Nigel Roulet

Professor and Department Chair
Nigel Roulet
Contact Information
Email address: 
nigel.roulet [at]
Research areas: 
Ecosystem biogeochemistry

Distinguished James McGill Professor of Biogeosciences
Trottier Institute for Science and Public Policy (TISPP) Fellow

Welcome to my home page. I have prepared this page for undergraduates, prospective graduate students and post-doctoral research fellows, and others who have similar interests to mine. After looking over my page if you have any questions please do not hesitate to contact me either by e-mail or telephone.

Current research: 

The research conducted in my group is at the interface among hydrological, climatological, biogeochemical, and ecological systems. I am interested in understanding how biogeochemical transformations and ecosystem dynamics respond to changes in hydrological and climatological settings and forcings. My work broadly fits under the umbrella of earth system science, biogeochemistry and ecohydrology. I employ observational, experimental, and modelling approaches to help us resolve fundamental questions related to process and pattern. Geographically the ecosystems attracting my current interest are located in the cool-temperate, boreal, subarctic and arctic ecoclimatic regions. The ecosystems of focus are wetlands, particularly peatlands, and forests. I conduct research in North America and Europe.

At the present time the primary foci of my research is on the carbon, energy and water balances of northern peatlands and how land-use and climate change will affect the stores and exchanges in these ecosystems. I am currently measuring and simulating to effects the extraction of peat for horticutlural purposes has on peatland function; better defining the role of heteorotrophic respiration on ecosystem respiration from peatlands; determining the inter-annual variability of the water balance of a cool-temperate raised bog; and determining the sources of CO2 to Sphagnum moss.

Current opportunities for graduate and post-doctoral studies

There are lots of opportunities for graduate students and post-doctoral research fellows to work on within my research program. The Department of Geography offers both a M.Sc. and a Ph.D. in physical geography. The program has developed specializations in climate and global change and ecosystem biogeochemistry and hydrology. In addition to the programs in Geography there are a number of allied programs in Atmosphere and Ocean Sciences and the Faculty of Agricultural and Environmental Sciences on the Macdonald Campus of McGill University. For information on the graduate program in the Department of Geography please see: Graduate Information

Graduate students in our program normally receive between $18,000 to $22,000 per year of support from a combination of research and teaching assistantships, stipends and external and internal scholarships. In addition to Departmental support and support directly from supervisors there are a number of funding opportunities for graduate students through the Faculty of Graduate Studies. If you are interested in any of the research outlined above or other aspects of the links among hydrology, climate, biogeochemistry and ecosystems do not hesitate to contact me. I recommend you contact me early in the fall semester. For prospective students who are located in north eastern North America I encourage to come and visit.


I teach both undergraduate and graduate courses in the Department of Geography and the McGill School of Environment (MSE). The courses I am often involved in are:

  • GEOG 203: Environmental systems
  • GEOG 322: Environmental hydrology
  • GEOG 401: Socio-environmental systems: theory and simulations
  • GEOG 505: Global biogeochemical cycles
  • GEOG 601: Advanced environmental systems modelling
  • Ph.D. McMaster University
  • B.Sc., M.Sc. Trent University

Awards and Distinctions:

2014 Fellow of the Royal Society of Canada, Academy of Sciences

Moore and Roulet (1992) GRL selected by the editors as a top 40 paper published in Geophysical Research Letters in the last 40 years.

2010 Mer Bleue Conservation Award (with Moore, Humphreys and Lafleur)

2009 The American Geophysical Union Award for Excellence in Reviewing (Global Biogeochemical Cycl.)

2009 Queen Mary University London, Department of Geography Distinguished Visitor (March)

2009 McGill Alumni Association award for Public Education

2007 Chapter contributing author to the 2007 Nobel Peace Prize winning 2007 Intergovernmental Panel on Climate Change Group I Report – The Science of Climate Change (AR4).

