In 1907 Weber referred to the vegetation of German peat bogs as 'eutraphent' if it needed high concentrations of essential elements. Naumann (1919) applied the term eutrophic, with the meaning of 'good nourishment', to Swedish lakes with a rich algal content. Limnologists subsequently developed a paradigm in which oligotrophic lakes become eutrophic as a result of increased nutrient loading, and came to see this development as undesirable. From about 1970 onwards the paradigm began to be applied to the sea. It was incorporated in international law, for example in the European 'Urban Waste Water Treatment' Directive (1990), and clarified for example by decisions by the European Court of Justice (2004, 2009). The European 'Marine Strategy Framework' Directive (2008) requires that “human-induced eutrophication is minimised, especially adverse effects thereof, such as losses in biodiversity, ecosystem degradation, harmful algae blooms and oxygen deficiency in bottom waters.” We build on earlier definitions, and on advances in scientific understanding, to propose that “Eutrophication is a process driven by enrichment of water by nutrients, especially compounds of nitrogen and/or phosphorus, leading to: increased growth, primary production and biomass of algae; changes in the balance of organisms; and water quality degradation. The consequences of eutrophication are undesirable if they appreciably degrade ecosystem health and/or the sustainable provision of goods and services.” We'll explore how this definition applies to the Baltic, Mediterranean, and North, Seas, and discuss it in relation to definitions based on organic enrichment

Third International Symposium on Research and Management of Eutrophication In Coastal Ecosystems. EUTRO 2010 15–18 June 2010 Nyborg, Denmark

Peer Reviewed