Li Yuan, Fu Chuancheng, Ye Chenglong, Song Zhaoliang, Kuzyakov Yakov, Vancov Tony, Guo Laodong, Luo Zhongkui, Van Zwieten Lukas, Wang Yidong, Luo Yu, Wang Weiqi, Zeng Lin, Han Guangxuan, Wang Hailong, Luo Yongming
CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, China.
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China.
Glob Chang Biol. 2025 Jan;31(1):e70019. doi: 10.1111/gcb.70019.
Coastal wetlands contain very large carbon (C) stocks-termed as blue C-and their management has emerged as a promising nature-based solution for climate adaptation and mitigation. The interactions among sources, pools, and molecular compositions of soil organic C (SOC) within blue C ecosystems (BCEs) remain elusive. Here, we explore these interactions along an 18,000 km long coastal line of salt marshes, mangroves, and seagrasses in China. We found that mineral-associated organic C (MAOC) is enriched in BCEs dominated by allochthonous inputs and abundant active minerals, leading to an increased proportion of persistent organic molecules. Specifically, soils with large allochthonous inputs (> 50%) are characterized by a substantial contribution of MAOC (> 70%) to total SOC with a notable preservation of lipids (36%) across salt marshes, mangroves, and seagrasses. The burial of allochthonous particles, derived from external sources such as rivers or tidal influxes, facilitates the formation of stable MAOC through binding to mineral surfaces or occlusion within microaggregates. The proportions of particulate organic C (POC) and MAOC are important predictors for molecular compositions of soil organic matter. Lipid proportions within molecular composition decrease as POC and autochthonous C proportions increase. These findings provide new insights into the coupled control over SOC sequestration in BCEs, emphasizing the role of allochthonous inputs, proportions of carbon pools, and persistent organic components.
沿海湿地储存着大量的碳（C），即所谓的“蓝碳”，其管理已成为一种有前景的基于自然的气候适应和缓解解决方案。蓝碳生态系统（BCEs）中土壤有机碳（SOC）的来源、库和分子组成之间的相互作用仍不明确。在此，我们沿着中国18000公里长的盐沼、红树林和海草海岸线探索了这些相互作用。我们发现，在以异地输入和丰富的活性矿物为主的蓝碳生态系统中，与矿物相关的有机碳（MAOC）含量丰富，导致持久性有机分子的比例增加。具体而言，异地输入量大（>50%）的土壤的特征是，MAOC对总SOC的贡献很大（>70%），并且在盐沼、红树林和海草中脂质保存显著（36%）。来自河流或潮汐涌入等外部来源的异地颗粒的埋藏，通过与矿物表面结合或在微团聚体内包藏，促进了稳定的MAOC的形成。颗粒有机碳（POC）和MAOC的比例是土壤有机质分子组成的重要预测指标。随着POC和本地碳比例的增加，分子组成中的脂质比例降低。这些发现为蓝碳生态系统中SOC固存的耦合控制提供了新的见解，强调了异地输入、碳库比例和持久性有机成分的作用。
