厦门大学王为磊教授和美国加州大学 Primeau, Franois W. 的研究小组，在基于多年代际水文数据对生物碳泵进行估算的研究中取得新成果。相关论文于2023年12月6日发表在《自然》杂志上。

研究统计几十年的水文观测数据，通过逆向生物地球化学模型，对 BCP 的强度进行了自上而下的估计。该模型隐含了所有已知的输出途径。研究估计在 73.4 m(模型透光层深度)的总有机碳(TOC)输出量为 15.00±1.12 Pg C year^-1，由于上层水柱中有机质的快速再矿化，只有三分之二的有机碳到达到 100 m 左右的深度。

真光层以下按固存时间划分，τ， τ 大于 3 个月的全球综合有机碳生产率为11.09±1.02 Pg C year^-1，τ 大于 1 年下降到 8.25±0.30 Pg C year^-1，其中 81% 是由于沉降颗粒和垂直迁移的浮游动物造成的非平流扩散垂直通量。然而，通过溶解物质和悬浮颗粒的混合和其他流体运输输出有机碳，对于满足呼吸碳需求仍然具有重要的区域意义。此外，从研究反演中推断出的固存效率的温度依赖性表明，未来的全球变暖可能会加强上层海洋有机质的再循环，从而潜在地削弱 BCP。

据介绍，光合作用产生的有机碳从地表转移到中上层水域，从大气中吸收二氧化碳。然而，目前基于观察的估计与这种生物碳泵(BCP)的强度不统一。地球系统模型(ESMs)也显示出 BCP 估计值的广泛分布，表明对已知碳输出途径的代表有限。

附：英文原文

Title: Biological carbon pump estimate based on multidecadal hydrographic data

Author: Wang, Wei-Lei, Fu, Weiwei, Le Moigne, Frdric A. C., Letscher, Robert T., Liu, Yi, Tang, Jin-Ming, Primeau, Franois W.

Issue&Volume: 2023-12-06

Abstract: The transfer of photosynthetically produced organic carbon from surface to mesopelagic waters draws carbon dioxide from the atmosphere. However, current observation-based estimates disagree on the strength of this biological carbon pump (BCP). Earth system models (ESMs) also exhibit a large spread of BCP estimates, indicating limited representations of the known carbon export pathways. Here we use several decades of hydrographic observations to produce a top-down estimate of the strength of the BCP with an inverse biogeochemical model that implicitly accounts for all known export pathways. Our estimate of total organic carbon (TOC) export at 73.4m (model euphotic zone depth) is 15.00±1.12 Pg C year^-1, with only two-thirds reaching 100m depth owing to rapid remineralization of organic matter in the upper water column. Partitioned by sequestration time below the euphotic zone, τ, the globally integrated organic carbon production rate with τ>3 months is 11.09±1.02 Pg C year^-1, dropping to 8.25±0.30PgCyear1 for τ>1 year, with 81% contributed by the non-advective-diffusive vertical flux owing to sinking particles and vertically migrating zooplankton. Nevertheless, export of organic carbon by mixing and other fluid transport of dissolved matter and suspended particles remains regionally important for meeting the respiratory carbon demand. Furthermore, the temperature dependence of the sequestration efficiency inferred from our inversion suggests that future global warming may intensify the recycling of organic matter in the upper ocean, potentially weakening the BCP.

DOI: 10.1038/s41586-023-06772-4

Source: https://www.nature.com/articles/s41586-023-06772-4