Impact of Reservoir Construction on Ocean Sediment Carbon Storage
New research suggests that reservoir construction is reducing carbon storage in ocean sediments. The study analyzed sediment cores from the South Yellow Sea and East China Sea and found that carbon stocks declined between 1855 and 1950 due to flooding, increased post-1950 due to sediment transport, and reduced since 1990 due to lower sediment transport caused by reservoirs and dams built upstream. The global average carbon stocks in marine sediments were calculated to be 66.6 tons per hectare, while the South Yellow Sea saw a reduction of 32% to 45.2 tons per hectare. This interference in the carbon cycle highlights the need for considering the negative impact on carbon stocks when siting dams and reservoirs.