Acidification is caused by sulphur-rich soil coming in contact with oxygen, which then forms sulphur dioxide that leaks out in the oceans through streams and rivers. This is also caused naturally by the land uplift, but the effect is enhanced by agriculture and forestry when lands are drained. When the acidity level in the water sinks, it has negative effects on plants and animals, and increases even further if the acidification is combined with high levels of metals.

Picture 1: Acifidication caused by sulphur

Picture 2: Bottom affected by sulphur


Sedin, A (2002). Miljööversikt – Havets tillstånd i Kvarkenområdet. Kvarken miljö, Vasa.