Scientists & Staff
My scientific interests focus on understanding how hydrological and biogeochemical processes interact in ecosystems. I study how source variation and landscape processes affect the flow of water and solutes through the environment using traditional hydrological analyses, high-frequency chemical sampling, and isotopic tracers.
I am a research hydrologist with the USDA Forest Service in Grand Rapids, MN. I devote portions of my time to research at the Marcell Experimental Forest (MEF) and national-scale syntheses of data from catchment studies on Experimental Forests and Ranges of the USDA Forest Service. At the MEF, I am co-leader of research planning and co-lead scientist on hydrological and biogeochemical research. I have developed a comprehensive research program that builds upon the 50-year legacy of research at this site. The MEF research watersheds were established to study the ecology and hydrology of peatlands and uplands along the southern fringe of the boreal zone. Using extensive resources at the field site, I pursue research related to the effects of nitrogen pollution on ecosystem functions, carbon cycling in peatlands, understanding effects of climate variability, interactions of dissolved organic matter with mercury and other trace metals, and quantifying effects of landscape disturbance on water and solutes yields. I am a participant in the SPRUCE Experiment (Spruce and Peatland Response Under Climatic and Environmental change), a large-scale, experiment in which above- and below-ground temperatures will be manipulated in a black spruce ? Sphagnum bog at the MEF.
I participate and co-lead data synthesis efforts on catchment studies to investigate stream chemistry responses to climate change, atmospheric deposition, natural disturbance, and forest management practices. The intent of these studies is to broaden understanding to national and global scales.
At the Sleepers River Research Watershed in northeastern Vermont, I have been exploring how sources of stream nitrate and dissolved organic matter (DOM) vary among events, seasons, and years. My research in the northeastern USA also includes studies of nitrate sources, DOM dynamics, and effects of biogeochemical cycles during winter on water and solutes yields from catchments that span the region from New York to Maine.
I also study how the direction, magnitude, and variability of groundwater seepage influences biogeochemical cycles in lakes and wetlands. With past work, I have explored the effects of lakeshore seepage on pore water biogeochemistry, plant communities, and brook trout redds in lakes of the Adirondack Mountains of New York. In several new studies, I work with other researchers to quantify effects of groundwater seepage on lake trophic status.
I collaborate with a broad range of research scientists, graduate students, and undergraduate students on projects at the MEF, across the USA, and abroad. My position as a Forest Service scientist and being adjunct faculty at the University of Minnesota and Bemidji State University allow me to be highly involved with graduate student and postdoctoral research.
With future projects and collaborations, I will pursue research that:
- Quantifies rates of terrestrial and aquatic biogeochemical transformations to definitively pinpoint the landscape processes that affect water chemistry.
- Determines how sources, transformations, and transport processes interact to control nutrient availability within ecosystems.
- Quantifies how short-term processes that occur at discrete locations and times (the hotspots and hot moments of biogeochemical processes) are important when considered at the ecosystem level.
- Considers how to scale up understanding of hydrological and biogeochemical processes from plot level studies and point monitoring locations to larger landscape units.
- Establishes monitoring and experimental (manipulative) studies to identify how the timing, release, and cycling of solutes in catchments is affected by climatic and land use / land cover changes.
Why This Research is Important
- State University of New York College of Environmental Science & Forestry, Ph.D. Forest and Natural Resources Management, 2008
- Cornell University, Department of Natural Resources, MS Program in Biogeochemistry & Global Change, 2000
- Susquehanna University, Department of Geological and Environmental Sciences, BS , 1997
- American Association for the Advancement of Science
- American Geophysical Union
- International Association of Hydrological Sciences
Awards & Recognition
- Northern Research Station Director’s Early Career Scientist Award, 2013
In recognition of exemplary contributions to the fields of biogeochemistry and hydrology across the US, and locally at the Marcell Experimental Forest. Your research on nitrogen and dissolved organic matter identifying sources, chemical transformations,
- Forest Service award for contributions to a strategic focus document on the Clean Air, 2008
Forest Service award for contributions to a strategic focus document on the Clean Air
Featured Publications & Products
- Argerich, A.; Johnson, S.L.; Sebestyen, S.D.; Rhoades, C.C.; Greathouse, E.; Knoepp, J.D.; Adams, M.B.; Likens, G.E.; Campbell, J.L.; McDowell, W.H.; Scatena, F.N.; Ice, G.G. 2013. Trends in stream nitrogen concentrations for forested reference catchments across the USA.
- Pellerin, Brian A.; Saraceno, John Franco; Shanley, James B.; Sebestyen, Stephen D.; Aiken, George R.; Wollheim, Wilfred M.; Bergamaschi, Brian A. 2012. Taking the pulse of snowmelt: in situ sensors reveal seasonal, event and diurnal patterns of nitrate and dissolved organic matter variability in an upland forest stream.
- Sebestyen, Stephen D.; Dorrance, Carrie; Olson, Donna M.; Verry, Elon S.; Kolka, Randall K.; Elling, Art E.; Kyllander, Richard. 2011. Long-term monitoring sites and trends at the Marcell Experimental Forest. Chapter 2..
- Sebestyen, Stephen D.; Verry, Elon S.; Brooks, Kenneth N. 2011. Hydrological responses to changes in forest cover on uplands and peatlands. Chapter 13..
