近日，西班牙天体生物学中心Fuencisla Cañadas团队研究了海洋中磷循环增强脉冲驱动的太古宙氧绿洲。该研究于2025年4月16日发表在《自然—地球科学》杂志上。
大约24.3亿至21亿年前，地球大气中氧气的首次增加从根本上改变了大气和海洋，为复杂生命的进化奠定了基础。然而，地球化学证据表明，在大气氧气上升之前，海洋中存在间歇性的氧气绿洲，尽管驱动氧气产生和积累的机制仍然受到很好的限制。
研究组展示了加拿大红湖地区29.3亿年钻孔岩芯的氧化还原敏感痕量金属和铁形态数据以及磷相分配结果，以重建海洋磷循环，并将其与主要缺氧、富含铁的太古代海洋中的氧气生产联系起来。该数据记录了已知最早的地表水氧积累间隔之一，比大气氧的首次积累早了约500 Ma。
这些间隔之前是含铁间隔和硫化物可用性增强的间隔，这导致通过沉积物中的缺氧循环，海洋磷的生物利用度急剧增加。提高磷的生物利用度将有助于刺激光合初级生产力和有机碳埋藏，这可能对晚太古代海洋中氧气绿洲的幕式发展起到了主要控制作用。这反过来又导致了含氧表面环境发展的关键过渡阶段。
附：英文原文
Title: Archaean oxygen oases driven by pulses of enhanced phosphorus recycling in the ocean
Author: Caadas, Fuencisla, Guilbaud, Romain, Fralick, Philip, Xiong, Yijun, Poulton, Simon W., Martin-Redondo, Maria-Paz, G. Fairn, Alberto
Issue&Volume: 2025-04-16
Abstract: Earth’s first rise in atmospheric oxygen between about 2.43billion and 2.1billion years ago fundamentally transformed the atmosphere and oceans, setting the foundation for the evolution of complex life. However, geochemical evidence reveals intermittent oceanic oxygen oases before the rise of atmospheric oxygen, although the mechanisms that drove the production and accumulation of oxygen remain poorly constrained. Here we present redox-sensitive trace metal and iron speciation data, and phosphorus phase partitioning results, for a 2.93-billion-year-old drill core from the Red Lake area, Canada, to reconstruct oceanic phosphorus cycling and links to oxygen production in the dominantly anoxic, iron-rich Archaean ocean. Our data document one of the earliest known intervals of surface water oxygen accumulation, predating the first accumulation of atmospheric oxygen by about 500Ma. These intervals were preceded by ferruginous intervals and intervals of enhanced sulfide availability, which led to pulsed increases in oceanic phosphorus bioavailability via anoxic recycling from sediments. Enhanced phosphorus bioavailability would have helped stimulate photosynthetic primary productivity and organic carbon burial, probably exerting a major control on the episodic development of oxygen oases in the late Archaean ocean. This, in turn, led to a critical transitional phase in the development of an oxygenated surface environment.
DOI: 10.1038/s41561-025-01678-4
Source: https://www.nature.com/articles/s41561-025-01678-4