Algae invade lakes and fuel the concern of residents

On the municipal beach of Lake Roxton. Similarly, in Estrie, the shallow waters of the shore are covered with a film of a suspect green. In addition, Cyanobacteria, which is also called blue-green algae, take advantage of hot and dry weather to multiply.

On this beautiful summer morning. Moreover, the bathers fall back on the swimming pool, located a few meters from the body of water. Therefore, Pagaie board enthusiasts put their boats in the water by going to the end of the pontoon. Similarly, a way of bypassing the problem.

We don’t bathe in therewarns the president of the environment committee of Lake Roxton. For example, Simon Turcotte, while ensuring that there is no risk if we remain at a good distance from the area occupied by algae.

Lake residents have used their constant presence in algae invade lakes fuel concern a localized manner, with higher intensity hatching sometimes during the summerspecifies Mr. Nevertheless, Turcotte.

This child in the country spent his childhood feet in Lake Roxton. Moreover, In the 1990s and early 2000, it happened a few times, but today it is more frequenthe deplores.

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It was algae invade lakes fuel concern not surprised to learn that blue-green algae take advantage of global warming to proliferate. Moreover, This is the main conclusion of a study (in English) published in late July in Nature (new window) and codirigated by McGill University and Laval University.

A dozen researchers have done analyzes in 80 lakes across Canada. Furthermore, Almost everywhere, algae progress. By taking sediment carrots. they have been able to reconstruct the history of water bodies since the end of the 19th century^e century.

Since the 1960s, the presence of algae has increased seven times faster than in the previous 75 years. An observation that applies to all lakes, whether it is an urbanized environment or in the more remote sectors.

This data adds complexity to the fight against cyanobacteria. because so far at Lake Roxton and elsewhere, the fight against blue-green algae has algae invade lakes fuel concern concentrated on the reduction in nutrient contributions from human activity. In particular on the reduction of phosphorus. which stimulates the concentration of algae and which comes mainly from agriculture, but also from homes. This strategy has given encouraging results in several contexts.

We work very hard to try to improve the protection systems. that is to say the branches. We also work with farmers to try to find ways to reduce phosphorus intake.

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All our members are concerned. they are not all affected, fortunatelysays the retired biologist Henri Fournier, vice-president of the Quebec Federation for the Defense of Lakes and Rivers. Its organization brings together a hundred associations and municipalities.

This is an extremely important concern. he says, because blue-green algae have a direct impact on the use of water bodies and on the health of the population.

Cyanobacteria can indeed cause vomiting, headache or irritation. They also represent a danger to the health of animals, including fish.

We always think of swimming. but there are as many people who draw their water directly from the lakes.

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Algae invade lakes fuel concern

The effects of global warming

The health of water bodies also concerns researcher Yannick Huot. from the University of Sherbrooke. We find him at Lac d’Argent. in Eastman, where he plunges a device that serves him to analyze the quality of the water. Since 2019, he has been carrying out a wide research in more than 600 lakes across Canada.

It is also one of the authors of the recent study which gives a new perspective on the. proliferation of algae.

There is a huge diversity. These algae all compete for the same nutrients. and it is often cyanobacteria that winhe lets go, punctuating his words with a bitter laugh.

The phosphorus is naturally present in the bottom of the water bodies and it diffuses under the effect of heat.

According to the hypothesis supported by Yannick Huot. his colleagues, the effect of warming is mostly felt because the algae invade lakes fuel concern ice melted earlier and returned later, which leaves more time to cyanobacteria to multiply.

According to Yannick Huot. scientific literature demonstrates that there will be more algae in the lakes and therefore really more cyanobacteria.

Canada has more than 900,000 lakes and their good health is essential for drinking water, irrigation water, fishing or boating.