Benthic foraminifera assemblages in the Central Barents Sea: an evaluation of combining live and total fauna studies in tracking environmental change

Abstract

We present living (stained) benthic foraminifera assemblage data in nine surface sediment samples from the central Barents Sea collected in 2005 and 2006. The abundances of 20 selected species are compared to these from previously published total fauna assemblages of nearby samples. Between 1 and 3 total fauna samples from various years (between 1971 and 1992) are compared with the modern (2005 and ’06) samples. The main purpose of the paper is to evaluate the applicability of this comparison. We conclude that, with proper caution, comparing live and total fauna can yield valuable results. Eliminating fragile species, and clustering species according to environmental preferences strengthens the results. A second purpose of the paper is assessing benthic foraminifera assemblage change in the basin. The data show that foraminiferal assemblage changes vary strongly through the basin, with maximum change in the extreme north and south of the study area. Division of the species into three major faunal groups related to specific environmental conditions shows that the abundance of cold water species decreases in the eastern part of the study area, while the abundance of warm water species increases in most of the western area. A reverse trend is seen in the most central locality.