2000 The American Geophysical Union Award for Excellence in Reviewing (Global Biogeochemical Cycl.)

Selected publications: 

Papers in Refereed Journals over the last five years

  1. Verbeke, B. A., L. J. Lamit, E. A. Lilleskov, S. B. Hodgkins, N. Basiliko, E. S. Kane, R. Andersen, R. R. E. Artz, J. C. Benavides, B. W. Benscoter, W. Borken, L. Bragazza, S. M. Brandt, S. L. Bräuer, M. A. Carson, D. Charman, X. Chen, B. R. Clarkson, A. R. Cobb, P. Convey, J. d. Á. Pasquel, A. S. Enriquez, H. Griffiths, S. P. Grover, C. F. Harvey, L. I. Harris, C. Hazard, D. Hodgson, A. M. Hoyt, J. Hribljan, J. Jauhiainen, S. Juutinen, K.-H. Knorr, R. K. Kolka, M. Könönen, T. Larmola, C. K. McCalley, J. McLaughlin, T. R. Moore, N. Mykytczuk, A. E. Normand, V. Rich, N. Roulet, J. Royles, J. Rutherford, D. S. Smith, M. M. Svenning, L. Tedersoo, P. Q. Thu, C. C. Trettin, E.-S. Tuittila, Z. Urbanová, R. K. Varner, M. Wang, Z. Wang, M. Warren, M. M. Wiedermann, S. Williams, J. B. Yavitt, Z.-G. Yu, Z. Yu and J. P. Chanton. Latitude, Elevation, and Mean Annual Temperature Predict Peat Organic Matter Chemistry at a Global Scale. Global Biogeochemical Cycles 36(2): e2021GB007057. 2022
  2. He, H., T. Moore, E. R. Humphreys, P. M. Lafleur and N. T. Roulet. "Water level variation at a beaver pond significantly impacts net CO2 uptake of a continental bog." Hydrol. Earth Syst. Sci. Discuss. 2021: 151223, 1-26,, 2022.
  3. Shao,S. ,Wu, J., He, H., and NT Roulet. Integrating McGill Wetland Model (MWM) with Peat Cohort Tracking and Microbial Controls, Science of the Total Environment, Science of the Total Environment, 806, 151223,, 2022.

  4. Rankin. T., Rouet, NT., and TR Moore. Controls on autotrophic and heterotrophic respiration in an ombrotrophic bog. Biogeosciences, 19, 3285-33033,, 2022.

  5. Harris, L. I., K. Richardson, K. A. Bona, S. J. Davidson, S. A. Finkelstein, M. Garneau, J. McLaughlin, F. Nwaishi, D. Olefeldt, M. Packalen, N. T. Roulet, F. M. Southee, M. Strack, K. L. Webster, S. L. Wilkinson and J. C. Ray "The essential carbon service provided by northern peatlands." Frontiers in Ecology and the Environment 20(4):222-230 2022.

  6. Bear, Sydney; Seward, James; Lamit, L; Basiliko, Nathan; Moore, Tim; Lilleskov, Erik; Yavitt, Joseph; Schadt, Chris ; Smith, Dave ; McLaughlin, Jim; Siljanen, Henri; Mykytczuk, Nadia; Williams, Shanay; Roulet, Nigel; Harris, Lorna; Carson, Michael; Watmough, Shaun; Brauer, Suzanna. Beyond the usual suspects: methanogenic communities in eastern North American peatlands are also influenced by nickel and copper concentrations. FEMS Microbiology Letters 368, Issue 21-24,, 2021.

  7. Nugent, K. A., Strachan, I. B., Strack,M., Roulet, N. T., Ström, L., & Chanton,J. P. Cutover peat limits methane production causing low emission at a restored peatland. Journal of Geophysical Research: Biogeosciences,126, e2020JG005909. 2021.

  8. Heslop, J. K., J. K. Y. Hung, H. Tong, M. J. Simpson, F. M. Chapman, N. Roulet, M. J. Lafreni re and S. F. Lamoureux. "Diverging pond dissolved organic matter characteristics yield similar CO2flux potentials in a disturbed High Arctic landscape." Environmental Research Letters 16(4). 10.1088/1748-9326/abc913, 2021.

  9. Seward, J., M. A. Carson, L. J. Lamit, N. Basiliko, J. B. Yavitt, E. Lilleskov, C. W. Schadt, D. S. Smith, J. McLaughlin, N. Mykytczuk, S. Willims-Johnson, N. Roulet, T. Moore, L. Harris and S. Bräuer. "Peatland Microbial Community Composition Is Driven by a Natural Climate Gradient." Microbial Ecology 80(3): 593-602. 10.1007/s00248-020-01510-z, 2020.

