Seagrass litter is a crucial autochthonous source of sediment organic carbon (Corg) that contributes to Corg storage in coastal ecosystems. However, our understanding of seagrass litter decomposition effects on sediment Corg sequestration and the factors influencing the capacity for autochthonous carbon sequestration remains limited. We investigated Zostera marina litter decomposition dynamics in eelgrass meadows along the Korean coast by monitoring changes in the remaining litter mass and autochthonous Corg during the decomposition process. We used a double‐component exponential decay models to characterize the decomposition dynamics and estimate the autochthonous Corg remaining. We also identified potential factors affecting litter decay and Corg accumulation in sediments by examining site‐specific physicochemical properties. Our findings revealed that double‐component models effectively characterized litter decomposition dynamics and indicated greater preservation of litter‐derived slowly degrading Corg in sediments. The reduced decomposition of litter materials owing to low oxygen availability in the muddy sediments led to greater retention of litter mass and litter‐derived Corg in sediments. The anoxic conditions of below‐ground litterbags, compared with above‐ground litterbags, could be alleviated by the oxygen transport through fresh Z. marina roots, thereby potentially stimulating the microbial decomposition of Z. marina below‐ground litter materials at these sites. Our findings highlight the importance of understanding litter decomposition dynamics to accurately assess the carbon sink capacity of seagrass meadows, and demonstrate that physicochemical properties can influence seagrass litter decomposition.

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海草凋落物分解在确定蓝碳汇容量中的作用

海草凋落物是沉积物有机碳（C组织）对C有贡献组织沿海生态系统的储存。然而，我们对海草凋落物分解对沉积物 C 影响的理解组织碳封存以及影响本地碳封存能力的因素仍然有限。我们调查了大叶藻通过监测剩余凋落物质量和本土碳的变化，研究韩国沿海鳗草草甸的凋落物分解动态组织在分解过程中。我们使用双分量指数衰减模型来表征分解动力学并估计本地 C组织其余的。我们还确定了影响凋落物腐烂和 C 的潜在因素组织通过检查特定地点的物理化学性质来确定沉积物中的积累。我们的研究结果表明，双组分模型有效地表征了凋落物分解动力学，并表明更好地保存了来自凋落物的缓慢降解的 C组织在沉积物中。由于泥质沉积物中的氧气含量低，凋落物材料的分解减少，导致凋落物质量和来自凋落物的碳的保留量更大组织在沉积物中。与地上垃圾袋相比，地下垃圾袋的缺氧状况可以通过新鲜垃圾的氧气输送来缓解。Z. 玛丽娜根部，从而潜在地刺激微生物分解Z. 玛丽娜这些地点的地下垃圾材料。我们的研究结果强调了了解凋落物分解动力学对于准确评估海草草甸碳汇能力的重要性，并证明物理化学特性可以影响海草凋落物分解。