Ocean conservation boosts climate change mitigation and adaptation

Marine protected areas (MPAs) are increasingly being promoted as an ocean-based climate solution. However, such claims remain controversial because of the diffuse and poorly synthesized literature on benefits MPAs. To address this knowledge gap, we conducted a systematic review 22,403 publications spanning 241 MPAs analyzed these across 16 ecological social pathways through which could contribute to change mitigation adaptation. Our meta-analysis demonstrates that marine conservation can significantly enhance carbon sequestration, coastal protection, biodiversity, reproductive capacity organisms well fishers’ catch income. Most only achieved in fully or highly increase with MPA age. Although alone cannot offset all impacts, they useful tool for adaptation social-ecological systems. IntroductionClimate has started undermine human well-being planetary health, generating sense urgency identify effective strategies.1IPCCClimate Change 2022: Impacts, Adaptation, Vulnerability. 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Additional when allowed quantify aspects studied yet captured S2; Figure S4). definition units indicator detailed Table S2. protection), included comparing exploited preserved officially labeled done effect preservation initiatives, comparable MPAs, abundant, whereas almost available.The generated total publications, 378 counting, providing insights Publications unevenly distributed continents (Figures 1B–1D), Europe Asia S2). except buffering, plasticity Eight had (n > 3) meta-analysis.Marine sequestrationWe (C) six C sinks: three (mangrove, tidal marshes, seagrass), already (IPCC) accounting schemes,36Groupe d’experts intergouvernemental sur l’évolution du climat2013 Supplement 2006 IPCC Guidelines National Greenhouse Gas Inventories: Wetlands: Methodological Guidance Lands Wet Drained Soils, Constructed Wetlands Wastewater Treatment. 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Black dots indicate overlap zero white those zero. Sample studies) n values. ?In meta-analyses, representing individual studies.(D–F) Effect habitat type (D), level (E), presence area (F) benefits. Colors, sample size, same meaning †Effects (fish only) Lester al.16Lester ‡Effects Zupan al.15Zupan ScholarView Large Image ViewerDownload Hi-res image