Comparing paleo-oxygenation proxies (benthic foraminiferal surface porosity, I/Ca, authigenic uranium) on modern sediments and the glacial Arabian Sea
Comparing paleo-oxygenation proxies (benthic foraminiferal surface porosity, I/Ca, authigenic uranium) on modern sediments and the glacial Arabian Sea
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比较现代沉积物和冰川阿拉伯海的古氧化指标（底栖有孔虫表面孔隙度、I/Ca、自生铀）
DOI：
10.1016/j.gca.2022.06.001
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发表时间：
2022
影响因子：
5
通讯作者：
Costa, Kassandra M.
中科院分区：
文献类型：
--
作者：
Lu, Wanyi;Wang, Yi;Oppo, Delia W.;Nielsen, Sune G.;Costa, Kassandra M.
末次冰期的海洋氧重建需要了解冰川深海碳储存机制和验证气候模式模拟结果。然而，现有的底水氧（BWO）重建由于每种古底水氧（BWO）代理的局限性而具有模糊性。在此，我们从全球分布的岩心顶部样品中提供了三种BWO指标的数据：底栖有孔虫表面孔隙度、底栖有孔虫碘/钙（I/Ca）和自生铀（aU），并评估了这些BWO指标在全球和区域尺度上的潜在优势和局限性。这三种指标对相对较低BWO浓度（< ~ 50µmol/kg）的变化最为敏感。全球分布的岩心顶部数据证实，有孔虫表面孔隙度与BWO在0 ~ 100µmol/kg之间相关。我们的分析进一步证实，底栖生物的表面孔隙度主要是由BWO直接控制的，而不是表面孔隙的其他潜在功能，如有机碳吸收和呼吸二氧化碳释放。低底栖I/Ca值可以识别低BWO(<50µmol/kg)，而高底栖I/Ca值与特定BWO无关，这可能是由于I/Ca对温度、盐度、碳酸盐离子浓度或高BWO下的水质量混合的额外依赖。aU和BWO之间的关系是区域性的。在阿拉伯海，多变的aU富集只发生在氧最小带（OMZ）内，这是由高出口产量和有机质向沉积物的通量驱动的。最后，我们结合有孔虫表面孔隙度、I/Ca和aU，利用现代阿拉伯海OMZ的沉积物岩心进行了第一次冰川-全新世BWO定量重建。3个指标一致表明，阿拉伯海浅层在最近~ 30 kyr的BWO < 50 μmol/kg，冰期的BWO相对高于全新世。与底栖生物碳同位素梯度代理（Δδ13C）的比较证实，Δδ13C高估了低氧环境下的BWO，这可能是由于沉积物成岩作用的影响。我们的研究对这些BWO代理的优点和局限性提供了新的见解，并证实了多代理重建对于更可靠的古BWO估计的重要性。
Oceanic oxygen reconstructions of the last glacial period are needed to understand the mechanisms of glacial deep ocean carbon storage and to validate climate model simulations. However, existing bottom-water oxygen (BWO) reconstructions are ambiguous due to limitations of each paleo-BWO proxy. Here we present data on three proxies for BWO: benthic foraminiferal surface porosity, benthic foraminiferal iodine/calcium (I/Ca), and authigenic uranium (aU), from globally distributed core-top samples, and we evaluate the potential advantages and limitations of these BWO proxies on global and regional scales. All three proxies are most sensitive to changes at relatively low BWO concentrations (<∼50 µmol/kg). Data from globally-distributed core tops confirm that foraminiferal surface porosity is correlated with BWO between 0 and 100 µmol/kg. Our analysis further confirms that benthic surface porosity is predominantly controlled directly by BWO rather than other potential functionalities of surface pores such as organic carbon uptake and respiratory CO2release. Low benthic I/Ca can identify low BWO (<50 µmol/kg), whereas higher benthic I/Ca values are not associated with specific BWO, possibly due to additional dependence of I/Ca on temperature, salinity, carbonate ion concentration, or water mass mixing at higher BWO. The relationship between aU and BWO is regionally dependent. In the Arabian Sea, variable aU enrichments occur only within the Oxygen Minimum Zone (OMZ), driven by high export production and organic matter fluxes to the sediment. Finally, we combine foraminiferal surface porosity, I/Ca and aU to generate the first quantitative glacial-Holocene BWO reconstructions using a sediment core taken from within the modern Arabian Sea OMZ. All three proxies consistently suggest BWO < 50 μmol/kg in the shallow Arabian Sea during the last ∼30 kyr, with relatively higher BWO during the glacial period than the Holocene. A comparison with the benthic carbon isotope gradient proxy (Δδ13C) confirms that Δδ13C over-estimates BWO in low-oxygen settings possibly due to sediment diagenesis impacts. Our study provides new insights on the merits and limitations of these BWO proxies and confirms the importance of multi-proxy reconstructions for more reliable paleo-BWO estimates.
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影响因子：
5.8
作者：
Lu, Zunli;Jenkyns, Hugh C.;Rickaby, Rosalind E. M.
通讯作者：
Rickaby, Rosalind E. M.
中东欧地台Riphean沉积盆地演化阶段(以Kresttsy和Pavlov Posad沉积盆地为例)
DOI：
--
发表时间：
2001
期刊：
影响因子：
--
作者：
V. Kostyleva;N. Chamov;I. M. Simanovich;O. Anikeeva
通讯作者：
O. Anikeeva
影响因子：
--
作者：
M. Tetard;L. Licari;L. Beaufort
通讯作者：
M. Tetard;L. Licari;L. Beaufort
影响因子：
5
作者：
Jiban Podder;Jinru Lin;W. Sun;S. Botis;J. Tse;N. Chen;Yongfeng Hu;D. Li;J. Seaman;Yuanming Pan
通讯作者：
Jiban Podder;Jinru Lin;W. Sun;S. Botis;J. Tse;N. Chen;Yongfeng Hu;D. Li;J. Seaman;Yuanming Pan
评估沉积烯酮以定量重建浮游植物生物量
DOI：
10.1073/pnas.2014787118
发表时间：
2020
期刊：
Proceedings of the National Academy of Sciences
影响因子：
--
作者：
M. Raja;A. Rosell‐Melé
通讯作者：
A. Rosell‐Melé