Toggle Main Menu Toggle Search

Open Access padlockePrints

Carbon export from seaweed forests to deep ocean sinks

Lookup NU author(s): Professor Pip MooreORCiD

Downloads


Licence

This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).


Abstract

© The Author(s), under exclusive licence to Springer Nature Limited 2024. The coastal ocean represents an important global carbon sink and is a focus for interventions to mitigate climate change and meet the Paris Agreement targets while supporting biodiversity and other ecosystem functions. However, the fate of the flux of carbon exported from seaweed forests—the world’s largest coastal vegetated ecosystem—is a key unknown in marine carbon budgets. Here we provide national and global estimates for seaweed-derived particulate carbon export below 200 m depth, which totalled 3–4% of the ocean carbon sink capacity. We characterized export using models of seaweed forest extent, production and decomposition, as well as shelf–open ocean water exchange. On average, 15% of seaweed production is estimated to be exported across the continental shelf, which equates to 56 TgC yr−1 (range: 10–170 TgC yr−1). Using modelled sequestration timescales below 200 m depth, we estimated that each year, 4–44 Tg seaweed-derived carbon could be sequestered for 100 years. Determining the full extent of seaweed carbon sequestration remains challenging, but critical to guide efforts to conserve seaweed forests, which are in decline globally. Our estimate does not include shelf burial and dissolved and refractory carbon pathways; still it highlights a relevant potential contribution of seaweed to natural carbon sinks.


Publication metadata

Author(s): Filbee-Dexter K, Pessarrodona A, Pedersen MF, Wernberg T, Duarte CM, Assis J, Bekkby T, Burrows MT, Carlson DF, Gattuso J-P, Gundersen H, Hancke K, Krumhansl KA, Kuwae T, Middelburg JJ, Moore PJ, Queiros AM, Smale DA, Sousa-Pinto I, Suzuki N, Krause-Jensen D

Publication type: Article

Publication status: Published

Journal: Nature Geoscience

Year: 2024

Volume: 17

Pages: 552-559

Print publication date: 01/06/2024

Online publication date: 22/05/2024

Acceptance date: 05/04/2024

Date deposited: 20/06/2024

ISSN (print): 1752-0894

ISSN (electronic): 1752-0908

Publisher: Springer Nature

URL: https://doi.org/10.1038/s41561-024-01449-7

DOI: 10.1038/s41561-024-01449-7

ePrints DOI: 10.57711/ne0v-6h15

Data Access Statement: Data for national and ecoregion area estimates, percentage export, carbon export, NPP, decomposition and other parameters are available in Suppl Data 1. Additional information on uncertainties around parameters and assumptions are provided in Suppl Information. Predictive layers and model outputs of CRT, percentage export data and POC export are available at figshare (https://doi.org/10.6084/m9.figshare.24116973). Areal estimates for floating and sinking seaweed forest were modelled from species occurrence records and stacked distribution estimates that are openly available at figshare (https://doi.org/10.6084/m9.figshare.14496018.v4). Benthic currents and bathymetric data are available from Bio-ORACLE. Source data for net primary productivity models are openly available, and the dataset is described in Scientific Data (https://doi.org/10.1038/s41597-022-01554-5). Source CRTs are archived at NOAA GFDL (ftp://data1.gfdl.noaa.gov/users/Xiao.Liu/CRT_simulation/GFDL-MOM6-SIS2/).


Altmetrics

Altmetrics provided by Altmetric


Funding

Funder referenceFunder name
Australian Research Council (DE190100692, FT230100214, DP220100650, LP220200004)
Foundation for Science and Technology (UIDB/04326/2020, UIDP/04326/2020, LA/P/0101/2020)
Individual Call to Scientific Employment Stimulus (2022.00861.CEECIND/CP1729/CT0003)
Independent Research Fund Denmark (8021-00222 B, 'CARMA')
Norwegian Blue Forest Network and EUROMARINE (FWS_07-2018)

Share