We investigated the living (stained) and dead benthic foraminiferal assemblages collected in surface sediment samples (0–1 cm) from two different areas (JOIDES Basin and Mawson Bank) of the Ross Sea (Antarctica). Samples were collected during the BEDROSE oceanographic cruise from January to February 2017. Four living and dead benthic foraminiferal fauna assemblages have been distinguished based on cluster analysis. The differences observed in the living and dead foraminiferal content from the two investigated areas are the result of taphonomic processes induced by the different oceanographic settings and environmental conditions. In the JOIDES Basin, agglutinated taxa Rhabdamminella cylindrica, Lagenammina difflugiformis, Adercotryma glomeratum, Recurvoides contortus, Reophax subfusiformis with high percentages of Trochammina group and Reophax spiculifer associated with the calcareous species Nonionella bradii and Astrononion echolsi characterize the living assemblages. The comparison between living and dead benthic foraminifera reveals considerable similarities in terms of the presence/absence of agglutinated species and differences in relative abundance of calcareous taxa. However, the major influencing factor in foraminiferal preservation appears to be the carbonate dissolution. Results from Mawson Bank show an almost exclusive presence of calcareous taxa with high percentages of Globocassidulina group in both living and dead assemblages. The dead fauna assemblage differs from the corresponding living assemblage by being more diverse documenting high-energy current influence on marine sedimentation.

Graphic abstract

我们调查了从罗斯海（南极洲）两个不同地区（JOIDES盆地和莫森河岸）的表面沉积物样本（0-1厘米）中收集的活（有色）底栖有孔虫组合。在2017年1月至2017年2月的BEDROSE海洋航行期间收集了样本。基于聚类分析，已区分出四个有生命的和有生命的底栖有孔虫动物群落。从两个调查区域观察到的有孔有孔虫和死有孔虫含量的差异是由于不同的海洋学环境和环境条件引起的自发过程的结果。在JOIDES盆地中，凝集的类群为Rhabdamminella cylindrica，弥散的Lagenammina，gloderatum的Adercotryma，疏松的Contortus，Reophax subfusiformis具有高比例的Trochammina组和Reophax spiculifer与钙质物种Nonionella bradii和Astrononion echolsi相关的特征是活体组合。活底栖有孔虫和死底栖有孔虫之间的比较显示，在存在/不存在凝集物种和钙质类群相对丰度方面存在相当大的相似性。但是，有孔虫保存的主要影响因素似乎是碳酸盐的溶解。莫森银行（Mawson Bank）的结果显示，钙质类群几乎是唯一的，而球果糖苷的比例很高既有活人也有死人的组合。死动物群与相应的动物群的不同之处在于，它们记录了高能流对海洋沉积的影响，因此更加多样化。

图形摘要