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Dr. Peter M. Groffman

Microbial Ecologist | PhD, University of Georgia

Expertise
soil ecology, water quality

Profile (pdf)

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Peter Groffman studies how microbial processes impact gas exchange - particularly nitrogen - between the soil and air. His work encompasses rural and urban ecosystems, and is primarily centered at two of the National Science Foundation’s Long Term Ecological Research sites located in Hubbard Brook, New Hampshire and Baltimore, Maryland.

As a result of climate change, forests in the northeastern US are experiencing reduced winter snow cover. This change leaves the forest soil exposed to subfreezing temperatures for extended periods. Without a layer of insulating snow, important biological activity that usually continues throughout the winter stops. Freezing damages tender tree roots. Increased winter rain washes nitrogen and phosphorus - nutrients critical to tree growth - out of the soil, threatening forest productivity and water quality. Bare soils produce more nitrous oxide and consume less methane - both potent greenhouse gases. Understanding these processes will inform forest management as climate warms.

Urbanization is a global trend marked by increasing homogenization of the landscape; imagine the cookie cutter properties that characterize ‘suburbia’. Understanding landscape homogenization will help predict the impacts of urban land use change and its effects on carbon storage and nitrogen pollution, on multiple spatial scales.

Groffman was a Convening Lead Author for the third National Climate Assessment Chapter on Ecosystems, Biodiversity and Ecosystem Services.

Groffman is also a Professor at the City University of New York Advanced Science Research Center at the Graduate Center and the Brooklyn College Department of Earth and Environmental Sciences.

