Deep sub-seafloor prokaryotes stimulated at interfaces over geological time
Deep sub-seafloor prokaryotes stimulated at interfaces over geological time
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DOI：
10.1038/nature03796
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发表时间：
2005-07-21
期刊：
影响因子：
64.8
通讯作者：
Fry, JC
中科院分区：
文献类型：
--
作者：
Parkes, RJ;Webster, G;Fry, JC
海底生物圈是地球上最大的原核生物栖息地（1），但也是代谢率最低的栖息地（2）。模拟的活性率非常低，表明大多数原核生物可能是不活跃的或代谢非常缓慢（2）。在这里，我们提出的结果，从两个太平洋的网站，边缘和开阔的海洋，这两个都有深，地下刺激与地球化学和/或沉积界面的原核生物过程。在90米深的边缘网站，刺激是这样的，原核生物的数量更高（约13倍）和活动率高于或接近近地表值。对高分子量DNA的分析证实了有活力的原核生物的存在，并显示生物多样性随深度的变化与地球化学相结合，包括在90米界面处的显著群落变化。在开阔的海洋站点，原核生物数量的增加在深度上受到更多的限制，但也对应于活动的增加;然而，这一次，它们与重复的富含钙的沉积物层（约900万年前）有关。这些结果表明，深层沉积的原核生物可以有很高的活动性，有不断变化的多样性与接口和活跃的地质时间尺度。
The sub-seafloor biosphere is the largest prokaryotic habitat on Earth(1) but also a habitat with the lowest metabolic rates(2). Modelled activity rates are very low, indicating that most prokaryotes may be inactive or have extraordinarily slow metabolism(2). Here we present results from two Pacific Ocean sites, margin and open ocean, both of which have deep, subsurface stimulation of prokaryotic processes associated with geochemical and/or sedimentary interfaces. At 90 m depth in the margin site, stimulation was such that prokaryote numbers were higher ( about 13-fold) and activity rates higher than or similar to near-surface values. Analysis of high-molecular-mass DNA confirmed the presence of viable prokaryotes and showed changes in biodiversity with depth that were coupled to geochemistry, including a marked community change at the 90-m interface. At the open ocean site, increases in numbers of prokaryotes at depth were more restricted but also corresponded to increased activity; however, this time they were associated with repeating layers of diatom-rich sediments ( about 9 Myr old). These results show that deep sedimentary prokaryotes can have high activity, have changing diversity associated with interfaces and are active over geological timescales.