Aquascope Facts

What is eutrofication?

Freshwater outflow
Compared to the rocks in the background of the picture above, a great many more one-year green algae grow on the rocks in the foreground. One reason for this is that more nutrients reach those stones that are closest to the stream in this part of the bay. There are no human pollutants in the stream, but it runs through a bank of seaweed. The black coating on the rocks is not oil, but black cyanobacteria. The rocks further up are bright and bare because they are situated in the unfriendly bare belt.
The supply of nutrients to the sea is a prerequisite for Marine life and is therefore not an environmental problem. A problem arises when variations in the supply of nutrients effect the character or function of the ecosystem negatively. By nutrients, we mean elements that organisms (i.e. alga) need to photosynthesise and develope normally. The most important of these nutrients are nitrogen and phosphorous that are normally taken up in the form of ions : nitrogen as nitrates, nitrites or ammonium; and phosphorous as phosphates.
    When we refer to eutrofication of the sea, we often mean environmental pollution, but eutrofication really means "to enrich with nutrients". An ecosystem can be eutrophic without being damaged or negatively effected, it can be nutritous and luxuriant. Commonly, eutrofication is wrongly thought to mean över-fertilization, that the system recieves too many nutrients and results in the occurrence of a great many fast growing algae and that certain micro-organisms thrive in greater numbers.
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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