Band, Lawrence E., C.L. Tague, and Peter M. Groffman. 2001. “Forest Ecosystem Processes at the Watershed Scale: Hydrological and Ecological Controls of Nitrogen Export”. Hydrol. Process 15: 2013-28.
Nielsen, C. B., Peter M. Groffman, Steven P. Hamburg, Charles T. Driscoll, Timothy J. Fahey, and J.P. Hardy. 2001. “Freezing Effects on Carbon and Nitrogen Cycling in Soils from a Northern Hardwood Forest”. Soil Sci. Soc. Am. J. 65: 1723-30.
Verchot, L. V., Z. Holmes, L. Mulon, Peter M. Groffman, and Gary M. Lovett. 2001. “Gross Versus Net Rates of N Mineralization and Nitrification As Indicators of Functional Differences Between Forest Types”. Soil Biol. Biochem. 33: 1889-1901.
Rosenblatt, A.E., Arthur J. Gold, M.H. Stolt, and Peter M. Groffman. 2001. “Identifying Riparian Sinks for Watershed Nitrate Using Soil Surveys”. J. Environ. Qual. 30: 1596-1604.
Gold, Arthur J., Peter M. Groffman, Kelly Addy, D.Q. Kellogg, M.H. Stolt, and A.E. Rosenblatt. 2001. “Landscape Attributes As Controls on Groundwater Nitrate Removal Capacity of Riparian Zones”. J. Am. Water Resour. Assoc 37: 1457-64.
Bohlen, Patrick J., Peter M. Groffman, Timothy J. Fahey, Charles T. Driscoll, and T.G. Siccama. 2001. “Plant-Soil-Microbial Interactions in a Northern Hardwood Forest”. Ecology 82: 965-78.
Mitsch, W. J., J.W. Day Jr., J.W. Gilliam, Peter M. Groffman, D.L. Hey, G.W. Randall, and N. Wang. 2001. “Reducing Nitrogen Loading to the Gulf of Mexico from the Mississippi River BasIn: Strategies to Counter a Persistent Ecological Problem”. BioScience 51: 373-88.
Groffman, Peter M., Charles T. Driscoll, Timothy J. Fahey, J.P. Hardy, Ross D. Fitzhugh, and G.L. Tierney. 2001. “Colder Soils in a Warmer World: A Snow Manipulation Study in a Northern Hardwood Forest Ecosystem”. Biogeochemistry 56: 135-50.
Jacinthe, P.A., and Peter M. Groffman. 2001. “Silicone Rubber Sampler to Measure Dissolved Gases in Waters”. Soil Biol. Biochem. 33: 907-12.
Groffman, Peter M., Charles T. Driscoll, Timothy J. Fahey, J.P. Hardy, Ross D. Fitzhugh, and G.L. Tierney. 2001. “Effects of Mild Winter Freezing on Soil Nitrogen and Carbon Dynamics in a Northern Hardwood Forest”. Biogeochemistry 56: 191-213.
Hardy, J.P., Peter M. Groffman, Ross D. Fitzhugh, K.S. Henry, T.A. Welman, J.D. Demers, Timothy J. Fahey, Charles T. Driscoll, G.L. Tierney, and S.S. Nolan. 2001. “Snow Depth Manipulation and Its Influence on Soil Frost and Water Dynamics in a Northern Hardwood Forest”. Biogeochemistry 56: 151-74.
Steinhart, G.S., Gene E. Likens, and Peter M. Groffman. 2000. “Denitrification in Stream Sediments in Five Northeastern (USA) Streams”. Verh. Int. Ver. Limnol. 27: 1331-36.
Groffman, Peter M., R. Brumme, K. Butterbach-Bahl, K.E. Dobbie, A.R. Mosier, D. Ojima, H. Papen, W.J. Parton, K.A. Smith, and C. Wagner-Riddle. 2000. “Evaluating Annual Nitrous Oxide Fluxes at the Ecosystem Scale”. Global Biogeochem. Cycles 14: 1061-70.
Connors, L. M., E. Kiviat, Peter M. Groffman, and Richard S. Ostfeld. 2000. “Muskrat (Ondatra Zibethicus) Disturbance to Vegetation and Potential Net Nitrogen Mineralization and Nitrification Rates in a Freshwater Tidal Marsh”. Am. Midl. Nat. 148: 53-63. http://www.caryinstitute.org/reprints/Connors_et_al_2000_Am_Midland_Naturalist_143_53-63.pdf.
Groffman, Peter M., Arthur J. Gold, and Kelly Addy. 2000. “Nitrous Oxide Production in Riparian Zones and Its Importance to National Emission Inventories”. Chemosphere - Global Change Sci. 2: 291-99.
Gold, Arthur J., Peter M. Groffman, Kelly Addy, D.Q. Kellogg, and A.E. Rosenblatt. 2000. “The Role of Landscape Setting in Riparian Groundwater Nitrate Removal”. In P. J. Wiggington, Jr. And R. L. Beshta (eds.). Riparian Ecology and Management in Multi-Land Use Watersheds; Proceedings, 113-17. American Water Resources Association, Middleburg, Virginia.
Van Hoewyk, D., Peter M. Groffman, E. Kiviat, G. Mihocko, and G. Stevens. 2000. “Soil Nitrogen Dynamics in Organic and Mineral Soil Fens in Eastern New York”. Soil Sci. Soc. Am. J. 64: 2168-73.
Groffman, Peter M., and Clive G. Jones. 2000. “Soil Processes and Global Change: Will Invertebrates Make a Difference?”. In D. C. Coleman and P. F. Hendrix (eds.). Invertebrates As Webmasters in Ecosystems, 313-26. CAB International, Oxon, UK, and New York, NY.
Frank, D. A., Peter M. Groffman, R.D. Evans, and B.F. Tracy. 2000. “Ungulate Stimulation of Nitrogen Cycling in Yellowstone Park Grasslands”. Oecologia 123: 116-23.
Robertson, G. P., D. Wedin, Peter M. Groffman, J.M. Blair, E.A. Holland, Knute J. Nadelhoffer, and D. Harris. 1999. “Soil Carbon and Nitrogen Availability: Nitrogen Mineralization, Nitrification and Carbon Turnover”. In G. P. Robertson, C. S. Bledsoe, D. C. Coleman, and P. Sollins (eds.). Standard Soil Methods for Long Term Ecological Research, 258-71. Oxford University Press, New York.