Ecological response to collapse of the biological pump following the mass extinction at the Cretaceous–Paleogene boundary
Ecological response to collapse of the biological pump following the mass extinction at the Cretaceous–Paleogene boundary
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DOI：
10.5194/bg-14-885-2017
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发表时间：
2016-08
期刊：
影响因子：
4.9
通讯作者：
J. Vellekoop;Lineke Woelders;S. Açikalin;J. Smit;B. Schootbrugge;İ. Yılmaz;H. Brinkhuis;R. Speijer
中科院分区：
文献类型：
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作者：
J. Vellekoop;Lineke Woelders;S. Açikalin;J. Smit;B. Schootbrugge;İ. Yılmaz;H. Brinkhuis;R. Speijer
抽象的。人们普遍认为，与白垩纪-古近纪（K-Pg）界线（距今66 Ma）相关的大规模灭绝与大规模地外撞击的环境效应有关。然而，对大规模灭绝的生物和海洋学后果仍然知之甚少。根据海洋生物模型，K-Pg边界的生物危机导致了古新世早期出口生产力的长期下降。在这里，我们结合联合收割机的有机壁甲藻孢囊（甲藻囊）和底栖有孔虫的分析，提供新的见解变化的耦合的远洋和底栖生态系统。为此，我们最近发现的特提斯K-Pg边界部分Okcular，土耳其，进行dinocyst和底栖有孔虫分析，并与其他K-Pg边界网站的特提斯的结果进行比较。后影响优势的epibenthic morphotypes和增加的推断异养dinocysts在古新世早期在Okcular与其他西特提斯遗址公布的记录是一致的。总之，这些记录表明，在古新世早期，更多的营养物质仍然可用于特提斯南极群落，而底栖群落被剥夺了食物。因此，在影响后阶段，出口生产力的降低可能导致水柱上部营养物的循环增强，所有沿着西特提斯边缘。
Abstract. It is commonly accepted that the mass extinction associated with the Cretaceous–Paleogene (K–Pg) boundary (∼ 66 Ma) is related to the environmental effects of a large extraterrestrial impact. The biological and oceanographic consequences of the mass extinction are, however, still poorly understood. According to the Living Ocean model, the biological crisis at the K–Pg boundary resulted in a long-term reduction of export productivity in the early Paleocene. Here, we combine organic-walled dinoflagellate cyst (dinocyst) and benthic foraminiferal analyses to provide new insights into changes in the coupling of pelagic and benthic ecosystems. To this end, we perform dinocyst and benthic foraminiferal analyses on the recently discovered Tethyan K–Pg boundary section at Okcular, Turkey, and compare the results with other K–Pg boundary sites in the Tethys. The post-impact dominance of epibenthic morphotypes and an increase of inferred heterotrophic dinocysts in the early Paleocene at Okcular are consistent with published records from other western Tethyan sites. Together, these records indicate that during the early Paleocene more nutrients remained available for the Tethyan planktonic community, whereas benthic communities were deprived of food. Hence, in the post-impact phase the reduction of export productivity likely resulted in enhanced recycling of nutrients in the upper part of the water column, all along the western Tethyan margins.