The roles of organic matter in seawater have often been discussed from the aspect of metal toxicity and bioavailability in seawater. In fact, organic ligands, as part of the organic matter, can work as a trace metal ion buffer system. At the same time, however, the release of well-defined metal chelators as exudates by, for example, marine bacteria is necessary to compete with natural metal com...

Dissolved Natural Organic Matter (DNOM) is a heterogeneous mixture of partly degraded, oxidised and resynthesised organic compounds terrestrial or aquatic origin. In the boreal biome, it plays central role in element cycling practically all biogeochemical processes governing physico-chemistry surface waters. Because multiple processes, especially microbial respiration, an improved understanding...