Factors determining seagrass blue carbon across bioregions and geomorphologies

Authors

Ines Mazarrasa, Edith Cowan UniversityFollow
Paul Lavery, Edith Cowan UniversityFollow
Carlos M. Duarte
Anna Lafratta, Edith Cowan UniversityFollow
Catherine E. Lovelock
Peter I. Macreadie
Jimena Samper-Villarreal
Cristian Salinas, Edith Cowan UniversityFollow
Christian J. Sanders
Stacey Trevathan-Tackett
Mary Young
Andy Steven
Oscar Serrano, Edith Cowan UniversityFollow

Author Identifier

Paul Lavery

https://orcid.org/0000-0001-5162-273X

Anna Lafratta

https://orcid.org/0000-0001-8414-2417

Cristian Salinas

https://orcid.org/0000-0002-4716-5991

Oscar Serrano

https://orcid.org/0000-0002-5973-0046

Document Type

Journal Article

Publication Title

Global Biogeochemical Cycles

Publisher

Wiley

School

School of Science / Centre for Marine Ecosystems Research

RAS ID

36651

Funders

Australian Research Council

Funding details : https://doi.org/10.1029/2021GB006935

Grant Number

ARC Number : 170101524

Grant Link

http://purl.org/au-research/grants/arc/DE170101524

Comments

Mazarrasa, I., Lavery, P., Duarte, C. M., Lafratta, A., Lovelock, C. E., Macreadie, P. I., ... & Serrano, O. (2021). Factors determining seagrass Blue Carbon across bioregions and geomorphologies. Global Biogeochemical Cycles, 35 (6), e2021GB006935. https://doi.org/10.1029/2021GB006935

Abstract

Seagrass meadows rank among the most significant organic carbon (C_org) sinks on earth. We examined the variability in seagrass soil C_org stocks and composition across Australia and identified the main drivers of variability, applying a spatially hierarchical approach that incorporates bioregions and geomorphic settings. Top 30 cm soil C_org stocks were similar across bioregions and geomorphic settings (min-max: 20–26 Mg C_org ha⁻¹), but meadows formed by large species (i.e., Amphibolis spp. and Posidonia spp.) showed higher stocks (24–29 Mg C_org ha⁻¹) than those formed by smaller species (e.g., Halodule, Halophila, Ruppia, Zostera, Cymodocea, and Syringodium; 12–21 Mg C_org ha⁻¹). In temperate coastal meadows dominated by large species, soil C_org stocks mainly derived from seagrass C_org (72 ± 2%), while allochthonous C_org dominated soil C_org stocks in meadows formed by small species in temperate and tropical estuarine meadows (64 ± 5%). In temperate coastal meadows, soil C_org stocks were enhanced by low hydrodynamic exposure associated with high mud and seagrass C_org contents. In temperate estuarine meadows, soil C_org stocks were enhanced by high contributions of seagrass C_org, low to moderate solar radiation, and low human pressure. In tropical estuarine meadows formed by small species, large soil C_org stocks were mainly associated with low hydrodynamic energy, low rainfall, and high solar radiation. These results showcase that bioregion and geomorphic setting are not necessarily good predictors of soil C_org stocks and that site-specific estimates based on local environmental factors are needed for Blue Carbon projects and greenhouse gases accounting purposes.

DOI

10.1029/2021GB006935

Related Publications

Salinas Zapata, C. C. (2022). Seagrass soils as paleoenvironmental tools and biogeochemical sinks for management. https://ro.ecu.edu.au/theses/2542

Related Datasets

Mazarrasa, I., Lavery, P., Duarte, C. M., Lafratta, A., Lovelock, C. E., Macreadie, P. I., Samper-Villarreal, J., Salinas, C., Sanders, C., Trevathan-Tackett, S., Young, M., Steven, A., & Serrano, O. (2020). Top 30 cm soil C org stocks, isotopic C org signature (13dC) and fine sediment content (silt and clay %) estimated in soil cores sampled in seagrass meadows around Australia [dataset]. Edith Cowan University. http://dx.doi.org/10.25958/gps9-m874

Creative Commons License

This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License