Spring and Summer Peak Seasons For Phosphorus Deposition!
Ann Arbor, MI — Approximately 80% of the atmospheric phosphorus deposition observed in Lake Simcoe occurs during the spring and summer months.
A decline in Lake Simcoe water quality, attributed to the deposition of excessive nutrients (phosphorus), has been observed over the past few decades. It is estimated that 25-50% of the total phosphorus entering the lake is from atmospheric deposition.
"Lake Simcoe is the largest inland lake in Southern Ontario and is a major lifeline to a variety of industries and ecosystems," says Lee Weiss, a researcher at the University of Guelph. "Observing a seasonal phosphorus deposition cycle and understanding where the atmospheric deposition loads due to local sources are highest are major steps towards focusing management practices to reduce non-point pollution sources to the lake."
The noticeable cyclic change in phosphorus loading is lowest during the winter months, followed by a sharp increase in the late spring and early summer with a decline in loads during the autumn season. Additionally, bare soil exposure, due to lack of vegetative cover, along with soil disturbance result in higher susceptibility to wind erosion and dust emission. Spatially, phosphorus loads were higher in the northwest and southeast quadrants of the lake. Most of the soils with the highest vulnerability for wind erosion are located in these quadrants and the dominant winds blow in the NW-SE direction.
Original Publication Information
Results of this study, "Seasonal and Spatial Distribution patterns of Atmospheric Phosphorus Deposition to Lake Simcoe, ON," are reported by Laura Brown, Vahid Taleban, Bahram Gharabaghi and Lee Weiss in the latest issue (Volume 37, Suppl. 3, pp. 15-25) of the Journal of Great Lakes Research, published by Elsevier, 2011.
Contacts
For more information about the study, contact Bahram Gharabaghi, School of Engineering, University of Guelph, Guelph, ON N1L 2W1, bgharaba@uoguelph.ca, (519) 824-4120.
For information about the Journal of Great Lakes Research, contact Marlene Evans, Editor, National Water Research Institute, Environment Canada, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada; jglr@ec.gc.ca; (306) 975-5310.
Since 1967, IAGLR has served as the focal point for compiling and disseminating multidisciplinary knowledge on North America's Laurentian Great Lakes and other large lakes of the world and their watersheds. In part, IAGLR communicates this knowledge through publication of the Journal of Great Lakes Research, available to members in print and electronic form. A searchable archive of the journal is available online and includes the abstracts of articles from the journal's inception in 1975 through the most recent issue. In addition, complete articles are available to members who have signed up for an electronic subscription.