法国索邦大学 Ricour, Florian 团队在最新研究中，揭示了在海洋中通过生物泵的世纪尺度的碳固存通量。这一研究成果于2023年11月27日发表在国际顶尖学术期刊《自然—地球科学》上。

通常认为，由此产生的生物源溶解无机碳的世纪尺度(≥100 年)固存只发生在深海，通常在 1000 米以下。然而，研究人员在最近的工作发现，在许多海洋区域，碳可以在 1000 米以上，进行世纪尺度的固存，被称为“连续垂直固存”。

研究人员通过结合先前发表的有机碳通量估计值和水质量固存时间分布的模拟值，计算了由生物泵驱动的整个水柱的世纪尺度碳固存通量。研究估计，通过各种生物泵途径的联合作用，在当代海洋中被隔离 ≥100 年的有机碳通量为 0.9-2.6 Pg C yr^-1，这比以前基于到达深海的有机碳通量的估计值大 6 倍。

据悉，海洋的碳含量约是大气的 40 倍，以溶解的无机碳(DIC)的形式固存了3.8万 Pg C，而目前大气中以二氧化碳(CO₂)的形式固存了900 Pg C。生物碳泵以沉降颗粒、垂直迁移生物和物理循环的形式，将有机碳从海洋表面转移到更深的水域，从而有助于海洋碳固存。

附：英文原文

Title: Century-scale carbon sequestration flux throughout the ocean by the biological pump

Author: Ricour, Florian, Guidi, Lionel, Gehlen, Marion, DeVries, Timothy, Legendre, Louis

Issue&Volume: 2023-11-27

Abstract: The ocean contains about 40 times more carbon than the atmosphere, storing 38,000Pg C as dissolved inorganic carbon (DIC) versus 900Pg C as carbon dioxide (CO₂) in the present atmosphere. The biological carbon pump contributes to ocean carbon storage by moving organic carbon out of the surface ocean into deeper waters in sinking particles, vertically migrating organisms and physical circulation. Century-scale (≥100 years) storage of the resulting biogenic DIC is commonly assumed to occur exclusively in the deep ocean, typically below 1,000m. However, recent work has shown that carbon can be sequestered at century scales above 1,000m in many ocean regions, in what we call ‘continuous vertical sequestration’. Here we calculate the century-scale carbon sequestration flux driven by the biological pump throughout the water column by combining previously published estimates of organic carbon flux and modelled values of water-mass sequestration time distributions. We estimate that the flux of organic carbon that is sequestered for ≥100 years in the contemporary ocean by the combined action of various biological pump pathways is 0.9–2.6Pg C yr^-1, which is up to six times larger than previous estimates based on the organic carbon flux reaching the deep ocean.

DOI: 10.1038/s41561-023-01318-9

Source: https://www.nature.com/articles/s41561-023-01318-9