近日，中国海洋大学王厚杰团队揭示了河流三角洲通过生物圈有机碳埋藏固碳的关键作用。2025年10月27日出版的《地质学》杂志发表了这项成果。

生物圈有机碳（OC）埋藏和成岩OC氧化是全球CO₂浓度调节的基本控制因素。河流三角洲是海洋中最大的OC汇之一，储存了大量来自生物圈和岩石圈的陆地OC。然而，人们三角洲生物圈和岩石成因的OC储存程度仍然知之甚少。

研究组通过地貌学与碳同位素分析，对动态河流三角洲——黄河三角洲的生物源与岩石源有机碳埋藏速率进行量化。黄河三角洲的有机碳埋藏特征表现为：岩石源有机碳埋藏速率最高（109 ± 27 g m⁻² yr⁻¹），其次为前期沉积土壤有机碳（107 ± 27 g m⁻² yr⁻¹）、陆源现代有机碳（87 ± 21 g m⁻² yr⁻¹）和海洋源有机碳（48 ± 16 g m⁻² yr⁻¹）。

该三角洲生物源有机碳埋藏速率（242 g m⁻² yr⁻¹）可达陆缘海全球平均值的70倍。通过分析全球三角洲与陆缘海的生物源与岩石源有机碳埋藏速率及通量，研究组揭示了三角洲作为生物源有机碳重要汇区的关键作用。该研究强调在评估碳汇时，需区分生物源与岩石源有机碳，以更准确界定其对大气二氧化碳浓度的影响。

附：英文原文

Title: Key role of river deltas in carbon sequestration through biospheric organic carbon burial

Author: Taian Lu, Thomas S. Bianchi, Michael R. Shields, Naishuang Bi, Xiao Wu, Limin Hu, Xiaoyan Ning, Houjie Wang

Issue&Volume: 2025-10-27

Abstract: Biospheric organic carbon (OC) burial and petrogenic OC oxidation are fundamental controls in the regulation of global CO2 concentrations. River deltas are among the largest OC sinks in the ocean, storing substantial amounts of terrestrial OC originating from both the biosphere and lithosphere. However, the extent of biospheric and petrogenic OC storage in deltas remains poorly understood. Here, we quantified biospheric and petrogenic OC burial rates in a dynamic river delta, the Yellow River Delta, using geomorphology and carbon isotopic analyses. The Yellow River Delta is characterized by high burial rates of petrogenic OC (109 ± 27 g m2 yr1) and pre-aged soil OC (107 ± 27 g m2 yr1), followed by terrestrial modern OC (87 ± 21 g m2 yr1) and marine OC (48 ± 16 g m2 yr1). The deltaic biospheric OC burial rate (242 g m2 yr1) is up to 70 times higher than the global average in marginal seas. By analyzing biospheric and petrogenic OC burial rates and fluxes in global deltas and marginal seas, we highlight the critical role of deltas as major sinks for biospheric OC. This study underscores the importance of distinguishing between biospheric and petrogenic OC when assessing carbon sinks to better constrain their influence on atmospheric CO2 levels.

DOI: 10.1130/G53573.1

Source: https://pubs.geoscienceworld.org/gsa/geology/article-abstract/doi/10.1130/G53573.1/662156/Key-role-of-river-deltas-in-carbon-sequestrationredirectedFrom=fulltext