Aquascope Facts

Nutrients in the atmosphere

Big car
Modern cars have lower petrol consumption and emissions than the one pictured above.
The air we breath contains about 80% nitrogen. Plants usually cannot absorb nitrogen directly from the atmosphere, but take it up in the form of ions. Therefore nitrogen in gas form does not directly result in over-fertilization. The blue-green cyanobacterias are an exception as they are able to absorb the nitrogen in the atmosphere and therefore contribute to over -fertilization. This contribution can in the Baltic, comprise a large proportion of the total delivery. The blue-green bacteria have the ability to bind nitrogen gas from the atmosphere or decaying compounds into a nitrate.
    Air pollution is another factor because it also supplies the sea with nutrients. This load is known as atmospheric deposition.
    There are mainly two ways for nitrogen compounds to enter the atmosphere: as ammoniak and as nitrogen oxides from manure and artificial fertilizer entering the air and through combustion. Automobile combustion and incineration in power plants enables the oxygen and nitrogen in the atmosphere to combine and form compounds of nitrogen oxide.
These nitrogen oxides are deposited on the land, in rivers and lakes and directly into the sea, partly as dry deposits and partly as rain.
Coal powerplant
Automobile traffic is responsible for about half of the nitrogen oxides that pollute the atmosphere, the remaining comes from the use of fossil fuels in, for example, power plants. Those power plants that use coal are responsible for the greater part.
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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