University of Georgia
Room 708, Biological Sciences Bldg.
Athens, GA 30602
Fax: (706) 542-3363
Ph.D. - Duke University (Terrestrial Community & Ecosystem Ecology)
MEM - Duke University (Conservation Ecology)
B.S., B.A. - University of Chicago (Biochemistry & Evolutionary Ecology)
I use experimental, observational and quantitative modeling approaches to investigate population, community and ecosystem processes across local and regional scales. In particular, my research focuses on i) impacts of global change on forest composition, succession and species distributions, ii) fundamental mechanisms that maintain species coexistence, iii) feedbacks between altered species composition and biogeochemical processes, iv) ecosystem consequences of geographical genetic variability in plant responses to environmental change, and v) potential plant and soil feedbacks to the climate system. These diverse approaches reflect my desire to address fundamental ecological questions that are relevant to the environmental challenges we face today and will undoubtedly deal with in the future. My research involves asking basic questions motivated by ecological theory, and then integrating empirical data with quantitative analyses to forecast responses of plant populations, communities and ecosystems to changing environments. My interests are connected by the pervasive goal of understanding fundamental relationships between ecological processes, how these relationships vary over space and time, and the effects of environmental change on individual levels of biocomplexity as well as on systems in their entirety. I have conducted research in southern (Duke Forest; Coweeta Hydrologic Laboratory; Pisgah, Nantahala, Kisatchie and Apalachicola National Forests) and northeastern (Harvard Forest) temperate forest systems, and have also worked in southern Appalachian seepage bogs, high-elevation spruce-fir forests, fire-dependent longleaf pine savannas, and Swedish arctic shrub communities. I look forward to continuing research in forests and other ecosystems, and in expanding my current population, community and biogeochemical work in ecosystems of the United States and abroad.
2012 NSF Emerging Frontiers - Macrosystem Biology - This project investigates the responses of forests (and in our FL site, savanna) ecosystems to spatio-temporal variaitons in annual changes in climate/weather patterns. We study weather/climate impacts on forest tree demography (growth, survivorship, fecundity) as well as additional projects on soil seed banking and mycorrhizal colonization. With our team of PI's we have sites established along the East Coast (NH through FL) as well as tropical forests in Puerto Rice, Costa Rica, and the Andes. ($550 k)
2012 NSF RAPID - We examined the effects of an unprecedented oak-eating caterpillar outbreak on the responses of soil biogeochemistry to climate change at our soil warming research site in Whitehall Forest (the Whitehall Forest Warming Facility, WFWF). We are finding in our nutrient-poor, low-carbon soils that insect organic inputs to the soils through fraas and throughfall aditions has a much larger effect on net nitrogen mineraliztion than does soil warming. ($164K)
2008 NSF Coweeta Long Term Ecological Research Renewal Grant - Southern Appalachia on the Edge - Exurbanization and Climate Interaction in the Southeast. ($7.4 million)
2007 DOE - soil and air warming at Harvard Forest (MA) and Duke Forest (NC) to detmine how eastern US forests will look and function in the next century & beyond ($2.2 million)
2007 UGA - soil and air warming at Whitehall Forest (GA) (to expand the above research into the Deep South)
1997 DOE - terrestrial ecosystem responses to global change ($290 K)
2010 Outstanding Teaching Award, University of Georgia
2002 Buell Award (Ecological Society of America's Award for the best student presentation)
1993 U.S. Forest Service Science & Mathematics Award (for Best Master's Project at the Duke Nicholas School)
1991-1993 Duke Fellow with The Nature Conservancy (Master's Fellowship to formulate ecologically-based reserve design methods)
1991 Mellinger Grant for Academic Excellence (University of Chicago)
Ecological Society of America
American Geophysical Union
American Association for the Advancement of Science
Society of Conservation Biology
British Ecological Society
Mohan, J.E., C. Cowden, P. Baas, A. Dawadi, P.T. Frankson, K. Helmick, E. Hughes, S. Khan, A. Lang, M. Machmuller, M. Taylor, C.A. Witt. 2014. Mycorrhizal fungi mediation of terrestrial ecosystem responses to global change: mini-review. Invited review Fungal Ecology 10: 3-19
Baas, P., J.E. Mohan, D. Markewitz, J. Knoepp. 2014. Assessing Heterogeneity in Soil Nitrogen Cycling: A Plot-Scale Approach. Soil Science Society of America 78 (S): S237-S247.
