Assessment of blue carbon stocks and seagrass health dynamics in the Gulf of Tunis: case study of the Sidi Rais barrier reef

Assessment of blue carbon stocks and seagrass health dynamics in the Gulf of Tunis: case study of the Sidi Rais barrier reef | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Assessment of blue carbon stocks and seagrass health dynamics in the Gulf of Tunis: case study of the Sidi Rais barrier reef Asma JLassi, Walid Oueslati, Sami khemiri, Haifa Ben Mna, Valérie Mesnage, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8730053/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 4 You are reading this latest preprint version Abstract Climate change is a major global environmental challenge, and marine vegetation, or blue carbon habitats, are crucial in mitigating it by storing large amounts of atmospheric CO 2 . These ecosystems are highly effective at carbon sequestration. This study is among the first in Tunisia to assess the carbon storage capacity of seagrass meadows. By quantifying the total organic carbon (TOC) in three cores collected approximately 100 m offshore from the beach at the Posidonia oceanica barrier reef, with water depths ranging from 0.5 to 2.0 m, and using remote sensing to map the seagrass beds, we determined both short and long-term carbon sequestration. Results highlight the considerable carbon sequestration potential of seagrass ecosystems. The short-term carbon storage capacity, estimated at 137.6 gC m − 2 yr − 1 , whereas the long-term sequestration flux reached 32 gC m − 2 yr − 1 . These results underline the importance of seagrass beds in both short-term carbon uptake and long-term storage on the Tunisian coast. It has also been found that the Sidi Rais seagrass bed, an important marine ecosystem, stores annually around 15,864 tonnes of CO 2 , compensating for 6.8% of annual local CO 2 emissions, estimated at 233,486 tonnes per year for 849,184 inhabitants in 2019. Despite their role in carbon sequestration, seagrass cover has alarmingly declined from 133 hectares (2009) to 97 (2015) and, more recently, 51 hectares in 2021, according to mapping results. This work aligns with the growing evidence of the contribution of seagrass to climate change while highlighting the need to preserve it on the Tunisian coast. blue carbon seagrass beds remote sensing sediments climate change Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 15 Feb, 2026 Editor assigned by journal 11 Feb, 2026 Submission checks completed at journal 11 Feb, 2026 First submitted to journal 29 Jan, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8730053","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":591748968,"identity":"9de19db8-855e-4f6d-b941-9e0709381ffa","order_by":0,"name":"Asma 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These ecosystems are highly effective at carbon sequestration. This study is among the first in Tunisia to assess the carbon storage capacity of seagrass meadows. By quantifying the total organic carbon (TOC) in three cores collected approximately 100 m offshore from the beach at the \u003cem\u003ePosidonia oceanica\u003c/em\u003e barrier reef, with water depths ranging from 0.5 to 2.0 m, and using remote sensing to map the seagrass beds, we determined both short and long-term carbon sequestration. Results highlight the considerable carbon sequestration potential of seagrass ecosystems. The short-term carbon storage capacity, estimated at 137.6 gC m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e yr\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, whereas the long-term sequestration flux reached 32 gC m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e yr\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. 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