Life Sciences Commons^™

Substantial Blue Carbon Sequestration In The World’S Largest Seagrass Meadow, Chuancheng Fu, Sofia Frappi, Michelle N. Havlik, Wells Howe, S. David Harris, Elisa Laiolo, Austin J. Gallagher, Pere Masqué, Carlos M. Duarte

Research outputs 2022 to 2026

Seagrass meadows are important sinks for organic carbon and provide co-benefits. However, data on the organic carbon stock in seagrass sediments are scarce for many regions, particularly The Bahamas, which accounts for up to 40.7% of the documented global seagrass area, limiting formulation of blue carbon strategies. Here, we sampled 10 seagrass meadows across an extensive island chain in The Bahamas. We estimate that Bahamas seagrass meadows store 0.42–0.59 Pg organic carbon in the top-meter sediments with an accumulation rate of 2.1–2.9 Tg annually, representing a substantial global blue carbon hotspot. Autochthonous organic carbon in sediments decreased from ~1980 onwards, …

Inorganic Carbon Outwelling From A Mediterranean Seagrass Meadow Using Radium Isotopes, Claudia Majtényi-Hill, Gloria Reithmaier, Yvonne Y. Y. Yau, Oscar Serrano, Nerea Piñeiro-Juncal, Isaac R. Santos

Research outputs 2022 to 2026

Seagrass meadows are ‘blue carbon’ ecosystems widely recognised for their potential role in climate change mitigation. Previous studies have focused mainly on carbon storage within meadows and sediments. However, little is known about contribution of outwelling (i.e., lateral transport) to seagrass carbon budgets. Here, radium isotopes (²²³Ra and ²²⁴Ra) were used to assess dissolved inorganic carbon (DIC) and total alkalinity (TA) outwelling from a Mediterranean Posidonia oceanica meadow during early autumn. DIC outwelling was 114 ± 61 mmol m ^{− 2} day ^{− 1} and exceeded above-meadow CO2 outgassing (3 ± 1 mmol m ^{− 2} day …

Ranking The Risk Of Co2 Emissions From Seagrass Soil Carbon Stocks Under Global Change Threats, Martin Dahl, Kathryn Mcmahon, Paul S. Lavery, Serena H. Hamilton, Catherine E. Lovelock, Oscar Serrano

Research outputs 2022 to 2026

Seagrass meadows are natural carbon storage hotspots at risk from global change threats, and their loss can result in the remineralization of soil carbon stocks and CO2 emissions fueling climate change. Here we used expert elicitation and empirical evidence to assess the risk of CO2 emissions from seagrass soils caused by multiple human-induced, biological and climate change threats. Judgments from 41 experts were synthesized into a seagrass CO2 emission risk score based on vulnerability factors (i.e., spatial scale, frequency, magnitude, resistance and recovery) to seagrass soil organic carbon stocks. Experts perceived that climate change threats (e.g., gradual ocean warming and …

Review Of The Physical And Chemical Properties Of Seagrass Soils, Nerea Piñeiro-Juncal, Oscar Serrano, Miguel Ángel Mateo, Elena Diaz-Almela, Carmen Leiva-Dueñas, Antonio Martinez-Cortizas

Research outputs 2022 to 2026

Seagrasses are a polyphyletic group of angiosperms that colonized marine environments more than 30 million years ago and currently inhabit coastal soft and rocky substrates in all continents except Antarctica. Due to their evolution from terrestrial plants, seagrasses have belowground organs that interact with the substrate, transforming it through chemo-physical processes analogous to terrestrial soil formation. Although seagrass substrates provide valuable ecosystem services including carbon and coastal stabilization, they have been largely regarded as sediments by marine scientists and neglected in soil science research. However, over the last decades, the increasing interest in carbon accumulation by seagrasses has generated multiple …

Species Traits And Geomorphic Setting As Drivers Of Global Soil Carbon Stocks In Seagrass Meadows, H. Kennedy, J. F. Pagès, D. Lagomasino, A. Arias-Ortiz, P. Colarusso, J. W. Fourqurean, M. N. Githaiga, J. L. Howard, D. Krause-Jensen, T. Kuwae, Paul S. Lavery, P. I. Macreadie, N. Marbà, Pere Masqué, I. Mazarrasa, T. Miyajima, Oscar Serrano, C. M. Duarte