  10. Helbig, M., J. M. Waddington, P. Alekseychik, B. D. Amiro, M. Aurela, A. G. Barr, T. A. Black, P. D. Blanken, S. K. Carey, J. Chen, J. Chi, A. R. Desai, A. Dunn, E. S. Euskirchen, L. B. Flanagan, I. Forbrich, T. Friborg, A. Grelle, S. Harder, M. Heliasz, E. R. Humphreys, H. Ikawa, P. E. Isabelle, H. Iwata, R. Jassal, M. Korkiakoski, J. Kurbatova, L. Kutzbach, A. Lindroth, M. O. Löfvenius, A. Lohila, I. Mammarella, P. Marsh, T. Maximov, J. R. Melton, P. A. Moore, D. F. Nadeau, E. M. Nicholls, M. B. Nilsson, T. Ohta, M. Peichl, R. M. Petrone, R. Petrov, A. Prokushkin, W. L. Quinton, D. E. Reed, N. T. Roulet, B. R. K. Runkle, O. Sonnentag, I. B. Strachan, P. Taillardat, E. S. Tuittila, J. P. Tuovinen, J. Turner, M. Ueyama, A. Varlagin, M. Wilmking, S. C. Wofsy and V. Zyrianov. "Increasing contribution of peatlands to boreal evapotranspiration in a warming climate." Nature Climate Change 10(6): 555-560. 10.1038/s41558-020-0763-7, 2020.

  11. Harris, L. I., N. T. Roulet and T. R. Moore. "Drainage reduces the resilience of a boreal peatland." Environmental Research Communications 2(6). 10.1088/2515-7620/ab9895, 2020

  12. Mzobe, P., Y. Yan, M. Berggren, P. Pilesjö, D. Olefeldt, E. Lundin, N. T. Roulet and A. Persson (2020). "Morphometric Control on Dissolved Organic Carbon in Subarctic Streams." Journal of Geophysical Research: Biogeosciences 125(9). e2019JG005348 DOI: 10.1029/2019JG005348

  13. Harris, L. I., T. R. Moore, N. T. Roulet and A. J. Pinsonneault. "Limited effect of drainage on peat properties, porewater chemistry, and peat decomposition proxies in a boreal peatland." Biogeochemistry 151(1): 43-62. 10.1007/s10533-020-00707-1, 2020.

  14. Helbig, M., J. M. Waddington, P. Alekseychik, B. Amiro, M. Aurela, A. G. Barr, T. A. Black, S. K. Carey, J. Chen, J. Chi, A. R. Desai, A. Dunn, E. S. Euskirchen, L. B. Flanagan, T. Friborg, M. Garneau, A. Grelle, S. Harder, M. Heliasz, E. R. Humphreys, H. Ikawa, P. E. Isabelle, H. Iwata, R. Jassal, M. Korkiakoski, J. Kurbatova, L. Kutzbach, E. Lapshina, A. Lindroth, M. O. Löfvenius, A. Lohila, I. Mammarella, P. Marsh, P. A. Moore, T. Maximov, D. F. Nadeau, E. M. Nicholls, M. B. Nilsson, T. Ohta, M. Peichl, R. M. Petrone, A. Prokushkin, W. L. Quinton, N. Roulet, B. R. K. Runkle, O. Sonnentag, I. B. Strachan, P. Taillardat, E. S. Tuittila, J. P. Tuovinen, J. Turner, M. Ueyama, A. Varlagin, T. Vesala, M. Wilmking, V. Zyrianov and C. Schulze. "The biophysical climate mitigation potential of boreal peatlands during the growing season." Environmental Research Letters 15(10). 104004, 10.1088/1748-9326/abab34, 2020.

  15. Harris, L. I., N. T. Roulet and T. R. Moore. "Mechanisms for the Development of Microform Patterns in Peatlands of the Hudson Bay Lowland." Ecosystems 23(4): 741-767. 10.1007/s10021-019-00436-z, 2020.

