| Autor: |
Barnes DKA; British Antarctic Survey, NERC, Madingley Road, Cambridge CB3 0ET, UK., Bell JB; School of Geography, University of Leeds, Leeds LS2 9JT, UK., Bridges AE; School of Biological and Marine Sciences, University of Plymouth, Plymouth PL4 8AA, UK., Ireland L; British Antarctic Survey, NERC, Madingley Road, Cambridge CB3 0ET, UK., Howell KL; School of Biological and Marine Sciences, University of Plymouth, Plymouth PL4 8AA, UK., Martin SM; Tristan da Cunha Conservation Department, Edinburgh TDCU 1ZZ, UK., Sands CJ; British Antarctic Survey, NERC, Madingley Road, Cambridge CB3 0ET, UK., Mora Soto A; School of Geography and the Environment, University of Oxford, Oxford OX1 3QY, UK., Souster T; Faculty of Biosciences, Fisheries and Economics, Norges Arktisk Universitet, veg18, 9019 Tromso, Norway., Flint G; British Antarctic Survey, NERC, Madingley Road, Cambridge CB3 0ET, UK., Morley SA; British Antarctic Survey, NERC, Madingley Road, Cambridge CB3 0ET, UK. |
| Abstrakt: |
Carbon-rich habitats can provide powerful climate mitigation if meaningful protection is put in place. We attempted to quantify this around the Tristan da Cunha archipelago Marine Protected Area. Its shallows (<1000 m depth) are varied and productive. The 5.4 km 2 of kelp stores ~60 tonnes of carbon (tC) and may export ~240 tC into surrounding depths. In deep-waters we analysed seabed data collected from three research cruises, including seabed mapping, camera imagery, seabed oceanography and benthic samples from mini-Agassiz trawl. Rich biological assemblages on seamounts significantly differed to the islands and carbon storage had complex drivers. We estimate ~2.3 million tC are stored in benthic biodiversity of waters <1000 m, which includes >0.22 million tC that can be sequestered (the proportion of the carbon captured that is expected to become buried in sediment or locked away in skeletal tissue for at least 100 years). Much of this carbon is captured by cold-water coral reefs as a mixture of inorganic (largely calcium carbonate) and organic compounds. As part of its 2020 Marine Protection Strategy, these deep-water reef systems are now protected by a full bottom-trawling ban throughout Tristan da Cunha and representative no take areas on its seamounts. This small United Kingdom Overseas Territory's reef systems represent approximately 0.8 Mt CO 2 equivalent sequestered carbon; valued at >£24 Million GBP (at the UN shadow price of carbon). Annual productivity of this protected standing stock generates an estimated £3 million worth of sequestered carbon a year, making it an unrecognized and potentially major component of the economy of small island nations like Tristan da Cunha. Conservation of near intact habitats are expected to provide strong climate and biodiversity returns, which are exemplified by this MPA. |
