Ocean acidification and surface water carbonate production across the Paleocene-Eocene thermal maximum
Ocean acidification and surface water carbonate production across the Paleocene-Eocene thermal maximum
复制标题
DOI：
10.1016/j.epsl.2010.04.044
复制
发表时间：
2010-07-01
影响因子：
5.3
通讯作者：
Bralower, Timothy J.
中科院分区：
文献类型：
--
作者：
Gibbs, Samantha J.;Stoll, Heather M.;Bralower, Timothy J.
在古新世-始新世最热期（PETM，类似于 55 Ma）向海洋-大气系统中添加大量碳导致了深海酸化，海底碳酸盐沉积物的广泛溶解就证明了这一点。由于这种溶解对碳酸钙保存记录的强烈影响，很难评估地表水化学的变化是否同时影响碳酸盐的产生。在这里，我们通过测试一种将钙质微浮游生物化石计数与分类群特异性 Sr/Ca 数据（颗石藻生产指标）相结合的方法来研究地表水中生物碳酸盐的产生。海洋钻探计划 (ODP) 站点 690（南大洋）、1209（太平洋）和巴斯河（新泽西）重建的超小型浮游生物生产在 PETM 期间似乎没有显着变化，这表明在地质时间尺度上，没有证据表明浮游植物碳酸盐生产中断，尽管与该区间相关的主要组合变化。地表水中的碳酸盐化学变化水平相对较低，可能是二氧化碳排放率的函数，或者与其他环境参数（即温度和养分有效性）的响应相比，钙质纳米浮游生物对这些变化相对不敏感。 (C) 2010 爱思唯尔 BM。版权所有。
The addition of massive amounts of carbon to the ocean-atmosphere system at the Paleocene-Eocene thermal maximum (PETM, similar to 55 Ma) caused deep-ocean acidification, evidenced by widespread dissolution of sea floor carbonate sediments. Because of the strong effect of this dissolution on the preserved record of calcium carbonate it has been difficult to evaluate whether changes in surface water chemistry affected carbonate production at the same time. Here, we investigate the production of biogenic carbonate in surface waters by testing a method which combines fossil calcareous nannoplankton counts with taxon-specific Sr/Ca data, an indicator of coccolithophore production. Reconstructed nannoplankton production at Ocean Drilling Program (ODP) Sites 690 (Southern Ocean), 1209 (Pacific Ocean) and Bass River (New Jersey) did not appear to vary significantly across the PETM indicating that on geological timescales there is no evidence for interruption of phytoplankton carbonate production, despite the major assemblage shifts associated with this interval. Either levels of carbonate chemistry change in surface waters were relatively low, perhaps a function of CO2 emission rates, or calcareous nannoplankton were relatively insensitive to these changes compared with their response to other environmental parameters, namely temperature and nutrient availability. (C) 2010 Elsevier BM. All rights reserved.