU 2018 Fall Meeting. 11 December, Washington, DC.

Leuthold, S., Ewing, S.A., Payn, R., Miller, F., Klassen, J., Paces, J., (2018) Where should we begin; a conversation between soils and streams in Hyalite Canyon. Oral presentation presented at MSU LRES Research Colloquium. 16 April, Bozeman, MT. (2nd place best student oral presentation) 

Leuthold, S., Ewing, S.A., Payn, R., Miller, F., Klassen, J., Paces, J., (2017) Using stable liquid water isotopes to understand sources of stream flow generation in a mountainous headwaters catchment. Poster presented at 25th Annual NSF EPSCoR National Conference. 5-8 November, Missoula, MT.

Leuthold, S., Ewing, S.A., Payn, R., Miller, F., Klassen, J., (2017) Stable Water Isotopes in the Hyalite Canyon Watershed. Montana Institute on Ecosystems Intern Presentations. 19 September, Bozeman, MT.

Ewing, S.A., Miller, F., Payn, R., Leuthold, S., Paces, J., (2017) Using weathering and solute geochemistry to understand sources of base flow water supply across mountain-basin transitions in the Upper Missouri Watershed. Poster presented at Catchment Science: Interactions of Hydrology, Biology and Geochemistry Gordon Research Conference. 24 - 25 June, Lewistown, ME.


Leuthold, S.J., Ewing, S.A., Payn, R., Miller, F., Paces, J. (In-Prep) Seasonality of proximal area subsurface flow contributions along a mountain headwater stream (Hyalite Canyon, MT). In preparation for submission to Hydrologic Processes.

Leuthold, S.J., Ewing, S.A., Sigler, W., Gobrogge, C., Jones, C. (In-Prep) A simple bucket model
approach to understanding water isotope and inorganic solute flux through dryland
agricultural systems. In preparation for submission to Agricultural Water Management.

Miller, F., Ewing, S.A., Payn, R., Leuthold, S.J., Paces, J. (In-Review) Using weathering and solute
geochemistry to understand the sources of base flow in Hyalite Canyon, MT. In preparation for submission to Water Resource Research.