中国地质大学（武汉）罗根明等人合作，研究了白垩纪温室世界中甲烷为燃料的湖泊浮游食物网。这一研究成果于2024年10月21日发表在国际顶尖学术期刊《美国科学院院刊》上。

据悉，甲烷（CH₄）是一种强效的温室气体，也是一些湖泊食物网重要的碳和能量基质。因此，了解甲烷如何融入食物网对于揭示甲烷循环，及其对气候和生态系统的影响至关重要。然而，在全新世之前，特别是在地球历史上的温室气候时期，以甲烷为燃料的湖泊食物网受到的关注相对较少。

研究人员展示了白垩纪海洋缺氧事件1a （约120Mya）期间，以甲烷为燃料的浮游食物网的长期记录，作为未来变暖的地质模拟。研究发现，在这一事件中，产甲烷菌和CH₄-氧化菌（高达87%的产藿烷类细菌）都有异常强烈的扩张。

浮游动物（占纤毛虫饮食的47%）在化学跃层内以CH₄-氧化细菌为食，将大量的CH₄衍生碳转移到更高的营养水平，代表了水体中重要的CH₄汇。结果表明，随着地球变暖，微生物CH₄循环可以重构食物网，并从根本上改变湖泊生态系统中的碳和能量流动以及营养途径。

附：英文原文

Title: Methane fueled lake pelagic food webs in a Cretaceous greenhouse world

Author: Sun, Funing, Luo, Genming, Pancost, Richard D., Dong, Zhengkun, Li, Zhiguo, Wang, Hongmei, Chen, Zhong-Qiang, Xie, Shucheng

Issue&Volume: 2024-10-21

Abstract: Methane (CH₄) is a potent greenhouse gas but also an important carbon and energy substrate for some lake food webs. Understanding how CH₄ incorporates into food webs is, therefore, crucial for unraveling CH₄ cycling and its impacts on climate and ecosystems. However, CH₄-fueled lake food webs from pre-Holocene intervals, particularly during greenhouse climates in Earth history, have received relatively little attention. Here, we present a long-term record of CH₄-fueled pelagic food webs across the Cretaceous Oceanic Anoxic Event 1a (~120 Mya) that serves as a geological analog to future warming. We show an exceptionally strong expansion of both methanogens and CH₄-oxidizing bacteria (up to 87% of hopanoid-producing bacteria) during this Event. Grazing on CH₄-oxidizing bacteria by zooplankton (up to 47% of ciliate diets) within the chemocline transferred substantial CH₄-derived carbon to the higher trophic levels, representing an important CH₄ sink in the water column. Our findings suggest that as Earth warms, microbial CH₄ cycling could restructure food webs and fundamentally alter carbon and energy flows and trophic pathways in lake ecosystems.

DOI: 10.1073/pnas.2411413121

Source: https://www.pnas.org/doi/abs/10.1073/pnas.2411413121