10.18453/rosdok_id00004905 Waern, Malin Maria Malin Maria Waern http://d-nb.info/gnd/1375096923 https://orcid.org/0000-0002-2459-040X Universität Rostock 2025 500 Natural sciences 540 Chemistry & allied sciences 660 Chemical engineering 2025 en https://purl.uni-rostock.de/rosdok/id00004905 urn:nbn:de:gbv:28-rosdok_id00004905-5 The OPUS UV sensor (TriOS GmbH, Germany) was used to determine the total sulfide (total H2S) concentration in the Baltic Sea. Derived total H2S concentrations had a -2.0% relative error to control and LOD at 2.71 ± 1.09 µM when adjusted using the control values as reference. Control LOD was 2.36 ± 1.52 µM. Analyzing a transect from the Arkona Basin to the Eastern Gotland Basin over five months in 2021 showed recurring plume phenomenon within the oxic/sub-oxic zone, as well as a co-occurrence of total H2S and oxygen. These sulfides may reduce or completely halt some nitrification rates.