A healthy hydrosphere with a rich biodiversity and functioning ecosystem ensures oxygen and food. Smaller benthic organisms are known to respond to fluctuation in sea-ice cover and benthic food regimes (Säring et al. 2022, Veit-Köhler et al. 2018) but particularly knowledge of their role for ecosystem services as carbon storage and cycling is still lacking. For example, meiofauna communities and ecosystem services have rarely been considered in the planning of Marine Protected Areas. The Southern Ocean is facing increasing pressure from climate change effects. International efforts such as the Southern Ocean Action Plan (UN Decade 2021–2030) aim to manage and protect this unique ecosystem. The Weddell Sea (WS) has been the focus of German Antarctic research for 40 years and an MPA initiative has been underway since 2013 (Teschke et al. 2021). The fairly good database and the established stakeholder network make the WS an excellent case study for integrating seabed knowledge (Jerosch et al. 2015) into conservation and management measures, relevant for other marine regions under the Antarctic Treaty System and future High Seas Treaty areas. We aim to 1. provide a detailed description of sediment-inhabiting meio- and macrofauna, 2. include modern approaches for accelerated and in-depth analyses, 3. quantify and map ecosystem functions and services, and 4. integrate the knowledge into MPA planning and conservation of shelf and slope habitats under different climate change stressors. Led by the University of Rostock, partners from four institutions (URO, AWI, SaM, HIFMB) will create this baseline knowledge from field experiments in the WS , integrate the findings, create spatial models and transfer the knowledge to stakeholders, including CCAMLR, the Biodiversity of the Blue Ocean Cluster and the public. BEnToolsMaPs will combine knowledge on the structure and function of Southern Ocean seafloor systems, facilitating decision-making on sustainable management of carbon storage and biodiversity ecosystem services. References Jerosch, K, Kuhn, G, Krajnik, I, Scharf, F, Dorschel, B (2015). A geomorphological seabed classification for the Weddell Sea, Antarctica. Mar Geophys Res 37, 127–141 (2016). https://doi.org/10.1007/s11001-015-9256-x Säring F, Veit-Köhler G, Seifert D, Liskow I, Link H (2022b). Sea-ice-related environmental drivers affect meiofauna and macrofauna communities differently at large scales (Southern Ocean, Antarctic). Marine Ecology Progress Series 700: 13-37, https://doi.org/10.3354/meps14188 Veit-Köhler G, Durst S, Schuckenbrock J, Hauquier F, Durán Suja L, Dorschel B, Vanreusel A, Martínez Arbizu P (2018) Oceanographic and topographic conditions structure benthic meiofauna communities in the Weddell Sea, Bransfield Strait and Drake Passage (Antarctic). Prog Oceanogr 162:240–256. https://doi.org/10.1016/j.pocean.2018.03.005 Teschke, K, Brtnik, P, Hain, S, Herata, H, Liebschner, A, Pehlke, H, Brey, T (2021). Planning marine protected areas under the CCAMLR regime – The case of the Weddell Sea (Antarctica). Mar. Policy 124. https://doi.org/10.1016/j.marpol.2020.104370