Modern distribution of benthic foraminifera on the north Icelandic shelf and slope

Forty-six surface samples from the north Icelandic shelf and slope were analyzed with respect to both living (stained) and total (living/stained + dead/unstained) benthic foraminiferal faunas. Near-coastal samples are strongly dominated by species indicating a high-energy environment, among these various species of the genus Cibicides. Nonionellina labradorica, which has a strong affinity to areas of high surface primary production, is constrained to oceanic boundaries on the outer shelf. Faunistically, the area is further divided into eastern and western parts, the submarine Kolbeinsey Ridge forming a barrier. Calcareous species, particularly Melonis barleeanus, prevail in the western part, while the assemblages in the eastern part are strongly dominated by agglutinated foraminifera. Principal Component Analyses (PCA) help distinguish four main components of both the total (living + dead) assemblage (TA) and the total living assemblage (TLA), as well as of the total (living + dead) calcareous assemblage (CA) and the living calcareous assemblage (CLA). The components of the TA and TLA are similar, the major differences being controlled by species-dependent variables such as adaptability to changes in food supply and, in the eastern part of the area, depth of microhabitat and possibly a limited primary production. The PCA analyses of the calcareous species alone (CA and CLA) define components with significant differences in the foraminiferal population. The calcareous distribution in particular is important in application of modern distribution patterns to paleoceanographical and paleoclimatological reconstructions in areas where post-mortem disintegration of the agglutinated fauna may have occurred.