Clark, J.S., J.M. Melillo, J.E. Mohan, C. Salk. 2014. The timing of warming that controls onset of the growing season. Global Change Biology 20(4): 1136-1145.
Anderson-Teixeira, K., A.D. Miller, J.E. Mohan, T.W. Hudiburg, B.D. Duval. E.H. DeLucia. 2013. Altered dynamics of forest recovery under a changing climate. Invited review Global Change Biology 19(7): 2001-2021.
Coyle, D.W., J. Pickering, K.A. Dryer, F.R. Lehman*, J.E. Mohan, K.J.K. Gandhi. 2013. Dynamics of an Unprecedented Outbreak of Two Native Moth Species, Cissusa spadix and Phoberia atomaris (Lepidoptera: Noctuidae), on Oak Trees (Quercus spp.) in the Southeastern U.S.A. "Featured Article" American Entomologist 59(2): 82-94.
Butler, S.M., J.M. Melillo, J.E. Johnson, J.E. Mohan, P.A. Steudler, H. Lux, E. Burrows, R.M. Smith, C.I. Vario, I. Scott, TD. Hill, N. Apontes, and F. Bowles. 2012. Soil warming alters nitrogen cycling in a New England forest: implications for ecosystem function and structure. Oecologia 168(3): 819-828. DOI 0.1007/s00442-011-2133-7.
Melillo, J.M., S. Butler, J.Johnson, J. Mohan, P.A. Steudler, H. Lux, E. Burrows, F. Bowles, R. Smith, T. Hill, C.Vario, A.J. Burton,Y. Zhou, J. Tang. . 2011. Soil warming, carbon-nitrogen interactions and forest carbon budgets. Proceedings of the National Academy of Sciences 108(23): 9508-9512.
Zhou, Y., J. Tang, J. Melillo, S. Butler, S., and J. Mohan,. 2011. Root standing crop and chemistry after six years of soil warming in a temperate forest. Tree Physiology 31: 707-717.
Mohan, J.E., R. Cox, and L. Iverson. 2009. Northeastern forest composition and carbon dynamics in a future, warmer world. Canadian Journal of Forest Research 39: 213-230.
Bradford, M., Wallenstein, M., Allison, S., Treseder, K, Frey, S, Watts, B., Davies, C, Maddox, T, Melillo, J, Mohan, J, Reynolds, J. 2009. Decreased mass specific respiration under experimental warming is robust to the microbial biomass method employed. Ecology Letters 12: E12-E15.
Rustad, L.E., J.C. Campbell, R.C. Cox, M. DeBlois, J.S. Dukes, T.G. Huntington, A.H, Magill, J.E. Mohan, J. Pontius, A.D. Richardson, N.L. Rodenhouse, M.R. Watson, and N. Willard. 2009. NE Forests 2100: Evaluating climate-driven changes in northeastern North American forests. Canadian Journal of Forest Research 39:1-10.
Bradford, M.A., C.A. Davies, S.D. Frey, T.R. Maddox, J.M. Melillo, J.E. Mohan, J.F. Reynolds, K.K. Treseder, and M.D. Wallenstein. 2008. Thermal adaptation of soil microbial respiration to elevated temperature. Ecology Letters, in press. Doi: 10.1111/j.1461-0248.2008.01251.x
Wang, X. and J.E. Mohan. 2008. Effects of global changes on weeds. CAB Reviews: Perspectives in Agriculture, Veterinary Science, Nutrition and Natural Resources, invited review, in press. Doi: 10.1079/PAVSNNR20083067.
