Deakin University
Browse
macreadie-netdrawdown-2022.pdf (6.87 MB)

Net Drawdown of Greenhouse Gases (CO2, CH4 and N2O) by a Temperate Australian Seagrass Meadow

Download (6.87 MB)
Version 2 2024-06-06, 10:50
Version 1 2022-03-30, 09:02
journal contribution
posted on 2024-06-06, 10:50 authored by QR Ollivier, DT Maher, C Pitfield, Peter Macreadie
AbstractSeagrasses have some of the highest rates of carbon burial on the planet and have therefore been highlighted as ecosystems for nature-based climate change mitigation. However, information is still needed on the net radiative forcing benefit of seagrasses inclusive of their associated greenhouse gas (GHG) emissions. Here, we report simultaneous estimates of seagrass-associated carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) air–water emissions. Applying in situ sampling within a south-east Australian seagrass ecosystem, this study finds atmospheric GHG emissions from waters above seagrasses to range from − 480 ± 15.96 to − 16.2 ± 8.32 mg CO2-equivalents m2 d−1 (net uptake), with large temporal and spatial variability. Using a combination of gas specific mass balance equations, dissolved stable carbon isotope values (δ13C) and in situ time-series data, CO2-e flux is estimated at − 21.74 mg m2 d−1. We find that the net release of CH4 (0.44 µmol m2 h−1) and net uptake of N2O (− 0.06 µmol m2 h−1) effectively negated each other at 16.12 and − 16.13 mg CO2-e m2 d−1, respectively. The results of this study indicate that temperate Australian seagrasses may function as net sinks of atmospheric CO2-e. These results contribute towards filling key emission accounting gaps both in the Australian region, and through the simultaneous measurement of the three key greenhouse gas species.

History

Journal

Estuaries and Coasts

Volume

45

Pagination

2026-2039

Open access

  • Yes

ISSN

1559-2723

eISSN

1559-2731

Language

en

Publication classification

C1 Refereed article in a scholarly journal

Issue

7

Publisher

Springer Science and Business Media LLC

Usage metrics

    Research Publications

    Categories

    No categories selected

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC