Summary
Salinity and oxygen measurements were taken near bottom at 41 stations. Hydrogen sulphide was detected at 10 of these. Western Gotland Basin: Oxygen conditions at the bottom were very bad. Levels below 2 ml/l were found deeper than 55 metres. Hydrogen sulphide was recorded from a depth of 80 meters in general, but locally already from 65 meters. Eastern Gotland Basin (western part): Oxygen concentrations at bottom were very low. Levels below 2 ml/l were found from 70 metres and deeper. The area around the Midsjö Banks: Oxygen conditions at the bottom were good. The lowest oxygen amount recorded was 2.4 ml/l, corresponding to a saturation of 30%, at a depth of 73 metres. Bornholm Basin (including Hanö Bight): Oxygen conditions at the bottom were good. The lowest oxygen amount recorded was 2.3 ml/l, corresponding to a saturation of 30%, at a depth of 55 metres in the north-eastern part of the area.