Zhang Jingfan, Gan Shuchai, Yang Pingjian, Zhou Jinge, Huang Xingyun, Chen Han, He Hua, Saintilan Neil, Sanders Christian J, Wang Faming
Xiaoliang Research Station of Tropical Coastal Ecosystems, Key Laboratory of Vegetation and Management of Degraded Ecosystems, the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, and Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, P.R. China.
University of Chinese Academy of Sciences, Beijing, P.R. China.
Nat Commun. 2024 Oct 18;15(1):8994. doi: 10.1038/s41467-024-53413-z.
Mangroves can retain both autochthonous and allochthonous marine and/or terrestrial organic carbon (OC) in sediments. Accurate quantification of these OC sources is essential for the proper allocation of blue C credits. Here, we conduct a global-scale analysis of sediments autochthonous and allochthonous OC contributions in estuarine and marine mangroves using stable isotopes. Globally, mangrove-derived autochthonous OC was the main contributor to estuarine and marine mangrove top-meter soil organic carbon (SOC) (49% and 62%, respectively). Less marine allochthonous OC (21%) was deposited than terrestrial allochthonous OC (30%) in estuarine mangrove sediments. Estuarine mangroves accumulated more SOC in sediments than marine mangroves (282 ± 8.1 Mg C ha and 250 ± 5.0 Mg C ha, respectively), primarily due to the additional terrestrial OC inputs. Globally, marine mangroves held 67% of the total mangrove SOC, reaching 3025 ± 345 Tg C, while 1502 ± 154 Tg C was stored in estuarine mangrove sediments. The findings emphasize the substantial influence of coastal environmental settings on OC contributions, underlining the necessity of accurate OC source quantification for the effective allocation of blue carbon credits.
红树林可以在沉积物中保留本地和异地的海洋和/或陆地有机碳（OC）。准确量化这些有机碳来源对于合理分配蓝碳信用至关重要。在此，我们利用稳定同位素对河口和海洋红树林沉积物中的本地和异地有机碳贡献进行了全球尺度分析。在全球范围内，红树林衍生的本地有机碳是河口和海洋红树林表层一米土壤有机碳（SOC）的主要贡献者（分别为49%和62%）。在河口红树林沉积物中，沉积的海洋异地有机碳（21%）比陆地异地有机碳（30%）少。河口红树林沉积物中积累的土壤有机碳比海洋红树林多（分别为282±8.1 Mg C/ha和250±5.0 Mg C/ha），这主要是由于额外的陆地有机碳输入。在全球范围内，海洋红树林储存了红树林土壤有机碳总量的67%，达到3025±345 Tg C，而河口红树林沉积物中储存了1502±154 Tg C。研究结果强调了沿海环境对有机碳贡献的重大影响，突出了准确量化有机碳来源对于有效分配蓝碳信用的必要性。
