10.18453/rosdok_id00001948 Hammer, Karoline Karoline Hammer http://d-nb.info/gnd/1138037257 Universität Rostock 2017 550 Earth sciences 540 Chemistry & allied sciences 2017 en http://purl.uni-rostock.de/rosdok/id00001948 urn:nbn:de:gbv:28-diss2017-0112-3 The Baltic Sea is characterized by low inorganic alkalinities and high concentrations of dissolved organic matter (DOM). The contribution of DOM to the marine acid-base system has mostly been ignored in previous studies based on the assumption that coastal waters exhibit the same conditions as oceanic waters. The present thesis investigated concentrations and acid-base properties of total DOM, humic/fulvic acids and carboxylic acids. Conducted field, laboratory and theoretical studies revealed a not negligible contribution of organic compounds to the alkalinity in the Baltic Sea.