Aquascope Facts
Over-fertilized bay seen from above
These favoured algae recieve an abundance of nutrients and light. Between 30% and 50% of the total shallow bottom area along the coast of Bohuslän can be covered by these one year green algae. Most algae is found in the bays of northern Bohuslän.
    The shallow bays are an important link between the sea and the land, for example as a feeding area for certain birds that even spend part of their life on land. They are even important as feeding and breeding areas for commercially important populations of cod and varying specie of flatfish, i.e. plaice.
    Variations in vegetation and its composition are of great importance for the presence of fish and bottom-living creatures, but because of increasing over-fertilization and the resulting increase in the distribution of the finely threaded algae, composition of the specie within this ecosystem has changed. It has been shown that the flatfish population has decreased, because a third of their breeding areas are no longer suitable and this has mainly effected young plaice. It is believed that even the coastal cod population has been effected in the same way because their feeding areas have decreased in numbers.
    It is not just over-fertilization that has caused the death of bottom-living organisms. There are certain bottom-living organisms that can take advantage of the increase in nutrients, as long as there is a supply of oxygen. Such specie that can increase in numbers under such circumstances are eel and the shore crab.
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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