Research outputs 2022 to 2026

Our knowledge of the factors that can influence the stock of organic carbon (OC) that is stored in the soil of seagrass meadows is evolving, and several causal effects have been used to explain the variation of stocks observed at local to national scales. To gain a global-scale appreciation of the drivers that cause variation in soil OC stocks, we compiled data on published species-specific traits and OC stocks from monospecific and mixed meadows at multiple geomorphological settings. Species identity was recognized as an influential driver of soil OC stocks, despite their large intraspecific variation. The most important seagrass species …

Impacts Of Land-Use Change And Urban Development On Carbon Sequestration In Tropical Seagrass Meadow Sediments, Martin Dahl, Rashid Ismail, Sara Braun, Pere Masqué, Paul S. Lavery, Martin Gullström, Ariane Arias-Ortiz, Maria E. Asplund, Andrius Garbaras, Liberatus D. Lyimo, Matern S.P. Mtolera, Oscar Serrano, Chanelle Webster, Mats Björk

Research outputs 2022 to 2026

Seagrass meadows store significant carbon stocks at a global scale, but land-use change and other anthropogenic activities can alter the natural process of organic carbon (Corg) accumulation. Here, we assessed the carbon accumulation history of two seagrass meadows in Zanzibar (Tanzania) that have experienced different degrees of disturbance. The meadow at Stone Town has been highly exposed to urban development during the 20th century, while the Mbweni meadow is located in an area with relatively low impacts but historical clearing of adjacent mangroves. The results showed that the two sites had similar sedimentary Corg accumulation rates (22–25 g m−2 yr−1) …

Heterogeneous Tidal Marsh Soil Organic Carbon Accumulation Among And Within Temperate Estuaries In Australia, Connor Gorham, Paul S. Lavery, Jeffrey J. Kelleway, Pere Masque, Oscar Serrano

Research outputs 2014 to 2021

The scarcity of data on tidal marsh soil accumulation rates (SAR) and soil organic carbon accumulation rates (CAR) globally precludes a comprehensive assessment of the role of tidal marshes in climate change mitigation and adaptation. Particularly few data exist from the southern hemisphere and for Australia in particular, which contains ~24% of globally recognised tidal marsh extent. Here we estimate SAR and CAR over the last 70 years using 210Pb-based geochronologies in temperate estuarine tidal marsh ecosystems in southern Western Australia (WA). Specifically, we assessed tidal marsh ecosystems situated in two geomorphic settings (marine vs. fluvial deltas) within 10 wave-dominated, …

Challenges To Select Suitable Habitats And Demonstrate ‘Additionality’ In Blue Carbon Projects: A Seagrass Case Study, Anna Lafratta, Oscar Serrano, Pere Masqué, Miguel A. Mateo, Milena Fernandes, Sam Gaylard, Paul S. Lavery

Research outputs 2014 to 2021

© 2020 Elsevier Ltd Seagrass restoration has been suggested as a Blue Carbon (BC) strategy for climate change mitigation. For Nationally Determined Contributions (NDC) and carbon crediting schemes, BC projects need to demonstrate ‘additionality’, that is enhanced CO2 sequestration and/or avoided greenhouse gas emissions following management actions. This typically requires determining soil carbon accumulation rates (CAR), which is often done using radionuclides or surface elevation tables to estimate sedimentation rates. Here we undertook a case study, using 210Pb and 14C dating, to detect possible changes in Corg stocks and CAR following the loss and partial recovery of Posidonia seagrass meadows …

Organic Chemistry Insights For The Exceptional Soil Carbon Storage Of The Seagrass Posidonia Australis, Oscar Serrano, Mohammad Rozaimi, Paul Lavery, Ronald J. Smernik

Research outputs 2014 to 2021

The high organic carbon (OC) stores in seagrass meadows have led to their recognition as significant Blue Carbon sinks, though the diagenetic conditions that enable OC retention in seagrass soils remain poorly understood. In this study, seagrass soils were sampled from a Posidonia australis meadow in Oyster Harbour (Albany; south-western Australia) to investigate the preservation of sedimentary OC. We analysed soil characteristics (colour, grain size and redox potential), radiocarbon age, and characterised the soil organic matter (OM) using solid state CP/MAS 13C NMR spectroscopy to examine the preservation of OM down the soil profile. There was minimal change in organic …

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

Research Datasets

This database contains data on top 30 cm soil biogeochemical properties from soil cores (minimum length of 30 cm) sampled in seagrass (n=201 cores) and adjacent unvegetated patches (n=39) around Australia.

