The impact of the 1991 Mt. Pinatubo eruption on deep-sea foraminiferal communities: A model for the Cretaceous–Tertiary (K/T) boundary?
The impact of the 1991 Mt. Pinatubo eruption on deep-sea foraminiferal communities: A model for the Cretaceous–Tertiary (K/T) boundary?
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DOI：
10.1016/j.palaeo.2005.03.042
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发表时间：
2005-08
期刊：
影响因子：
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通讯作者：
W. Kuhnt;S. Hess;A. Holbourn;Harald Paulsen;Brigitte Salomon
中科院分区：
文献类型：
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作者：
W. Kuhnt;S. Hess;A. Holbourn;Harald Paulsen;Brigitte Salomon
1991 年皮纳图博火山喷发的火山灰层提供了一个天然实验室，用于评估灾难性事件后的大规模死亡率和深海生态系统的恢复速度，并与 K/T 边界事件对深海有孔虫群落的环境影响进行比较。皮纳图博火山灰落后的第一个底栖有孔虫重新定居组合与 K/T 边界事件后建立的底栖有孔虫群落表现出惊人的相似性，即相对较低的丰度和多样性、缺乏悬浮饲养者、移动动物类群占主导地位以及高比例的凝集有孔虫。在两次灾难性事件之后，第一批重新定居深海的有孔虫是具有快速扩散能力的机会主义形式。然而，动物区系转变的时间和持续时间存在明显的主要差异。经过大约 10 年的短暂初始重新定殖阶段后，形成了具有高比例表层悬浮食饵的喷发后组合。皮纳图博山火山灰层上 6-7 年。在 K/T 剖面中，相对稳定的新底栖有孔虫组合，包括悬浮喂食器，直到事件发生几千年后才建立起来。中上层生态系统恢复的延迟和深水通风不良可能减缓了K/T边界后底栖群落结构的恢复。
The ash layer from the 1991 Mt. Pinatubo eruption provided a natural laboratory to assess mass mortality and the rates of recovery of deep marine ecosystems after a catastrophic event and to draw a parallel with the environmental impact of the K/T boundary event on deep-sea foraminiferal communities. The first recolonization assemblages of benthic foraminifers after the Mt. Pinatubo ash fall exhibit surprising similarities with benthic foraminiferal communities established following the K/T boundary event, i.e., comparatively low abundance and diversity, absence of suspension feeders, dominance of mobile infaunal taxa and a high proportion of agglutinated foraminifers. The first foraminifers to recolonize the deep sea after both catastrophic events were opportunistic forms with high capability for rapid dispersal. However, major differences are evident in the timing and duration of the faunal transitions. Post-eruption assemblages with high proportions of epibenthic suspension feeders became established after a short initial recolonization phase of approx. 6–7 years on the Mt. Pinatubo ash layer. In the K/T sections, comparatively stable new benthic foraminiferal assemblages, including suspension feeders, only became established several thousand years after the event. Delayed recovery of the pelagic ecosystem and poor deep-water ventilation probably slowed down the recovery of the benthic community structure after the K/T boundary.