Production ecology in the Northern Baltic

Abstract

Production biology in the Bothnian Bay is discussed and compared to that of the southern parts of the Baltic. Severe ice-conditions, low water temperatures in spring and early summer and a pronounced water-colouring cause a delay of the spring development of phytoplankton and a low annual production in the Bothnian Bay. This delay makes possible a higher efficiency of the pelagic system as the zooplankton fauna can develop in harmony with the food resources. The downward transport of energy and matter to the bottom communities from an efficient pelagial should be small and temporally unpredictable, which is thought to be an adequate explanation of the observed very low benthic fauna biomasses in the Bothnian Bay.