Shi Wenting, Zhai Weidong, Yang Shu, Guo Congcong, Liu Zichen, Chen Hongmei
Institute of Marine Science and Technology, Shandong University, Qingdao, 266237, China.
Frontiers Research Center, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519082, China.
Mar Environ Res. 2025 Oct;211:107392. doi: 10.1016/j.marenvres.2025.107392. Epub 2025 Jul 19.
The dissolution of marine carbonate minerals represents a scalable carbon dioxide (CO) removal approach toward global climate goals. In this study, potential buffering capacity of naturally distributed carbonate minerals against future rises in atmospheric CO and thereby coastal acidification were assessed using field data obtained in the Bohai Sea, Yellow Sea and Chinese major estuaries. Results showed that highly soluble carbonate minerals such as calcite and aragonite dominated surface sediments, constituting 8-12 % of dry weight of sediments in Chinese major estuaries, while lowly soluble carbonate minerals (mostly dolomite) accounted for <1.5 %. At a conservative estimate, the South Yellow Sea particulate inorganic carbon (PIC) pool west of 124 °E in the region can potentially convert 21 × 10 mol CO (equivalent to 0.9 Mt CO or 0.25 Tg C) into bicarbonate. If the atmospheric CO further rises in the future, the Yellow Sea represents one of the most vulnerable systems within the Chinese seas to adverse impacts from ocean acidification. Based on the projection of CaCO saturation states under the future atmospheric CO rise, Yellow Sea aragonite pools will dissolve sooner than calcite pools. However, the future projection suggests that the air-equilibrated Ω will not decline to 2.0-2.1 in the Yellow Sea by the 2050s, implying that the South Yellow Sea's calcite pool may not play an important role in buffering the atmospheric CO rise.
海洋碳酸盐矿物的溶解是一种可扩展的二氧化碳（CO₂）去除方法，有助于实现全球气候目标。在本研究中，利用在渤海、黄海和中国主要河口获得的实地数据，评估了自然分布的碳酸盐矿物对未来大气CO₂上升及由此导致的沿海酸化的潜在缓冲能力。结果表明，方解石和文石等高溶解性碳酸盐矿物主导着表层沉积物，在中国主要河口占沉积物干重的8 - 12%，而低溶解性碳酸盐矿物（主要是白云石）占比<1.5%。保守估计，该区域东经124°以西的南黄海颗粒无机碳（PIC）库有可能将21×10⁶摩尔CO₂（相当于0.9百万吨CO₂或0.25太克碳）转化为碳酸氢盐。如果未来大气CO₂进一步上升，黄海是中国海域中对海洋酸化不利影响最脆弱的系统之一。根据未来大气CO₂上升情况下碳酸钙饱和度状态的预测，黄海文石库将比方解石库更早溶解。然而，未来预测表明，到2050年代，黄海与空气平衡的Ω值不会降至2.0 - 2.1，这意味着南黄海的方解石库在缓冲大气CO₂上升方面可能不会发挥重要作用。
