MONTREAL, Aug. 16 (UPI) -- A Canadian ecologist says changing weather may be the reason for an increase in blue-green algae bloom in Quebec lakes.

David Bird of the University of Quebec in Montreal says heavy downpours, droughts and warm winters appear to be linked to problems with toxic cyanobacteria, The (Montreal) Gazette said Wednesday.

The newspaper said many of Quebec’s watersheds are polluted by phosphorus from agricultural and lawn fertilizer, leaking septic tanks and detergents containing phosphates.

Speaking to scientists at the 30th Congress of the International Association of Theoretical and Applied Limnology in Montreal, Bird said weather data from 2005 and 2006 at Missisquoi Bay of Lake Champlain suggests phosphorus levels are made worse by heavy downpours that erode pesticide-laden topsoil before the water pours into the lake.

He said drought-like conditions following the downpours would cause evaporation of water from the lake, which would lead to a higher concentration of phosphorus.

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