Aquascope Facts

How shallow bays are effected by eutrofication

Green bottom
The fast growing green alga creates a fluffy covering on the bottom and over the perennial and relatively slow growing alga.
Generally, with over-fertilization in shallow bay areas along the Swedish west coast, it is the perennial eel grass that lose while competing against the annual and fast growing algae. The annual algae are so called opportunists, meaning that they quickly colonize areas that are rich in resources.
    An increase in food resources favours macroscopic algae, that are thread-like, have a short life and are fast growing. These algae are epifytes (grow on or around a host) on the perennial algae, which run the risk of being eliminated when light sources are cut off (or partially) so photosynthesis is not as effective. Powerful waves can tear loose many of the finely threaded algae and throw them up onto the beach where they lie and rot. In protected bays that are over-fertilized, the finely threaded algae are able to exist without any host to anchor them. Instead they build large mats over the bottom or lumps that float around.
    Those algae that have increased in shallow bays because of over-fertilization come mainly from the following families: Cladophora, Enteromorpha, Ulva, Ulvaria, Ulothrix and Rhizoclonium.
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A splendid outing ?
Problems and expectations
”It was better before"
Seawater and soluble salts
The sea moves
Coastal waters are close to us
What is eutrofication?
Sources of over-fertilization
How the open masses of water are effected
How shallow bays are effected
What can we do?
Alga harvest

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Bo Johannesson | Martin Larsvik | Lars-Ove Loo | Helena Samuelsson