16 Oct 2023
 | 16 Oct 2023
Status: this preprint is currently under review for the journal ESSD.

Predictive mapping of organic carbon stocks and accumulation rates in surficial sediments of the Canadian continental margin

Graham Epstein, Susanna D. Fuller, Dipti Hingmire, Paul G. Myers, Angelica Peña, Clark Pennelly, and Julia K. Baum

Abstract. The quantification and mapping of surficial seabed sediment organic carbon has wide-scale relevance across marine ecology, geology and environmental resource management, with carbon densities and accumulation rates being a major indicator of geological history, ecological function, and ecosystem service provisioning, including the potential to contribute to nature-based climate change mitigation. While global mapping products can appear to provide a definitive understanding of the spatial distribution of sediment carbon, there is inherently high uncertainty when making estimates at this scale. Finer resolution national maps which utilise targeted data syntheses and refined spatial data products are therefore vital to improve these estimates. Here, we report a national systematic review of data on organic carbon content in seabed sediments across Canada and combine this with a synthesis and unification of best available data on sediment composition, seafloor morphology, hydrology, chemistry, geographic setting and sediment mass accumulation rates within a machine learning mapping framework. Predictive quantitative maps of mud content, sediment dry bulk density, and organic carbon content, density and accumulation, were each produced along with cell specific estimates of their 95 % confidence interval (CI) bounds at 200 m resolution across 4,489,235 km2 of the Canadian continental margin (92.6 % of the seafloor area above 2,500 m). Fine-scale variation in carbon stocks was identified across the Canadian continental margin, particularly in the Pacific and Atlantic Ocean regions. Carbon accumulation was predicted to be concentrated in coastal areas, with the highest rates in the Gulf of St Lawrence and Bay of Fundy. Overall, we estimate the standing stock of organic carbon in the top 30 cm of surficial seabed sediments across the Canadian shelf and slope to be 10.7 Gt (95 % CI 6.6 – 16.0 Gt), and accumulation at 4.9 Mt per year (95 % CI 2.6 – 9.3 Mt y-1). Increased in-situ sediment data collection and higher precision in spatial environmental data-layers could significantly reduce uncertainty and increase accuracy in these products over time.

Graham Epstein et al.

Status: open (extended)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse

Graham Epstein et al.

Data sets

Predictive maps and related data on organic carbon stocks and accumulation rates in surficial sediments of the Canadian continental margin G. Epstein, S. D. Fuller, D. Hingmire, P. Myers, A. Peña, C. Pennelly, and J. K. Baum

Graham Epstein et al.


Total article views: 267 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
203 59 5 267 10 4 2
  • HTML: 203
  • PDF: 59
  • XML: 5
  • Total: 267
  • Supplement: 10
  • BibTeX: 4
  • EndNote: 2
Views and downloads (calculated since 16 Oct 2023)
Cumulative views and downloads (calculated since 16 Oct 2023)

Viewed (geographical distribution)

Total article views: 280 (including HTML, PDF, and XML) Thereof 280 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
Latest update: 01 Dec 2023
Short summary
Improved mapping of surficial seabed sediment organic carbon is vital for best practice marine management. Here, using systematic data reviews, data unification process and machine learning techniques, the first national predictive maps were produced for Canada at a 200-meter resolution. We show fine-scale spatial variation of organic carbon across the continental margin and estimate total standing stock in the top 30 cm of sediment to be 10.7 Gt and surficial accumulation at 4.9 Mt per year.