在模拟翻转氧气最小区的过程中,Suboxic DOM对表面的原核生物具有生物可用性,魔鬼洞,百慕大
Rachel J Parsons1,2, Shuting Liu3,4, Krista Longnecker5
1Microbial Ecology Laboratory, Bermuda Institute of Ocean Sciences, St. George's, Bermuda.
Frontiers in microbiology
|January 5, 2024
概括
扩大氧气最小区 (OMZs) 对海洋生态系统产生影响. 这项研究表明,在亚氧水中积累的深层溶解有机碳 (DOC) 在重新氧化后具有生物可用性,促进微生物生长和营养循环.
科学领域:
- 海洋微生物生态学
- 生物地质化学生物地质化学
- 气候变化影响气候变化的影响.
背景情况:
- 由于气候变化,氧气最小区 (OMZ) 正在全球范围内扩大,改变了海洋微生物过程.
- 百慕大的魔鬼洞为研究OMZ微生物生物地质化学提供了一个模型系统,因为它每年分层和翻转周期.
- 气箱状况导致深度溶解有机物 (DOM) 的积累.
研究的目的:
- 为了评估在suboxic水中积累的溶解有机碳 (DOC) 的生物可用性.
- 为了研究微生物群体对亚氧水的再氧化反应的反应.
- 了解DOM在模拟翻转事件期间的命运.
主要方法:
- 模拟翻转实验使用来自百慕大魔鬼洞的0.2微米过物.
- 接种表面 prokaryotic 社区到深层 (suboxic) 过物,反之亦然.
- 监测 prokaryotic 细胞密度,DOC 清除,以及微生物社区组成的变化 (特定功能基因的基因拷贝数,如 amoA 和 cbbL).
主要成果:
- 表面 prokaryotes 很容易消耗从suboxic 水中积累的DOC,从而使细胞密度增加了2.5倍.
- 微生物群落发生了转变,出现了强硬的DOM降解剂 (SAR202) 和化学自营氨氧化古生物 (Nitrosopumilales).
- 接种到地表水中的深水 Prokaryotes 显示了最初的死亡,但转移到异质群体,产生不稳定的 DOM.
结论:
- 在suboxic区域积累的DOM在重新氧化后对表面微生物具有生物可用性.
- 重氧化支持微生物群落的转变,使得不稳定的DOM产生和反抗性的DOM降解成为可能.
- 这些发现突显了微生物对OMZ扩张和颠覆事件的动态反应,影响了碳和营养循环.
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