- Urban, Noel; Verry, Elon S.; Eisenreich, Steven; Grigal, David F.; Sebestyen, Stephen D. 2011. Element cycling in upland/peatland watersheds Chapter 8..
- Vidon, Philippe; Allan, Craig; Burns, Douglas; Duval, Tim P.; Gurwick, Noel; Inamdar, Shreeram; Lowrance, Richard; Okay, Judy; Scott, Durelle; Sebestyen, Stephen. 2010. Hot spots and hot moments in riparian zones: Potential for improved water quality management.
- Sebestyen, Stephen D.; Boyer, Elizabeth W.; Shanley, James B. 2009. Responses of stream nitrate and DOC loadings to hydrological forcing and climate change in an upland forest of the northeastern United States.
- Sebestyen, Stephen D.; Shanley, James B.; Boyer, Elizabeth W. 2009. Using high-frequency sampling to detect effects of atmospheric pollutants on stream chemistry.
- Sebestyen, Stephen D.; Boyer, Elizabeth W.; Shanley, James B.; Kendall, Carol; Doctor, Daniel H.; Aiken, George R.; Ohte, Nobuhito. 2008. Sources, transformations, and hydrological processes that control stream nitrate and dissolved organic matter concentrations during snowmelt in an upland forest.
Publications & Products
- Sebestyen, Stephen D.; Shanley, James B.; Boyer, Elizabeth W.; Kendall, Carol; Doctor, Daniel H. 2014. Coupled hydrological and biogeochemical processes controlling variability of nitrogen species in streamflow during autumn in an upland forest.
- McGuire, Kevin J.; Sebestyen, Stephen D.; Ohte, Nobuhito; Elliott, Emily M.; Gomi, Takashi; Green, Mark B.; McGlynn, Brian L.; Tokuchi, Naoko. 2014. Merging perspectives in the catchment sciences: the US-Japan Joint Seminar on catchment hydrology and forest biogeochemistry.
- Vose, James M.; Ford, Chelcy R.; Laseter, Stephanie; Dymond, Salli; Sun, Ge; Adams, Mary Beth; Sebestyen, Stephen; Campbell, John; Luce, Charlie; Amatya, Devendra; Elder, Kelly; Heartsill Scalley, Tamara. 2012. Can forest watershed management mitigate climate change effects on water resources.
- Jones, Julia A.; Creed, Irena F.; Hatcher, Kendra L.; Warren, Robert J.; Adams, Mary Beth; Benson, Melinda H.; Boose, Emery; Brown, Warren A.; Campbell, John L.; Covich, Alan; Clow, David W.; Dahm, Clifford N.; Elder, Kelly; Ford, Chelcy R.; Grimm, Nancy B.; Henshaw, Donald L; Larson, Kelli L.; Miles, Evan S.; Miles, Kathleen M.; Sebestyen, Stephen D.; Spargo, Adam T.; Stone, Asa B.; Vose, James M.; Williams, Mark W. 2012. Ecosystem processes and human influences regulate streamflow response to climate change at long-term ecological research sites.
- Parsekian, Andrew D.; Slater, Lee; Ntarlagiannis, Dimitrios; Nolan, James; Sebestyen, Stephen D.; Kolka, Randall K.; Hanson, Paul J. 2012. Uncertainty in peat volume and soil carbon estimated using ground-penetrating radar and probing.
- Kolka, Randall K.; Sebestyen, Stephen D.; Bradford, John B. 2011. An evolving research agenda at the Marcell Experimental Forest. Chapter 3..
- Lyttle, Amy; Yoo, Kyungsoo; Hale, Cindy; Aufdenkampe, Anthony; Sebestyen, Stephen. 2011. Carbon-mineral interactions along an earthworm ivasion gradient at a sugar maple forest in northern Minnesota.
- Sebestyen, Stephen D.; Verry, Elon S. 2011. Effects of watershed experiments on water chemistry at the Marcell Experimental Forest. Chapter 14..
- Resner, Kathryn; Yoo, Kyungsoo; Hale, Cindy; Aufdenkampe, Anthony; Blum, Alex; Sebestyen, Stephen. 2011. Elemental and mineralogical changes in soils due to bioturbation along an earthworm invasion chronosequence in northern Minnesota.
- Verry, Elons S.; Brooks, Kenneth N.; Nichols, Dale S.; Ferris, Dawn R.; Sebestyen, Stephen D. 2011. Watershed hydrology. Chapter 7..
- Glynn, Pierre D.; Larsen, Matthew C.; Greene, Earl A.; Buss, Heather L.; Clow, David W.; Hunt, Randall J.; Mast, M. Alisa; Murphy, Sheila F.; Peters, Norman E.; Sebestyen, Stephen D.; Shanley, James B.; Walker, John F. 2009. Selected achievements, science directions, and new opportunities for the WEBB Small Watershed Research Program.
- Doctor, Daniel H.; Kendall, Carol; Sebestyen, Stephen D.; Shanley, James B.; Ohte, Nobuhito; Boyer, Elizabeth W. 2008. Carbon isotope fractionation of dissolved inorganic carbon (DIC) due to outgassing of carbon dioxide from a headwater stream.
- Ohte, N.; Sebestyen, S.D.; Kendall, C.; Shanley, J.B.; Wankel, S.D.; Doctor, D.H.; Boyer, E.W. 2004. Tracing sources of nitrate in snowmelt runoff using a high-resolution isotopic technique.