Illustration of green algae washed up on the Breton coast.
Here in September 2020 in Lorient, in Morbihan.
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C. Allain / 20 Minutes
At the end of May, one could think the problem of green algae disappeared in Brittany.
With historically low strandings, the region had hopes of seeing its nitrate reduction efforts pay off.
It wasn't.
Scattered by winter storms, the ulva have made a resounding return to the heart of a still very hot summer.
While autumn has taken up residence, the Center for Studies and Valorization of Algae (CEVA) nonetheless draws up a mixed assessment of the phenomenon which has been rotting the Breton coast for years.
After aerial overflights carried out from September 16 to 18, CEVA delivered its conclusions: the areas covered by green algae washed up in the bays would be 6% lower than the multi-year average.
The reason ?
The late arrival of ulva on our coasts which visibly limited the strandings.
Less accessible places
It is above all the drop in the quantity collected that is of concern.
According to the CEVA, the quantities are down 40% on average in Brittany compared to the average of the last ten years.
Should this be seen as a neglect on the part of communities?
Rather a weather phenomenon which has caused significant strandings in the mudflats and small creeks where machines cannot venture.
In addition, the drop in collected volumes shows significant local disparities.
With 8,000 tonnes of algae, Finistère shows a 30% drop in its volumes.
The Côtes d'Armor are doing even better with 8,700 tonnes collected, a drop of 60% compared to the average.
Miscellaneous
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Planet
Brittany: “It smells like a rotten egg”… Green algae are coming in force from the south
Water
Agriculture
Sea
Green algae
Pollution
Reindeer
Planet