Aquascope Facts

How the open masses of water are effected

Alga bloom
In the blooming pictured above, the density of dinoflagellates have coloured the water dark red.

Problems from over-fertilizing can occur when production and consumption are no longer in equalibrium; if there is a surplus of nutrients, then production will increase to such an extent that existing organisms are unable to consume this over-production. Plant plankton is responsible for the majority of the Marine production. Normally two blooms (sizable occurrences), occur yearly, during the spring and autumn.
During the spring bloom, diatoms dominate, while during the autumn, dinoflagellates dominate in the water. Alga blooms can occur when there are many nutrients in the water, at the same time as there are a great many organisms that eat plant plankton. This enables plant plankton to grow quickly with the minimum of disturbance. This production occurs mainly in the surface areas that are exposed to the sunlight. Animal plankton, for example copepods, are the largest consumers of plant plankton.
    A well known example of an unusual alga bloom was during the spring of 1988. The microscopic alga Chrysochromulina polylepis bloomed along the Swedish west coast at a time of relatvely low salt content, high water temperatures and abundant supplies of nitrogen. The effects were catastrophic when many organisms died or were weakened by the poison the alga produced.
Dead fish
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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