The role of iron sources and transport for Southern Ocean productivity
The role of iron sources and transport for Southern Ocean productivity
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DOI：
10.1016/j.dsr.2014.02.003
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发表时间：
2014-05-01
影响因子：
2.4
通讯作者：
Heywood, Karen J.
中科院分区：
文献类型：
--
作者：
Wadley, Martin R.;Jickells, Timothy D.;Heywood, Karen J.
铁已被发现限制海洋中高营养、低叶绿素区域的初级生产力，包括南大洋。在这里，我们评估的相对大小和地理分布的铁源（沉积，大气，冰山和海冰）的南大洋，以及它们对生产力的影响。基于初级生产力的铁限制和光限制的假设，提出了一个铁循环模式，并将其嵌入到一个涡旋分辨的海洋环流模式中。我们发现，注入深度的各种铁的投入决定其可用性驱动生产，因为溶解铁可能会被清除之前，它进入照明混合层，它可以驱动初级生产。该模型表明，生产主要是由沉积物衍生的铁源，而不是冰山，海冰或大气尘埃。我们注意到非线性响应生产力的变化，一个或多个铁源的强度，由于清除。海冰通过改变真光层铁供应的时间来影响生产力。我们还表明，在斯科舍海的大部分生产力是由沉积物来源的铁从南极半岛，与其他地方热点驱动的岛屿来源。(c)2014爱思唯尔有限公司版权所有。
Iron has been found to limit primary productivity in high nutrient, low chlorophyll regions of the oceans, including the Southern Ocean. Here we assess the relative magnitudes and geographical distributions of the sources of iron (sedimentary, atmospheric, icebergs and sea ice) to the Southern Ocean, and their impact on productivity. We present an iron cycling model, based on the assumptions of iron and light limitation of primary production, which is embedded in an eddy resolving ocean general circulation model. We find that the injection depth of the various iron inputs determines their availability for driving production because dissolved iron may be scavenged prior to it entering the illuminated mixed layer where it can drive primary production. The model suggests that production is predominantly regulated by sediment-derived iron sources rather than icebergs, sea ice or atmospheric dust. We note non-linear response in productivity to changes in the strength of one or more iron sources due to scavenging. Sea ice influences productivity by modifying the timing of iron supply to the euphotic zone. We also show that in the Scotia Sea the majority of productivity is driven by sediment-sourced iron from the Antarctic Peninsula, with additional local hotspots driven by island sources. (c) 2014 Elsevier Ltd. All rights reserved.