This task has been executed by Kasper Hancke, Gunhild Borgersen, Anders Ruus and Marc Anglès d’Auriac at NIVA. The Nordic Blue Carbon (“Blått-karbon”) project was co-funded by The Norwegian Network for Blue Forests (NBFN.no) to increase the initial sample size of three to five sediment cores, thus being able to investigate carbon burial in a depth gradient from 300 down to 500 m. A field campaign was carried out 16-17. October 2018 at Frohavet in Trøndelag – an area assumed to have high kelp deposition rates. The sediment cores have been sliced, dated and analysed for different parameters to estimate the decomposition rate of organic carbon. Parameters analysed are contents of total of organic carbon (TOC) and chlorophyll, as well as different methods to identify source of carbon, such as genetic markers (DNA), lipids and stable isotopes. A manuscript on the degradation rates and long-term storage of kelp organic matter in Norwegian sediments is planned and assumed to be submitted to a peer review scientific journal by the end of the year.