Average biogeochemical properties per core along with information about type of environment, biotic characteristics and environmental conditions.

In particular, the variables included in sheet 1 are:

- Core ID (column A): core code

- Location (column B): name of the region of the sampling site.

- Latitude / Longitude (columns C, D): latitude and longitude

- Bioregion (column E): classified the sampling sites according to …

Fingerprinting Blue Carbon: Rationale And Tools To Determine The Source Of Organic Carbon In Marine Depositional Environments, Nathan R. Geraldi, Alejandra Ortega, Oscar Serrano, Peter I. Macreadie, Catherine E. Lovelock, Dorte Krause-Jensen, Hilary Kennedy, Paul S. Lavery, Michael L. Pace, Joeri Kaal, Carlos M. Duarte

Research outputs 2014 to 2021

Blue carbon is the organic carbon in oceanic and coastal ecosystems that is captured on centennial to millennial timescales. Maintaining and increasing blue carbon is an integral component of strategies to mitigate global warming. Marine vegetated ecosystems (especially seagrass meadows, mangrove forests, and tidal marshes) are blue carbon hotspots and their degradation and loss worldwide have reduced organic carbon stocks and increased CO₂ emissions. Carbon markets, and conservation and restoration schemes aimed at enhancing blue carbon sequestration and avoiding greenhouse gas emissions, will be aided by knowing the provenance and fate of blue carbon. We review and critique current …

Modeling Organic Carbon Accumulation Rates And Residence Times In Coastal Vegetated Ecosystems, E. Fay Belshe, Jose Sanjuan, Carmen Leiva-Dueñas, Nerea Piñeiro-Juncal, Oscar Serrano, Paul Lavery, Miguel Angel Mateo

Research outputs 2014 to 2021

Coastal vegetated “blue carbon” ecosystems can store large quantities of organic carbon (OC) within their soils; however, the importance of these sinks for climate change mitigation depends on the OC accumulation rate (CAR) and residence time. Here we evaluate how two modeling approaches, a Bayesian age-depth model alone or in combination with a two-pool OC model, aid in our understanding of the time lines of OC within seagrass soils. Fitting these models to data from Posidonia oceanica soil cores, we show that age-depth models provided reasonable CAR estimates but resulted in a 22% higher estimation of OC burial rates when …

Organic Carbon Sequestration And Storage In Vegetated Coastal Habitats Along The Western Coast Of The Arabian Gulf, M Cusack, V Saderne, A Arias-Ortiz, Pere Masque, P K. Krishnakumar, L Rabaoui, M A. Qusem, P Prihartato, R A. Loughland, A A. Elyas, C M. Duarte

Research outputs 2014 to 2021

Certain coastal ecosystems such as mangrove, saltmarsh and seagrass habitats have been identified as significant natural carbon sinks, through the sequestration and storage of carbon in their biomass and sediments, collectively known as 'blue carbon' ecosystems. These ecosystems can often thrive in extreme environments where terrestrial systems otherwise survive at the limit of their existence, such as in arid and desert regions of the globe. To further our understanding of the capability of blue carbon ecosystems to sequester and store carbon in such extreme climates, we measured carbon sediment stocks in 25 sites along the Western Arabian Gulf coast. While …

Habitat Characteristics Provide Insights Of Carbon Storage In Seagrass Meadows, Inés Mazarrasa, Jimena Samper-Villarreal, Oscar Serrano, Paul S. Lavery, Catherine E. Lovelock, Núrià N. Marbà, Carlos M. Duarte, Jorge A. Cortés

Research outputs 2014 to 2021

Seagrass meadows provide multiple ecosystem services, yet they are among the most threatened ecosystems on earth. Because of their role as carbon sinks, protection and restoration of seagrass meadows contribute to climate change mitigation. Blue Carbon strategies aim to enhance CO2 sequestration and avoid greenhouse gasses emissions through the management of coastal vegetated ecosystems, including seagrass meadows. The implementation of Blue Carbon strategies requires a good understanding of the habitat characteristics that influence Corg sequestration. Here, we review the existing knowledge on Blue Carbon research in seagrass meadows to identify the key habitat characteristics that influence Corg sequestration in seagrass …

Effects Of Small-Scale, Shading-Induced Seagrass Loss On Blue Carbon Storage: Implications For Management Of Degraded Seagrass Ecosystems [Dataset], Stacey M. Trevathan-Tackett, Caitlin Wessel, Just Cebrian, Peter J. Ralph, Pere Masque´, Peter I. Macreadie

Research Datasets

1. Seagrass meadows are important global ‘blue carbon’ sinks. Despite a 30% loss of seagrasses globally during the last century, there is limited empirical research investigating the effects of disturbance and loss of seagrass on blue carbon stocks.

