The global ocean plays a vital role in trapping and storing carbon dioxide that would otherwise stay in the atmosphere and contribute to global warming. This report looks at the extent to which Scotland’s coastal and marine environment can play a part in this invaluable ecosystem service.
Many marine species capture and store ‘blue carbon’. In our seas, such species range from phytoplankton – microscopic plants found at the surface – to kelp beds, mussel beds and cold-water coral reefs. This study estimates the blue carbon resources of the Nature Conservation Marine Protected Areas and Special Areas of Conservation in Scotland’s inshore waters.
Blue carbon habitats in the inshore Marine Protected Area (MPA) network are estimated to produce at least 248,000 tonnes of organic carbon and 30,000t of inorganic carbon per year. Sediment stores in inshore MPAs accumulate 126,000t of organic carbon and 348,000t of inorganic carbon per year.
Stocks of carbon within the habitats and surface sediments of inshore MPAs are estimated at 9.4 million tonnes (Mt) organic carbon and 47.8 Mt inorganic carbon.
MPAs provide valuable protection to many marine habitats and species. Considering the carbon value of such habitats when making marine management decisions could help to better protect these habitats. In turn, this could further enhance their capacity to provide a carbon sink.
This study builds on an earlier assessment of carbon budgets and potential blue carbon stores in our coastal and marine environment. See: SNH Commissioned Report 761.
For updated figures on carbon stored within Scottish marine sediments, please refer to: Smeaton, C., Austin, W. and Turrell, W.R. 2020. Re-Evaluating Scotland's Sedimentary Carbon Stocks. Scottish Marine and Freshwater Science Vol 11 No 2, 16pp.