Recovery of Acidified Lakes: Lessons From Sudbury, Ontario, Canada
Over 7,000 lakes around Sudbury, Ontario, Canada were acidified by S deposition associated with emissions from the Sudbury metal smelters and more distant S sources. Air pollution controls have led to widespread changes in damaged Sudbury lakes, including increased pH and decreased concentrations of SO4, metals and base cations. While chemical improvements have often been substantial, many lakes are still acidified, although water quality recovery is continuing. Biological recovery has been observed in some lakes among various groups of organisms including fish, zooplankton, phytoplankton and zoobenthos. Generally, however, biological recovery is still at an early stage. Lakes around Sudbury are also showing that the recovery of acid-damaged lakes is closely linked to the effects of other major environmental stressors such as climate change, base cation depletion and UV-B irradiance. Future studies of the recovery of acid-damaged lakes around Sudbury, and in other regions, will need to consider the interactions of these and other stressors.
Keywordsacidification lakes recovery Sudbury sulphur stressors interaction
- Arnott, S. E., Yan, N., Keller, W., & Nicholls, K. (2001). The influence of drought-induced acidification on the recovery of plankton in Swan Lake (Canada). Ecological Applications, 11, 747–763.Google Scholar
- Keller, W., Pitblado, J. R., & Carbone, J. (1992). Chemical responses of acidic lakes in the Sudbury, Ontario, area to reduced smelter emissions, 1981–1989. Canadian Journal of Fisheries and Aquatic Sciences, 49(Suppl. 1), 25–32.Google Scholar
- Neary, B. P., Dillon, P. J., Munro, J. R., & Clark, B. J. (1990). The acidification of Ontario lakes: An assessment of their sensitivity and current status with respect to biological damage (Tech. Rep., p. 171). Dorset, Ontario, Canada: Ontario Ministry of Environment.Google Scholar
- Vander Zanden, J., Wilson, K. A., Casselman, J. M., & Yan, N. D. (2004). Species introductions and their impacts in North American Shield lakes, Chapter 13. In J. M. Gunn, R. J. Steedman, & R. A. Ryder (Eds.), Boreal shield watersheds – lake trout ecosystems in a changing environment. Boca Raton: CRC.Google Scholar
- Watson, G., Hunt, C., & Keller, W. (1999). Natural and enhanced aquatic ecosystem development at Inco’s former Garson 10.2 open pit mine, p. 419–428. In D. Goldsack, N. Belzile, P. Yearwood, & G. Hall (Eds.), Proceedings mining and the environment II. Sudbury, Ontario.Google Scholar