Sammanfattning
Mapping of winter nutrient conditions in the Baltic Proper was performed. The nutrients showed typical winter concentrations in all areas. A tendency for a beginning spring bloom was observed in the Kattegat, while there were no signs of biological activity in the other basins. Hydrogen sulphide was detected in the Hanö Bight, the Bay of Gdansk and in the eastern, northern and western Gotland Basins. Oxygen concentrations below 2 ml/l was found at depths greater than 70 metres in the whole Baltic Proper. The oxygen conditions in the deep water are now, with the exception of the Bornholm Basin, the worst since the beginning of the 80ths.