Abstract
AbstractThe role of continental margin sediments in the carbon cycle and the associated management potential for climate mitigation are currently poorly understood. Previous work has indicated that margin sediments store significant amounts of organic carbon, but few studies have quantified the rates at which organic carbon is accumulated. Here, we use machine learning to make spatial predictions of the organic carbon stocks and accumulation rates of sediments on the Norwegian continental margin. We show that surface sediments (upper 10 cm) store 814 Tg and accumulate 6 Tg yr−1 of organic carbon. Shelf-incised glacial troughs account for 39% of the stocks and 48% of the accumulation, with the main accumulation hotspot located in the Skagerrak. Continental margin sediments accumulate organic carbon at scales much larger than vegetated coastal ecosystems in Norway because of their larger extent. Future studies should explore to what extent management interventions could increase accumulation rates, e.g., by minimising anthropogenic disturbance of seafloor sediments.
Publisher
Springer Science and Business Media LLC
Reference97 articles.
1. Keil, R. Anthropogenic Forcing of Carbonate and Organic Carbon Preservation in Marine Sediments. Ann. Rev. Mar. Sci. 9, 151–172 (2017).
2. Berner, R. A. The long-term carbon cycle, fossil fuels and atmospheric composition. Nature 426, 323 (2003).
3. Gershanovich, D. E., Gorshkova, T.I. & Koniukhov, A.I. Organic matter in recent sediments of continental margins. in Organic matter in recent and fossil sediments and methods of its investigation (Nauka, Moscow, 1974).
4. Berner, R. A. Burial of organic carbon and pyrite sulfur in the modern ocean: Its geochemical and environmental significance. Am. J. Sci. 282, 451–473 (1982).
5. Hedges, J. I. & Keil, R. G. Sedimentary organic matter preservation: an assessment and speculative synthesis. Mar. Chem. 49, 81–115 (1995).