The role of seasonal hypoxia and benthic boundary layer exchange on iron redox cycling on the Oregon shelf
The role of seasonal hypoxia and benthic boundary layer exchange on iron redox cycling on the Oregon shelf
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季节性缺氧和底栖边界层交换对俄勒冈陆架铁氧化还原循环的作用
DOI：
10.1002/lno.12476
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发表时间：
2023
影响因子：
4.5
通讯作者：
Moffett, James W.
中科院分区：
文献类型：
--
作者：
Evans, Natalya;Floback, Alexis E.;Gaffney, Justin;Chace, Peter J.;Luna, Zachary;Knoery, Joël;Reimers, Clare E.;Moffett, James W.
广泛的缺氧季节性地发生在俄勒冈大陆架上，近年来缺氧事件的持续时间、强度和频率都有所增加。在缺氧地区，铁还原可以从陆架沉积物中释放出溶解的铁（II）。在2022年夏季，使用微量金属清洁玫瑰结和高分辨率底栖梯度采样器测量了俄勒冈海岸大陆架和斜坡上水柱中的铁（II）。夏季，俄勒冈大陆架底部水域的Fe（II）浓度异常高（40-60 nM），反映了当时的低氧条件（40-70 μM）。观察到的铁（II）与底水氧浓度之间的负相关与基于先前工作的预期一致，表明氧是底水铁通量的主要决定因素。底栖边界层（距离海底1m以内）的Fe（II）快速衰减可能反映了有效的跨大陆架平流。一个以Heceta Bank（~ 44°N）为中心的区域是俄勒冈大陆架上铁释放的热点，可能是由于其半保留性质和沉积物中高含量的泥浆含量。结果表明，缺氧是俄勒冈陆架水域铁储量的重要决定因素，因此最终控制了大陆边缘来源的铁对北太平洋盆地内部的重要性。
Widespread hypoxia occurs seasonally across the Oregon continental shelf, and the duration, intensity, and frequency of hypoxic events have increased in recent years. In hypoxic regions, iron reduction can liberate dissolved Fe(II) from continental shelf sediments. Fe(II) was measured in the water column across the continental shelf and slope on the Oregon coast during summer 2022 using both a trace metal clean rosette and a high‐resolution benthic gradient sampler. In the summer, Fe(II) concentrations were exceptionally high (40–60 nM) within bottom waters and ubiquitous across the Oregon shelf, reflecting the low oxygen condition (40–70 μM) at that time. The observed inverse correlation between Fe(II) and bottom water oxygen concentrations is in agreement with expectations based on previous work that demonstrates oxygen is a major determinant of benthic Fe fluxes. Rapid attenuation of Fe(II) from the benthic boundary layer (within 1 m of the seafloor) probably reflects efficient cross‐shelf advection. One region, centered around Heceta Bank (~ 44°N) acts a hotspot for Fe release on the Oregon continental shelf, likely due to its semi‐retentive nature and high percent mud content in sediment. The results suggest that hypoxia is an important determinant of the inventory of iron is Oregon shelf waters and thus ultimately controls the importance of continental margin‐derived iron to the interior of the North Pacific Basin.
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上升流间歇性在俄勒冈陆架缺氧和氮流失发展中的作用
影响因子：
2.8
作者：
Alexander Galán;M. J. Zirbel;G. Saldías;F. Chan;Ricardo M Letelier
通讯作者：
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影响因子：
56.9
作者：
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通讯作者：
S. Gaines
DOI：
10.1002/lom3.10279
发表时间：
2018-09
期刊：
Limnology and Oceanography: Methods
影响因子：
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作者：
K. Bolster;M. Heller;J. Moffett
通讯作者：
K. Bolster;M. Heller;J. Moffett
影响因子：
11.4
作者：
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通讯作者：
M. Lohan;K. Bruland
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影响因子：
5.2
作者：
S. Siedlecki;A. Mahadevan;D. Archer
通讯作者：
D. Archer