Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo, Zhejiang, China.
State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, Zhejiang, China.
Glob Chang Biol. 2023 Dec;29(24):6856-6866. doi: 10.1111/gcb.16990. Epub 2023 Oct 19.
Marine primary producers are largely dependent on and shape the Earth's climate, although their relationship with climate varies over space and time. The growth of phytoplankton and associated marine primary productivity in most of the modern global ocean is limited by the supply of nutrients, including the micronutrient iron. The addition of iron via episodic and frequent events drives the biological carbon pump and promotes the sequestration of atmospheric carbon dioxide (CO ) into the ocean. However, the dependence between iron and marine primary producers adaptively changes over different geological periods due to the variation in global climate and environment. In this review, we examined the role and importance of iron in modulating marine primary production during some specific geological periods, that is, the Great Oxidation Event (GOE) during the Huronian glaciation, the Snowball Earth Event during the Cryogenian, the glacial-interglacial cycles during the Pleistocene, and the period from the last glacial maximum to the late Holocene. Only the change trend of iron bioavailability and climate in the glacial-interglacial cycles is consistent with the Iron Hypothesis. During the GOE and the Snowball Earth periods, although the bioavailability of iron in the ocean and the climate changed dramatically, the changing trend of many factors contradicted the Iron Hypothesis. By detangling the relationship among marine primary productivity, iron availability and oceanic environments in different geological periods, this review can offer some new insights for evaluating the impact of ocean iron fertilization on removing CO from the atmosphere and regulating the climate.
海洋初级生产者在很大程度上依赖于地球气候，并对其产生影响，尽管它们与气候的关系因空间和时间而异。在现代全球海洋的大部分区域，浮游植物的生长和相关的海洋初级生产力受到营养物质供应的限制，包括微量元素铁。通过间歇性和频繁的事件添加铁会驱动生物碳泵，并促进大气二氧化碳（CO）向海洋的封存。然而，由于全球气候和环境的变化，铁与海洋初级生产者之间的依赖关系在不同地质时期会自适应地发生变化。在这篇综述中，我们研究了铁在调节某些特定地质时期海洋初级生产力方面的作用和重要性，即休伦冰期的大氧化事件（GOE）、冰川纪的雪球地球事件、更新世的冰期-间冰期循环以及从末次冰盛期到全新世晚期的时期。只有冰期-间冰期循环中铁的生物可利用性和气候的变化趋势与铁假说一致。在 GOE 和雪球地球时期，尽管海洋中铁的生物可利用性和气候发生了剧烈变化，但许多因素的变化趋势与铁假说相矛盾。通过梳理不同地质时期海洋初级生产力、铁的可用性和海洋环境之间的关系，本综述可以为评估海洋铁施肥对从大气中去除 CO 和调节气候的影响提供一些新的见解。
