Eutrophication

Nitrogen and phosphorus discharged from sewers and leaching from farmland cause severe environmental problems in water and forest areas. Eutrophying substances are also transported by winds and deposited with rain and snow.

• • Sea and forest affected by nitrogen deposition

    Today, precipitation contains considerably more nitrates and ammonia than it did before the Second World War. Road traffic and shipping are the main sources of nitrogen oxide emissions.

• • Fertiliser use in farming

    The use of fertilisers on farms increased sharply after the Second World War. The volumes of phosphorus and nitrogen discharged into lakes and coastal areas today therefore considerably exceed those at the beginning of the 20th century.

• • Seas, lakes and groundwater

    Since the early 20th century, eutrophication has been causing problems of overgrown bays and creeks, and the areas of water free from its effects have been shrinking.