Human activities are threatening the quality and quantity of Canada's freshwater resources and more protection is needed in key regions, according to ecologists at the University of Toronto.

Activities that are changing the country's landscape range from resource development of Alberta's tar sands and potential development in the Ring of Fire in northern Ontario, to declines in timber harvest and the number of operational farms. But researchers argue that many aquatic resources remain unprotected.

"The conservation and management of aquatic ecosystems in Canada needs to keep pace with the country's changing landscape," said Cindy Chu, a former postdoctoral researcher at the University of Toronto and lead author of a study published in the Canadian Journal of Fisheries and Aquatic Sciences.

The research team examined environmental, human census and business pattern data from across Canada. Their analysis suggested that climate warming and northward expansion of human activities over a 10-year period from 1996 to 2006 posed a threat to water resources, especially in areas with the most human activity.

"By combining the data we were able to identify regions that need attention," explained Chu, an aquatic research biologist with the Ontario Ministry of Natural Resources and Forestry. "Attention has typically been given to watersheds in British Columbia, southern Ontario, southern Quebec and the Maritimes. Our research shows that Canada's changing landscape means that attention is needed elsewhere, too."

According to the study, watersheds along the southern border of Canada and in northern regions of some provinces should be prioritized for conservation through more intensive monitoring, research or management.