About the Authors
Water Science and Technology Directorate, Environment Canada, Burlington, Ontario, Canada
Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, Ontario, Canada
The authors have declared that no competing interests exist.
Conceived and designed the experiments: JS SLS. Performed the experiments: JS SLS. Analyzed the data: JS SLS. Contributed reagents/materials/analysis tools: JS SLS SJB. Wrote the paper: JS SLS.