清华大学黄小猛和美国康奈尔大学Luo Yiqi的团队研究发现微生物碳利用效率促进全球土壤碳储存。该研究于2023年5月24日发表于国际一流学术期刊《自然》杂志上。

研究团队使用全球规模的数据集、微生物过程显示模型、数据同化、深度学习和元分析组合，讨论了土壤有机碳储存和微生物碳利用效率之间的关系，以及与气候、植被和土壤性质的相互作用。研究发现，在确定全球有机碳储量及其空间变化方面，微生物碳利用效率的重要性至少是其他评估因素(如碳输入、分解或垂直运输)的四倍。此外，微生物碳利用效率与土壤有机碳含量呈正相关。研究结果指出，微生物碳利用效率是全球有机碳储量的主要决定因素。理解微生物过程及其环境依赖性可能有助于预测土壤有机碳对气候变化的反馈。

据介绍，土壤比其他陆地生态系统储存更多的碳。土壤有机碳(SOC)如何形成和持续化仍然存在争议，这使得人们在理解它如何响应气候变化上具挑战性。有学者提出，土壤微生物在土壤有机碳的形成、保存和流失中起着重要的作用。尽管微生物通过多种途径影响土壤有机质的积累和流失，但微生物碳利用效率(CUE)是一个综合指标，可以捕捉这些过程的平衡。虽然微生物碳利用效率有可能作为土壤有机碳储存变化的预测因素，但微生物碳利用效率在土壤有机碳持久性中的作用仍然未知。

附：英文原文

Title: Microbial carbon use efficiency promotes global soil carbon storage

Author: Tao, Feng, Huang, Yuanyuan, Hungate, Bruce A., Manzoni, Stefano, Frey, Serita D., Schmidt, Michael W. I., Reichstein, Markus, Carvalhais, Nuno, Ciais, Philippe, Jiang, Lifen, Lehmann, Johannes, Wang, Ying-Ping, Houlton, Benjamin Z., Ahrens, Bernhard, Mishra, Umakant, Hugelius, Gustaf, Hocking, Toby D., Lu, Xingjie, Shi, Zheng, Viatkin, Kostiantyn, Vargas, Ronald, Yigini, Yusuf, Omuto, Christian, Malik, Ashish A., Peralta, Guillermo, Cuevas-Corona, Rosa, Di Paolo, Luciano E., Luotto, Isabel, Liao, Cuijuan, Liang, Yi-Shuang, Saynes, Vinisa S., Huang, Xiaomeng, Luo, Yiqi

Issue&Volume: 2023-05-24

Abstract: Soils store more carbon than other terrestrial ecosystems. How soil organic carbon (SOC) forms and persists remains uncertain, which makes it challenging to understand how it will respond to climatic change. It has been suggested that soil microorganisms play an important role in SOC formation, preservation and loss. Although microorganisms affect the accumulation and loss of soil organic matter through many pathways, microbial carbon use efficiency (CUE) is an integrative metric that can capture the balance of these processes. Although CUE has the potential to act as a predictor of variation in SOC storage, the role of CUE in SOC persistence remains unresolved. Here we examine the relationship between CUE and the preservation of SOC, and interactions with climate, vegetation and edaphic properties, using a combination of global-scale datasets, a microbial-process explicit model, data assimilation, deep learning and meta-analysis. We find that CUE is at least four times as important as other evaluated factors, such as carbon input, decomposition or vertical transport, in determining SOC storage and its spatial variation across the globe. In addition, CUE shows a positive correlation with SOC content. Our findings point to microbial CUE as a major determinant of global SOC storage. Understanding the microbial processes underlying CUE and their environmental dependence may help the prediction of SOC feedback to a changing climate.

DOI: 10.1038/s41586-023-06042-3

Source: https://www.nature.com/articles/s41586-023-06042-3