Contact John Spoelstra:

Phone & Address


Adjunct Assistant Professor, Department of Earth and Environmental Sciences, University of Waterloo

Associate Faculty, Faculty of Graduate Studies, Wilfrid Laurier University


Ph.D. Earth Sciences, University of Waterloo, 2004

Hon. B.Sc. University of Waterloo, 1996


John Spoelstra

Research Scientist - Groundwater Quality and Assessment Section

CURRENT S&T / RESEARCH - Contributing to Environment Canada’s mandate to ensure aquatic ecosystems are conserved and protected

  • Sources and fate of nitrogen-based contaminants in groundwater and surface water
  • Impacts of land management on water quality in forested and agricultural watersheds
  • Development and application of stable isotope tools for biogeochemistry research
  • Groundwater quality issues of the Great Lakes Basin


Thesis co-supervisor for three M.Sc. students and one undergraduate student

Thesis committee member for three Ph.D. and two M.Sc. students


Spoelstra, J., S.L. Schiff, R.G. Semkin, D.S. Jeffries, and R.J. Elgood. 2010. Nitrate attenuation in a small temperate wetland following forest harvest. Forest Ecology and Management 259: 2333-2341.

Snider, D.M., Schiff, S.L., Spoelstra, J. 2009. 15N/14N and 18O/16O stable isotope ratios of nitrous oxide produced during denitrification in temperate forest soils. Geochimica et Cosmochimica Acta 73: 877-888.

Spoelstra, J., S.L. Schiff, P.W. Hazlett, D.S. Jeffries and R.G. Semkin. 2007. The isotopic composition of nitrate produced from nitrification in a hardwood forest floor. Geochimica et Cosmochimica Acta. 71: 3757-3771.

Foster, N.W., J. Spoelstra, P.W. Hazlett, S.L. Schiff, F.D. Beall, I.F. Creed and C.A. David. 2005. Heterogeneity in soil nitrogen within first-order forested catchments at the Turkey Lakes Watershed. Canadian Journal of Forest Research. 35: 797-805.

Schiff, S.L., J. Spoelstra, R.G. Semkin and D.S. Jeffries. 2005. Drought induced pulses of SO42- from a Canadian Shield wetland: Use of δ34S and δ18O in SO42- to determine sources of S. Applied Geochemistry. 20: 691-700.

Spoelstra, J., S.L. Schiff, D.S. Jeffries and R.G. Semkin. 2004. Effect of storage on the isotopic composition of nitrate in bulk precipitation. Environmental Science & Technology. 38: 4723-4727.

Schiff, S.L., K.J. Devito, R.J. Elgood, P.M. McCrindle, J. Spoelstra, and P. Dillon. 2002. Two adjacent catchments: Dramatically different nitrate export. Water Resources Research. 38(12):1292. doi:1029/2000WR000170.

Spoelstra, J., S.L. Schiff, R. Elgood, R.G. Semkin, and D.S. Jeffries. 2001. Tracing the sources of exported nitrate in the Turkey Lakes Watershed using 15N/14N and 18O/16O isotopic ratios. Ecosystems. 4:536-544.

Expertise Categories associated with this S&T Expert:

Nature & Wildlife
     Ecosystems & Habitats
          Agricultural impacts
     Great Lakes
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