Benthic foraminifera in South Atlantic Ocean surface sediments

Benthic foraminiferal assemblages were analyzed on forty-eight surfacesediment samples which were taken with a multiple corer from the southern South Atlantic Ocean and the northern Angola-Basin. The short cores were split into 1-cm-thick slices down to 15 cm sediment depth. Live (with Rose Bengal stained) and dead faunas were counted separately. The data were used to calculate numerical faunal characteristics like standing stocks, benthic foraminifera accumulation rates, diversity, average living depth, and habitat depth. Additionally the live and dead faunas were grouped into a number of principal faunal endmembers by Q-mode principal component analysis. Faunal composition, numerical faunal characteristics, and isotopic composition of calcareous tests were correlated with available environmental variables. Oxygen content in Pore water and rates of primary production were calculated by faunal composition and benthic foraminifera accumulation rate. […]本研究对采自南大西洋南部与安哥拉盆地北部的48个表层沉积物样品开展分析，样品由多管采样器（multiple corer）采集。所获短岩芯被切割至沉积物深度15 cm处，分切为厚度1 cm的样品切片。分别计数经玫瑰红（Rose Bengal）染色的活有孔虫与死亡有孔虫群落。基于上述数据，计算得到多项底栖有孔虫群落数值特征，包括现存量（standing stocks）、底栖有孔虫堆积速率（benthic foraminifera accumulation rates）、物种多样性、平均栖息深度与生境深度。此外，通过Q型主成分分析（Q-mode principal component analysis）将活、死有孔虫群落划分为若干核心群落端元（principal faunal endmembers）。将有孔虫群落组成、群落数值特征以及钙质壳体（calcareous tests）的同位素组成与已获取的环境变量进行相关性分析；并基于有孔虫群落组成与底栖有孔虫堆积速率，计算得到孔隙水含氧含量与初级生产力速率。……