Influence of light and temperature on the marine iron cycle: From theoretical to global modeling
Influence of light and temperature on the marine iron cycle: From theoretical to global modeling
复制标题
光和温度对海洋铁循环的影响：从理论到全局建模
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
K. Arrigo
中科院分区：
文献类型：
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作者：
A. Tagliabue;L. Bopp;O. Aumont;K. Arrigo
铁在许多海洋区域调节净初级生产力（NPP），并以各种不同的形式存在于海水中，并非所有这些都是生物可利用的。我们使用了一个相对复杂的铁循环模型来研究铁形态的变化作为辐照度/温度的函数，并在全球海洋地球化学模型（OBM）中对其一阶影响进行参数化，这需要对铁化学的表示进行某些假设。总的来说，我们发现，较高的辐照度（典型的浅混合层）促进溶解铁（dFe）转化为生物可利用的形式（bFe），并增加bFe浓度5- 53%，这取决于参数值。温度在控制bFe中起次要作用，冷混合层增加bFe浓度。对于给定的辐照度和温度，生物可利用的Fe配体的存在增加bFe/dFe。当存在生物可利用的Fe配体时，则降低光致能力、增加对数条件稳定性或增加此类配体的浓度都起到增加bFe/dFe的作用。这种过程目前在全球OBM中没有表现出来，其中铁通常被参数化为一个池，我们发现，如果包括温度和辐照度对bFe的影响，即使在恒定的循环下，NPP也可以在区域上变化>±20%。此外，铁化学在控制浮游植物铁限制可以减轻的深度和铁基NPP的后续效率方面很重要。我们还建议，有机络合dFe必须是生物利用的，如果浮游植物生物量和常量营养素的分布与观察相一致。我们的研究结果是重要的，在了解的作用，在不断变化的气候下的浮游植物的铁供应的辐照度/混合制度。关于铁形态和速率过程的新数据集将有助于完善我们的模型。
Iron regulates net primary production (NPP) in a number of ocean regions and exists in a variety of different forms in seawater, not all of which are bioavailable. We used a relatively complex iron cycle model to examine variability in iron speciation as a function of irradiance/temperature and parameterize its first‐order impact in a global ocean biogeochemistry model (OBM), which necessitated certain assumptions regarding the representation of iron chemistry. Overall, we find that higher irradiance (typical of shallower mixed layers) promotes the conversion of dissolved iron (dFe) into bioavailable forms (bFe) and increases bFe concentration by 5–53%, depending on parameter values. Temperature plays a secondary role in controlling bFe, with cold mixed layers increasing bFe concentrations. For a given irradiance and temperature, the presence of bioavailable Fe ligands increases bFe/dFe. When bioavailable Fe ligands are present, then reducing the photolability, increasing the log conditional stability, or increasing the concentration of such ligands all act to increase bFe/dFe. Such processes are currently not represented in global OBMs, where iron is typically parameterized as one pool, and we find that NPP can vary by >±20% regionally if the impact of temperature and irradiance on bFe is included, even under a constant circulation. Additionally, iron chemistry is important in controlling the depth over which phytoplankton iron limitation can be alleviated and the subsequent efficiency of iron‐based NPP. We also suggest organically complexed dFe must be bioavailable if distributions of phytoplankton biomass and macronutrients are to be reconciled with observations. Our results are important in understanding the role of the irradiance/mixing regime in governing the supply of iron to phytoplankton under a changing climate. New data sets on iron speciation and rate processes will aid in refining our model.
影响因子：
56.9
作者：
Martinez, JS;Zhang, GP;Butler, A
通讯作者：
Butler, A