How Much Worth is the Deep-Sea ? Insights from a Meta-Analysis

ContextThe deep sea, covering vast areas below the 200-meter depth mark, represents a critical and complex frontier for sustainable development, encapsulating both immense economic potential (Folkersen & al., 2018) and vital ecosystem services (Thurber & al., 2014). Within the framework of the blue economy - formalized at the 2012 United Nations Conference on Sustainable Development, this largely uncharted region challenges conventional views of resource utilization and ecological preservation. Once perceived as inaccessible, the deep sea currently emerges as an essential area for balancing economic growth with environmental responsibility (Mejjad & Rovere, 2021). Despite increasing awareness of the need for sustainable management, the valuation of deep-sea resources often remains fragmented, particularly regarding non-market ecosystem services but also the incorporation of emerging sectors such as deep-sea mining (Sharma, 2017), ocean-based renewable energy or even marine biotechnology (Saide et al., 2021). This fragmented approach hinders the development of coherent policy frameworks and international cooperation, impeding a comprehensive understanding of the deep sea's true economic and ecological value. A robust monetary evaluation is essential to quantify these contributions effectively.The proposed contribution focuses on the results of a meta-analysis processed in the context of a collective scientific assessment on deep sea knowledge and governance issues, commissioned by the French government.Methodology and AnalysisThus, this paper aims to conduct a comprehensive meta-analysis to consolidate and synthesize existing research, grounded by the article of Folkersen et al. (2018), extending their work by addressing methodological gaps and proposing a unified framework for deep-sea resource valuation. This extended framework will not only refine the methodological approach but also provide an updated monetary valuation of deep-sea resources. We will employ a Systematic Literature Review (SLR) approach, utilizing the PRISMA protocol (Moher et al. 2009) for selecting relevant research articles. The SLR methodology provides a structured, replicable approach to identify literature on deep-sea resource valuation. By following it, we ensure an original approach not yet explored to this extent in the literature. The methodology will facilitate a deeper examination of how various valuation approaches have treated both market and non-market contributions, revealing inconsistencies and omissions in the current literature. By aggregating diverse findings and cross-comparing methodologies, this analysis should provide a holistic view that accounts for the regulatory, ecological and socio-economic dimensions critical for sustainable deep-sea resource management.For the One Ocean Science CongressOur research aligns with the One Ocean Science Congress 2025 theme 4. By conducting a meta-analysis that bridges fragmented valuation approaches and proposes a comprehensive framework, this work directly addresses the multifaceted value of the deep-sea. This is vital for shaping policies that seek a more resilient and inclusive model that prioritizes long-term ecological health over short-term exploitation (Spalding, 2016). This integrated approach reinforces the notion of the ocean as a common heritage of mankind (Bourrel et al., 2018) - emphasizing not just its direct profitability potential but also its role in supporting biodiversity (Paulus, 2021), climate regulation (Hilmi & al., 2023) and socio-cultural significance (Bennett et al., 2022; Barianaki et al., 2024).