Mohan, J.E., R. Cox, and L. Iverson. 2008. Northeastern forest compositions and productivity in a future, warmer world. Canadian Journal of Forest Research. In press.
Mohan, J.E., L.H. Ziska, W.H. Schlesinger, R.B.Thomas, R.C. Sicher, K.George, J.S. Clark. 2008. Biomass and toxicity responses of poison ivy (Toxicodendron radicans) to elevated atmospheric CO2: Reply. Ecology 89(2): 585-587.
Mohan, J.E., J.S. Clark, W.H. Schlesinger. 2007. Long-term CO2 enrichment of a forest ecosystem: implications for forest regeneration and succession. Ecological Applications 17(4): 1198-1212.
Ziska L.H., Sicher R.C., George K., Mohan J.E. 2007. Rising atmospheric carbon dioxide and potential impacts on the growth and toxicity of poison ivy (Toxicodendron radicans). Weed Science 55: 288-292
Mohan, J.E., L.H. Ziska, W.H. Schlesinger, R.B.Thomas, R.C. Sicher, K.George, J.S. Clark. 2006. Biomass and toxicity responses of poison ivy (Toxicodendron radicans) to elevated atmospheric CO2. Proceedings of the National Academy of Sciences 103(24): 9086-9089.(covered in >130,000 news entries on Google News.com)
Ellison, A.M., M.S. Bank, B.D. Clinton, E.A. Colburn, K. Elliott, C. Ford, D.R. Foster, B.D. Kloeppel, J.D. Knoepp, G.M. Lovett, J.E. Mohan, D.A. Orwig, N.L. Rodenhouse, W.V. Sobczak, K.A. Stinson, P. Snow, J.K. Stone, C.M. Swan, J. Thompson, B. Von Holle, and J.R. Webster. 2005. Loss of foundation species: consequences for the structure and dynamics of forested ecosystems. Frontiers in Ecology and Evolution 9(3): 479-486.
Knepp, R.G., J.G. Hamilton, J.E. Mohan, A.R. Zangerl, M.R. Berenbaum, and E H. DeLucia. 2005. Elevated CO2 reduces leaf damage by insect herbivores in a forest community. New Phytologist 167(1): 207-218
Mohan, J.E., J.S. Clark, and W.H. Schlesinger. 2004. Genetic variation in germination, growth, and survivorship of red maple in response to subambient through elevated atmospheric CO2. Global Change Biology 10: 233-247.
Schlesinger, W.H., J.S. Clark, J.E. Mohan, and C.D. Reid. 2001. Global Environmental Change: Effects on Biodiversity. Pg. 175-223 IN: M. Soule and G. Orians (eds.) Conservation Biology: Research Priorities for the Next Decade. Island Press. Washington, D. C., USA.
Clark, J.S., B. Beckage, J. HilleRisLambers, I. Ibanez, S. LaDeau, J. McLachlan, J. Mohan, and M. Rocca. 2001. The Role of Dispersal in Plant Migration. IN: H. A. Mooney and J. Canadell (eds.) Encyclopedia of Global Environmental Change, Volume 3. John Wiley & Sons, Inc. New York, NY.
Clark, J.S., B. Beckage, P. Camill, B. Cleveland, J. HilleRisLambers, J. Lichter, J. McLachlan, J. Mohan, and P. Wycoff. 1999. Interpreting recruitment limitation in forests. American Journal of Botany 86:1-16.
Delucia, E.H., JG. Hamilton, S.L. Naidu, R.B. Thomas, JA. Andrews, A. Finzi, M.Lavine, R.Matamala, J.E. Mohan, G.R. Hendrey, and W.H. Schlesinger. 1999. Net primary production of a forest ecosystem with experimental CO2 enrichment. Science 284:1177-1179.
I am fascinated by impacts of past and future global changes on plant population dynamics, community interactions and ecosystem functioning. I continue to study climate feedbacks mediated by vegetation and soils, and ecological consequences of geographical genetic variation in plant responses to changing environmental factors.