Boron isotope-based seasonal paleo-pH reconstruction for the Southeast Atlantic - A multispecies approach using habitat preference of planktonic foraminifera
Boron isotope-based seasonal paleo-pH reconstruction for the Southeast Atlantic - A multispecies approach using habitat preference of planktonic foraminifera
复制标题
基于硼同位素的东南大西洋季节性古 pH 值重建——利用浮游有孔虫栖息地偏好的多物种方法
DOI：
10.1016/j.epsl.2018.02.002
复制
发表时间：
2018
影响因子：
5.3
通讯作者：
Kučera
中科院分区：
文献类型：
--
作者：
Raitzsch;Benthien;Richter;Steinhoefel;Kučera
浮游有孔虫壳方解石的硼同位素组成（δ 11bcc）为钙化时环境水的pH提供了有价值的信息。因此，如果有关于第二碳酸盐体系参数、温度和盐度的信息，地表浮游有孔虫化石的δ 11bcc可以用来重建古代水体pco2。然而，地表水的pH和pco2可能随季节变化，主要是由于温度、DIC和碱度的变化。浮游有孔虫的壳通量也显示出与年内温度变化有关的物种特有的季节模式，因此某些物种的δ 11bcc明显反映了pH，因此pco2偏向于一年内的特定时间段。这对于解释可能反映季节pH信号的化石δ 11 B Cc记录非常重要。本文采用多收集器电感耦合质谱（MC-ICPMS）对浮游有孔虫Globigerina bulloides、Globigerinoides rubber、Trilobatus sacculifer和Orbulina universa进行了δ 11b Cc核心数据分析，并与季节分解碳酸盐体系参数所得的δ 11b硼酸盐数据进行了比较。我们发现，推断出的经季节调整的δ 11 B Cc/δ 11 B硼酸盐关系与现有的校准相似，可以与已发表的δ 11 B Cc野外和培养数据相结合，以增强古ph校准。为了测试这些校准的适用性，我们使用了在东南大西洋沃尔维斯山脊钻取的岩心，在过去的33万年中重建了地表水pCO 2的变化。基于G. bulloides的重建结果与Vostok冰芯数据非常相似，表明在较冷的春季，地表水的pco2与大气接近平衡。相比之下，从主要生活在温暖季节的O. universa、T. sacullifer和G. ruber的δ 11 B Cc估算的pco2值比Vostok冰芯数据高出约50 ppmv。这可能是由于南方夏季和秋季的温度较高，Mg/Ca比较冷的春季平均高~ 4°C，导致pco2每1°C增加~ 4%。我们的研究结果表明，基于δ 11 B Cc的古ph估计包含一个重要的季节信号，反映了记录有孔虫物种的栖息地偏好。
The boron isotopic composition of planktonic foraminiferal shell calcite (δ 11 B Cc) provides valuable information on the pH of ambient water at the time of calcification. Hence, δ 11 B Cc of fossil surface-dwelling planktonic foraminifera can be used to reconstruct ancient aqueous pCO 2 if information on a second carbonate system parameter, temperature and salinity is available. However, pH and pCO 2 of surface waters may vary seasonally, largely due to changes in temperature, DIC, and alkalinity. As also the shell fluxes of planktonic foraminifera show species-specific seasonal patterns that are linked to intra-annual changes in temperature, it is obvious that δ 11 B Cc of a certain species reflects the pH and thus pCO 2 biased towards a specific time period within a year. This is important to consider for the interpretation of fossil δ 11 B Cc records that may mirror seasonal pH signals. Here we present new Multi-Collector Inductively Coupled Mass Spectrometry (MC-ICPMS) δ 11 B Cc coretop data for the planktonic foraminifera species Globigerina bulloides, Globigerinoides ruber, Trilobatus sacculifer and Orbulina universa and compare them with δ 11 B borate derived from seasonally resolved carbonate system parameters. We show that the inferred season-adjusted δ 11 B Cc/δ 11 B borate relationships are similar to existing calibrations and can be combined with published δ 11 B Cc field and culture data to augment paleo-pH calibrations. To test the applicability of these calibrations, we used a core drilled on the Walvis Ridge in the Southeast Atlantic spanning the last 330,000 years to reconstruct changes in surface-water pCO 2. The reconstruction based on G. bulloides, which reflects the austral spring season, was shown to yield values that closely resemble the Vostok ice-core data indicating that surface-water pCO 2 was close to equilibrium with the atmosphere during the cooler spring season. In contrast, pCO 2 estimated from δ 11 B Cc of O. universa, T. sacculifer and G. ruber that predominantly lived during the warmer seasons, exhibits up to∼ 50 ppmv higher values than the Vostok ice-core data. This is probably due to the higher austral summer and fall temperatures, as shown by Mg/Ca to be on average∼ 4° C higher than during the cooler spring season, accounting for an increase in pCO 2 of∼ 4% per 1° C. Our results demonstrate that paleo-pH estimates based on δ 11 B Cc contain a significant seasonal signal reflecting the habitat preference of the recording foraminifera species.
登录
查看更多内容
DOI：
10.1016/j.dsr2.2008.12.009
发表时间：
2009-04-01
影响因子：
3
作者：
Takahashi, Taro;Sutherland, Stewart C.;de Baar, Hein J. W.
通讯作者：
de Baar, Hein J. W.
共生浮游有孔虫 Orbulina universa 的光合作用及其对海洋初级生产力的潜在贡献
影响因子：
1.1
作者：
H. Spero;S. L. Parker
通讯作者：
S. L. Parker
南大西洋晚第四纪深水环流：碳酸盐溶解和底栖稳定同位素重建
影响因子：
4.9
作者：
T. Bickert;G. Wefer
通讯作者：
G. Wefer
有孔虫种群动态和稳定碳同位素
影响因子：
56.9
作者：
C. Hemleben;J. Bijma
通讯作者：
J. Bijma
影响因子：
3.5
作者：
Foster, G. L.;Pogge von Strandmann, P. A. E.;Rae, J. W. B.
通讯作者：
Rae, J. W. B.