What does the presence of seaweed on the beach mean for the environment?

Algarve University asks beachgoers to report seaweeds

Algarve University asks beachgoers to report seaweeds

Here is a long-dreamed chance for holidaymakers to combine leisure with benefit and help out the environment

Scientists from the University of Algarve (UAlg), in the south of Portugal, have issued a call to beachgoers to record the state of algae accumulation on the country’s beaches and report it to them. For this purpose, the researchers have created a digital platform, called Algas na Praia (Seaweeds on the Beach), the same as the project.

If you find yourself wondering why the accumulation of seaweed on the beach is important, the answer is that it can point to imbalances in the marine ecosystem – both in the water and on the sand.

It has to do with protecting marine biodiversity

The call for help is returning for a new edition after it was already tried out last summer. Scientists have noticed the presence of invasive seaweed species coming from as far away as Australia and Japan.

The sight of too many algae on the beach can be a nuisance as it makes swimming harder and unpleasant and when the biomass can cause an unpleasant smell when it rots. However, the issues are more than just aesthetic.

Seaweed overgrowth is often (if not only) the result of an excess of nutrients from the discharge of urban effluents or from fertilization in agriculture. When algae grow excessively, they can harm biodiversity, fisheries and the beach's environmental quality.

This is where beachgoers can put on their scientist assistant’s hats and join in with reporting the state of their favourite beach. Users can go to the dedicated platform (available in Portuguese and in English), fill in the questionnaire and submit photos they have taken. And with that, suddenly, a day at the beach will not be all about idleness.

The scientists study the input to evaluate patterns in accumulation and get a clearer picture of the state of coastal biodiversity.

But how do algae from Australia or Japan get there anyway? The researchers from the University of Algarve explained that they can come attached to the hulls of ships, but also through the importation of oysters, for example.

However, not everything is bad news and these species can even be useful. The same university also counts on the Nutrisafe project, which is studying how some of these algae can be used to create food supplements or medicines to fight chronic inflammation.



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