2. In this study, we hypothesised that seagrass loss would reduce blue carbon stocks. Using shading cloth, we simulated small-scale die-offs of two subtropical seagrass species, Halodule wrightii and Thalassia testudinum, in a dynamic northern Gulf of Mexico lagoon. The change in quantity and quality of sediment organic matter and organic carbon were compared among kill, control and bare plots before the …

Sequestration Of Macroalgal Carbon: The Elephant In The Blue Carbon Room, Dorte Krause-Jensen, Paul Lavery, Oscar Serrano, Nu´Ria Marba, Pere Masque´, Carlos M. Duarte

Research outputs 2014 to 2021

Macroalgae form the most extensive and productive benthic marine vegetated habitats globally but their inclusion in Blue Carbon (BC) strategies remains controversial. We review the arguments offered to reject or include macroalgae in the BC framework, and identify the challenges that have precluded macroalgae from being incorporated so far. Evidence that macroalgae support significant carbon burial is compelling. The carbon they supply to sediment stocks in angiosperm BC habitats is already included in current assessments, so that macroalgae are de facto recognized as important donors of BC. The key challenges are (i) documenting macroalgal carbon sequestered beyond BC habitat, (ii) …

Commentary: Evaluating The Role Of Seagrass In Cenozoic Co2 Variations, Peter I. Macreadie, Óscar Serrano, Carlos M. Duarte, John Beardall, Damien T. Maher

Research outputs 2014 to 2021

A commentary on Evaluating the Role of Seagrass in Cenozoic CO₂ Variations

by Brandano, M., Cuffaro, M., Gaglianone, G., Pettricca, P., Stagno, V., and Mateu-Vicens, G. (2016). Front. Environ. Sci. 4:72. doi:10.3389/fenvs.2016.00072

Brandano et al. (2016) sought to quantify the role of seagrasses in removing atmospheric CO₂ during the past 65 million years. To date, this estimate has been missing from the literature. Moreover, as the authors point out, there has so far been little attention paid to the role of calcium carbonate formation (CaCO₃; inorganic carbon precipitated by calcifying organisms) in seagrass carbon budgets; much …

Carbon Sequestration By Australian Tidal Marshes, Peter I. Macreadie, Q. R. Oliver, J. J. Kelleway, Oscar Serrano, P. E. Carnell, C. J. Ewers Lewis, T. B. Atwood, J. Sanderman, J. Baldock, R. M. Connolly, C. M. Duarte, Paul Lavery, A. Steven, C. E, Lovelock

Research outputs 2014 to 2021

Australia’s tidal marshes have suffered significant losses but their recently recognised importance in CO2 sequestration is creating opportunities for their protection and restoration. We compiled all available data on soil organic carbon (OC) storage in Australia’s tidal marshes (323 cores). OC stocks in the surface 1 m averaged 165.41 (SE 6.96) Mg OC ha − 1 (range 14 – 963 Mg OC ha − 1). The mean OC accumulation rate was 0.55 ± 0.02 Mg OC ha − 1 yr − 1. Geomorphology was the most important predictor of OC stocks, with fluvial sites having twice the stock of OC …

A Marine Heat Wave Drives Massive Losses From The World’S Largest Seagrass Carbon Stocks [Dataset], Ariane Arias-Ortiz, Oscar Serrano, Pere Masqué, Paul Lavery, Ute A. Mueller, Gary A, Kendrick, Mohammad Rozaimi, Alba Esteban, James W, Fourqurean, Núrià N. Marbà, Miquel-Angel Mateo, Kathy Murray, Michael Rule, Carlos M. Duarte

Research Datasets

The database compiles published data (in Arias-Ortiz et al., 2018) on biogeochemical characteristics (density, organic carbon, stable carbon isotopes and sediment grain size) of soils underneath seagrass meadows in Shark Bay, Western Australia. Pb-210 concentrations of the first 20 cm are included along with C-14 raw ages. The dataset compiles data for a total of 49 cores, 25 - 300 cm-long (11 cores with Pb-210 and C-14 data). Enquiries about the dataset may be sent to Ariane Arias-Ortiz: ariane.arias@uab.cat