文献类型： 外文期刊

作者： Xiong, Tianqi ¹ ; Li, Hongmei ¹ ; Hu, Yubin ⁶ ; Zhai, Wei-dong ⁶ ; Zhang, Zhe ⁶ ; Liu, Yi ⁷ ; Zhang, Jihong ⁷ ; Lu, Longfei ⁸ ; Chang, Lirong ⁸ ; Xue, Liang ⁹ ; Wei, Qinsheng ⁹ ; Jiao, Nianzhi ⁴ ; Zhang, Yongyu ¹ ;

作者机构： 1.Chinese Acad Sci, Qingdao Inst Bioenergy & Bioproc Technol, CAS Key Lab Biofuels, Shandong Prov Key Lab Energy Genet, Qingdao 266101, Peoples R China

2.Qingdao Univ, Coll Environm Sci & Engn, Qingdao 266071, Peoples R China

3.Shandong Energy Inst, Qingdao 266101, Peoples R China

4.Xiamen Univ, State Key Lab Marine Environm Sci, Xiamen 361100, Peoples R China

5.Qingdao New Energy Shandong Lab, Qingdao 266101, Peoples R China

6.Shandong Univ, Inst Marine Sci & Technol, Qingdao 266237, Peoples R China

7.Chinese Acad Fishery Sci, Yellow Sea Fisheries Res Inst, Qingdao 266071, Peoples R China

8.Weihai Changqing Ocean Sci & Technol Co Ltd, Weihai 264300, Peoples R China

9.Minist Nat Resources, Inst Oceanog 1, Qingdao 266061, Peoples R China

10.Chinese Acad Sci, Qingdao Inst Bioenergy & Bioproc Technol, Qingdao 266101, Peoples R China

关键词： Seaweed farming; Kelp; Carbonate dynamics; Environmental effects; CO2 sink or source

期刊名称：AGRICULTURE ECOSYSTEMS & ENVIRONMENT （ 影响因子：6.6； 五年影响因子：6.7 ）

ISSN： 0167-8809

年卷期： 2024 年 361 卷

页码：

收录情况： SCI

摘要： Seaweed farming contributes substantial amounts of organic carbon to the ocean, part of which can be locked for a long term in the ocean and perform the function of ocean carbon sequestration, and the other part can be converted into inorganic carbon through microbial mineralization and aerobic respiration, affecting the pCO2, pHT and dissolved oxygen of seawater. It is generally believed that seaweed farming will cause the seawater to become a sink of CO2 due to carbon fixation by macroalgal photosynthesis. However, little attention has been paid to the fact that seaweed farming environment may sometimes become a source rather than a sink of CO2. Here, through in-situ mesocosm cultivation experiments and eight field investigations covering different kelp growth stages in an intensive farming area in China, we found that compared with the surrounding seawater without kelps, the seawater at the fast-growth stage of kelp was a sink of CO2 (pCO2 decreased by 17-73 mu atm), but became a source of CO2 at the aging stage of kelp (pCO2 increased by 20-37 mu atm). Concurrently, seawater pHT experienced a transition from increase (by 0.02-0.08) to decline (by 0.03-0.04). In-situ mesocosm cultivation experiments showed that the positive environmental effects (i.e., pCO2 decrease and pHT increase) induced by kelps at the early growth stage could be offset within only 3 days at the late-growth and aging stages. The release of dissolved organic carbon by kelps at the late growth stage increased significantly, supporting the enhancement in microbial abundance and respiration, which was manifested by the remarkable decrease in seawater dissolved oxygen, ultimately leading to CO2 release exceeding photosynthetic CO2 absorption. This study suggests that mature farmed kelps should be harvested in time to best utilize their carbon sink function and environmental benefits, which has guiding significance for the rational management of seaweed farming.