KVÄVE OCH FOSFOR SOM BIOMASSABEGRÄNSANDE ÄMNEN I HAVET / Nitrogen and Phosphorus as Growth Limiting Substances in the Sea
The controversy whether nitrogen or phosphorus limits phytoplankton growth in Swedish coastal and sea areas has been ongoing since the early 1970’s. Today there is a consensus among scientists that nitrogen is the key factor controlling phytoplankton growth in the Baltic proper, Kattegat and Skagerrak and phosphorus in the Bothnian Bay, while the Bothnian Sea seems to be a transition area. The debate has however continued in newspapers and popular magazines, delaying proper management actions. A major reason to the confusion is a biased use of published information. A survey of the literature shows that nitrogen and in some instances phosphorus may limit the growth of phytoplankton in marine coastal areas, and thus both opinions can find support. The reasons may be external (nutrient load) as well as internal (e.g. water residence time) differences which must be considered when data are used in generalisations. “Complete abstract not presented.”