Nutrient co-limitation at the boundary of an oceanic gyre
Nutrient co-limitation at the boundary of an oceanic gyre
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DOI：
10.1038/nature24063
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发表时间：
2017-11-09
期刊：
影响因子：
64.8
通讯作者：
Moore, C. Mark
中科院分区：
文献类型：
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作者：
Browning, Thomas J.;Achterberg, Eric P.;Moore, C. Mark
海洋初级生产的营养限制对海洋食物网和进入深海的碳通量起着根本的控制作用(1)。贫营养副热带环流的广阔边界共同定义了海洋生产力的最极端转变，但对这些区域的营养限制知之甚少（1-4）。在这里，我们提出了在南大西洋环流东部边界进行的全因子营养修正实验的结果。我们发现，在广泛的区域，单独添加氮或铁在48小时内没有显著的浮游植物生长。然而，氮和铁的添加使叶绿素a的浓度增加了约40倍，导致硅藻增殖，并降低了群落多样性。一旦氮铁共生限制得到缓解，添加钴或含钴的维生素B12可以进一步提高叶绿素a的产量，最高可达三倍。我们的研究结果表明，氮铁共同限制在海洋中普遍存在，其他微量营养素也接近共同缺乏。这种多营养限制可能会增加浮游植物群落的多样性。
Nutrient limitation of oceanic primary production exerts a fundamental control on marine food webs and the flux of carbon into the deep ocean(1). The extensive boundaries of the oligotrophic sub-tropical gyres collectively define the most extreme transition in ocean productivity, but little is known about nutrient limitation in these zones(1-4). Here we present the results of full-factorial nutrient amendment experiments conducted at the eastern boundary of the South Atlantic gyre. We find extensive regions in which the addition of nitrogen or iron individually resulted in no significant phytoplankton growth over 48 hours. However, the addition of both nitrogen and iron increased concentrations of chlorophyll a by up to approximately 40-fold, led to diatom proliferation, and reduced community diversity. Once nitrogen-iron co-limitation had been alleviated, the addition of cobalt or cobalt-containing vitamin B12 could further enhance chlorophyll a yields by up to threefold. Our results suggest that nitrogen-iron co-limitation is pervasive in the ocean, with other micronutrients also approaching co-deficiency. Such multi-nutrient limitations potentially increase phytoplankton community diversity.