  16. Gong, J., Roulet, NT., Frolking. S., Peltola, H.,Laine. AM., Kokkonen, N., and E-S. Tuittila. Modelling the habitat preference of two key Sphagnum species in a poor fen as controlled by capitulum water retention. Biogeoscience 17, 5693-5719, / 2020

  17. Luan, J., J. Wu, S. Liu, N. Roulet and M. Wang (2019). "Soil nitrogen determines greenhouse gas emissions from northern peatlands under concurrent warming and vegetation shifting." Communications Biology 2(1).132, 10.1038/s42003-019-0370-1

  18. Nugent, K. A., I. B. Strachan, N. T. Roulet, M. Strack, S. Frolking and M. Helbig). "Prompt active restoration of peatlands substantially reduces climate impact." Environmental Research Letters 14(12): 124030, 10.1088/1748-9326/ab56e6, . 2019

  19. Arsenault, J., Talbot, J., Moore, T., Beauvais, M-P, Franssen, J., and N. Roulet. The Spatial Heterogeneity of Vegetation, Hydrology and Water Chemistry in a Peatland with Open-Water Pools. Ecosystems, 22, 1352-1367, 10.1007/s10021-019-00342-4, 2019

  20. Nugent, KA, Strachan. IB, Strack, M, Roulet, NT, and L Rochefort. Multi‐year net ecosystem carbon balance of a restored

  21. peatland reveals a return to carbon sink. Global Change Biology, 24:5751-5768, 10.1111/gcb.14449, 2018.

  22. Mzobe, P., M. Berggren, P. Pilesjö, E. Lundin, D. Olefeldt, N. T. Roulet and A. Persson. Dissolved organic carbon in streams within a subarctic catchment analysed using a GIS/ remote sensing approach" PLoS ONE 13(7), e0199608, 10.1371/journal.pone.0199608, 2018.

  23. Finlayson, C. M., G. T. Davies, W. R. Moomaw, G. L. Chmura, S. M. Natali, J. E. Perry, N. Roulet and A. E. Sutton-Grier (2018). The Second Warning to Humanity – Providing a Context for Wetland Management and Policy. Wetlands 38: 10.1007/s13157-018-1064-z, 2018.

  24. Kalacska, M., Arroyo-Mora, JP., Soffer, RJ., Roulet, NT., Moore, TR., Humphreys, E., Leblanc, G., Lucanus, O., and D. Inamdar. Estimating Peatland water table depth and net ecosystem exchange: A comparison between satellite and airborne imagery. Remote Sensing 10: Article number 687, 10.3390/rs10050687, 2018.

  25. Arroyo-Mora, JP., Kalacska, M., Soffer, RJ., Moore, TR., Roulet, NT., Juutinen, S., Ifimov, G. Leblanc, G., Lucanus, O., and D. Inamdar. Airborne hyperspectral evaluation of maximum gross photosynthesis, gravimetricwater content, and CO2 uptake efficiency of the Mer Bleue ombrotrophic peatland. Remote Sensing 10, Article number 565, 10.3390/rs10040565, 2018.

  26. Moomaw, WR., Chmura, GL., Davis, GT., Finlayson, CM., Middleton, BA., Natali, SM., Perry, JE., Roulet, NT., and AE. Sutton-Grier. The Relationship Between Wetlands and a Changing Climate: Science, Policy and Management. Wetlands 38: 183-20, 10.1007/s13157-018-1023-8, 2018.

  27. Harris, LH., Moore. TR., Roulet, NT., and AJ. Pinsonneault. Lichens: a limit to peat growth? J. Ecology, 106: 2301-2319, 10.1111/1365-2745.12975, 2018.

  28. Malhotra, A., NT Roulet, TR Moore and J. Limpens. Post-thaw variability in litter decomposition best explained by microtopography at an ice-rich permafrost peatland. Arctic, Antarctic, and Alpine Research 50: e1415622, 10.1080/15230430.2017.1415622, 2018.

  29. Wang, W., NT. Roulet, Y. Kim, IB. Strachan, P. del Giorgio, Y. T. Prairie, and A. Tremblay. Integrating aquatic and terrestrial biogeochemical model to predict effects of reservoir creation on CO2 emissions. Science of the Total Environment 612: 392-404, 10.1016/j.scitotenv.2017.08.203, 2018.

  30. Goud, E., Moore, TR. And NT Roulet. Predicting peatland carbon fluxes from non-destructive plant traits. Functional Ecology, 31: 1824-1833, 10.1111/1365-2435.12891, 2017.

  31. Wang, Z. and NT Roulet. Plant litter decomposition changes and comparison to peat with permafrost thaw in subarctic peatland. Plant and Soil 417:197-216, 10.1007/s11104-017-3252-7, 2017..

  32. Meng, L., Roulet, N., Qianlai, Z, Christensen, T., and S. Frolking. Focus on the impact of climate change on wetland ecosystems and carbon dynamics. Environmental Research Letters 11(10): 100201, 10.1088/1748-9326/11/10/100201, 2016.

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