Blue carbon storage in Fijian seagrass meadows: First insights into carbon, nitrogen and phosphorus content from a tropical southwest Pacific Island

Shalini Singh; Monal M Lal; Paul C Southgate; Morgan Wairiu; Awnesh Singh

doi:10.1016/j.marpolbul.2022.113432

Blue carbon storage in Fijian seagrass meadows: First insights into carbon, nitrogen and phosphorus content from a tropical southwest Pacific Island

Mar Pollut Bull. 2022 Mar:176:113432. doi: 10.1016/j.marpolbul.2022.113432. Epub 2022 Feb 24.

Authors

Shalini Singh¹, Monal M Lal², Paul C Southgate³, Morgan Wairiu⁴, Awnesh Singh⁴

Affiliations

¹ Pacific Centre for Environment and Sustainable Development, The University of the South Pacific, Lower Laucala Campus, Laucala Bay Road, Suva, Fiji; College of Agriculture, Fisheries and Forestry, Fiji National University, Koronivia, Nausori, Fiji. Electronic address: sophie.shalinisingh@gmail.com.
² Australian Centre for Pacific Islands Research and School of Science, Technology and Engineering, University of the Sunshine Coast, Maroochydore, Queensland 4558, Australia; Discipline of Marine Studies, School of Agriculture, Geography, Environment, Ocean and Natural Sciences, University of the South Pacific, Lower Laucala Campus, Laucala Bay Road, Suva, Fiji.
³ Australian Centre for Pacific Islands Research and School of Science, Technology and Engineering, University of the Sunshine Coast, Maroochydore, Queensland 4558, Australia.
⁴ Pacific Centre for Environment and Sustainable Development, The University of the South Pacific, Lower Laucala Campus, Laucala Bay Road, Suva, Fiji.

PMID: 35217418
DOI: 10.1016/j.marpolbul.2022.113432

Abstract

Seagrasses provide vital ecosystem services which include the accumulation and storage of carbon and nutrients in sediments and biomass. Despite their importance in climate change mitigation and adaptation, seagrass ecosystems have been poorly studied, particularly in the Pacific. Therefore, the present study assessed variability in sedimentary and vegetative C, N and P storage in three monospecific seagrass meadows (Halophila ovalis, Halodule pinifolia and Halodule uninervis), reporting baseline data for the first time. Sediment C_org stocks ranged from 31 to 47 Mg C ha^-1 and varied (p < 0.001) between seagrass meadows, unvegetated areas and locations. Comparison of N and P storage between vegetated meadows and unvegetated areas revealed differences (p < 0.05); implying seagrass meadows function as C, N and P sinks. Differences in species composition and environmental conditions, may play a key role in estimating C, N and P stocks, which are valuable data for conservation and monitoring of seagrass ecosystems.

Keywords: Biomass; Blue carbon; Fiji; Intertidal habitats; Seagrass; Sediment storage.

MeSH terms

Carbon Sequestration
Carbon* / analysis
Ecosystem*
Geologic Sediments
Nitrogen
Pacific Islands
Phosphorus

Substances

Phosphorus
Carbon
Nitrogen