International Reference Group on Great Lakes Pollution from Land Use Activities International Joint Commission

iDISCLAIMER The study discussed in this document was carried out as part of the efforts of the International Reference Group on Great Lakes Pollution From Land Use Activities (PLUARG), an organization of the International Joint Commission (IJC), established under the Canada- U.S. Great Lakes Water Quality agreement of 1972. Funding for this study was provided through Agriculture Canada. Findings and conclusions are those of the authors and do not necessarily reflect the views of the Reference Group or its recommendations to the Commission. ii ACKNOWLEDGEMENTS There have been a large number of individuals who have contributed to this study. In particular, appreciation is extended to the following: Mr. Jack Vlasblom, field technician, IJC Watersheds No. 1 and 13 (located at Research Station, Harrow) for plot sampling, field records, and extraction of soil NH4- and NO3-N; Messrs. Ian Nicholsen, Keith Wires and Clarence O'Meara (Soil Research Institute, Ottawa) for excellent and efficient chemical analysis; Mrs. Valerie Malmsten, Mr. Don McDill and Mrs. Ilona Bain for computer programming and coding of simulation models; Dr. Chi Chang (Hydrology Research Division, Calgary) for managing the initial phases of this project; and the farmers (Mr. Ia