Aquascope Facts
Most of the nutrients in the area known as the Västerhav (Kattegat, Skagerrak and Öresund) are brought in from the Atlantic in the north, from the south via the English Channel, and by currents from Baltic via the Öresund and the Great Belt. Thus, the majority of nutrients in the Västerhav do not originate from Sweden, but coastal areas are effected locally by the run-off from Swedish rivers and basins. This is also true of the Baltic, where countries to the east and south are the largest contributors of nutrients to the Baltic.
Distribution of nutrients
Those nutrients that contribute most to over-fertilization of the seas around Sweden are believed to be nitrogen and phosphorous. The principal sources of nutrient input are from agriculture, sewage and atmospheric fallout.

Nutrients from agriculture

The majority of nutrients that effect the sea come from agriculture. With intensive animal farming, manure is a waste product that is thought to be problem and often needs to be disposed of at the lowest cost. Manure contains amongst other things, nitrogen in the form of nitrates and ammonia. Most of the manure is spread out on the fields as a liquid-like fertilizer, but unfortunately the liquid-like consistency has a tendency to clog, rather than improve the soil, which does not happen with normal manuring. This liquid-like manure can even be flushed out of the earth and end up in the ground water, rivers and streams and take the nutrients with it. Finally, these nutrients end up in the sea.
Previous page Page 11 of 28 Next page
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

Home    Contents    Inspiration    Facts    Collaboration  

© Aquascope 2000   Tjärnö Marine Biological Laboratory, Strömstad, Sweden
Bo Johannesson | Martin Larsvik | Lars-Ove Loo | Helena Samuelsson