High rates of organic carbon burial in fjord sediments globally

The deposition and long-term burial of organic carbon in marine sediments has played a key role in controlling atmospheric oxygen and carbon dioxide concentrations over the past 500 million years. Marine carbon burial represents the dominant natural mechanism of long-term organic carbon sequestration. Fjords - deep, glacially carved estuaries at high latitudes - have been hypothesized to be hotspots of organic carbon burial, because they receive high rates of organic material fluxes from the watershed. Researchers compiled organic carbon concentrations from 573 fjord surface sediment samples and 124 sediment cores from nearly all fjord systems globally. The team used sediment organic carbon content and sediment delivery rates to calculate rates of organic carbon burial in fjord systems across the globe. Full abstract here.