Indications of change in the marine flora of the North Sea in the 1990s

This paper gives an up-date of the scientific knowledge of changes that occ urred in the flora of the North Sea since the Quality Status Report of the North Sea was published in 1994, and the Debris Assessment (Europe's Enviro nment) was published in 1995. It shows that, as an epicontinental semi-encl osed marine ecosystem, the North Sea conditions create complex interactions between the flora and the marine environment. Plankton distribution and su ccession are considered in the light of recent research, with a focus on ec osystem modelling. Changes in macrophyte biodiversity are reviewed in conne ction with pollution, Symptoms of eutrophication are believed to be respons es to increases in primary production, Community changes in plankton, seawe eds, and eelgrass also influence loser and higher levels in the food web. T he possible effects of predicted climate changes on the flora of the North Sea are investigated. The review demonstrates that, in the future, potentia l changes could affect the flora in relation to changes in solar radiation and temperature. Finally, attention is paid to crucial needs in related res earch, education, and conservation of species and habitats. (C) 1999 Elsevi er Science Ltd. All rights reserved.