image: (a) Total organic carbon(OC), (b)C/N, (c) δ13C, (d) relative portion of terrestrial OC, (e) relative portion of marine OC, (f) Δ14C, (g) age of the OC, and (h) Black carbon (BC) in the Bohai Sea, Yellow Sea and East China Sea
Credit: ©Science China Press
This study is led by Dr Shi Xuefa, Dr. Wu Bin, and Dr. Qiao Shuqing from the First Institute of Oceanography, Ministry of Natural Resources, China. The researchers have finely depicted the distribution and controlling factors of sedimentary organic carbon and precisely calculated the burial flux of organic carbon based on sediment budget balance in the eastern China seas. They proposed that organic carbon is mainly buried in seven key mud areas and identified a significant carbon sink effect in these study regions.
The distribution of sedimentary organic carbon in the Bohai Sea, Yellow Sea, and East China Sea is closely associated with the distribution of fine-grained sediment components. This has resulted in a pattern where organic carbon is relatively concentrated in mud areas, while it is generally lower in non-mud regions, such as the eastern and northeastern Bohai Sea, the central and eastern Yellow Sea, the northern Jiangsu shallow waters, and the mid-shelf of the East China Sea. Based on sediment budget balance calculations, the mud areas are identified as the main burial regions for organic carbon in these seas. The organic carbon burial fluxes in the mud areas are 8.20 Mt C a⁻¹, accounting for about 5.3% of the global seabed burial flux. Of this, the burial flux of biospheric organic carbon is 6.92 Mt C a⁻¹. Under natural conditions, the amount of organic carbon fixed annually in the sediments of China’s eastern coastal waters is equivalent to 25.37 Mt of atmospheric CO2, highlighting a significant carbon sink effect.
The study provides a detailed overview of the distribution and burial patterns of sedimentary organic carbon in the Bohai Sea, Yellow Sea, and East China Sea. It precisely calculates the organic carbon burial flux and estimates the magnitude of the carbon sink effect, effectively uncovering the "baseline" of organic carbon in these regions.
See the article:
Shi X, Wu B, Qiao S, Yao Z, Hu L, Bai Y, Hu S, Sheng J, Liu Y, Liu S, Wang K, Zou J. 2024. Distribution, burial fluxes and carbon sink effect of sedimentary organic carbon in the eastern China seas. Science China Earth Sciences, 67(10): 3062–3082, https://doi.org/10.1007/s11430-024-1412-0
Journal
Science China Earth Sciences