Data_Sheet_1_The Effect of Size Fraction in Analyses of Benthic Foraminiferal Assemblages: A Case Study Comparing Assemblages From the >125 and >150 μm Size Fractions.pdf

<p>Benthic foraminiferal assemblages are employed for past environmental reconstructions, as well as for biomonitoring studies in recent environments. Despite their established status for such applications, and existing protocols for sample treatment, not all studies using benthic Foraminifera employ the same methodology. For instance, there is no broad practical consensus whether to use the >125 or >150 μm size fraction for benthic foraminiferal assemblage analyses. Here, we use early Pleistocene material from the Pefka E section on the Island of Rhodes (Greece), which has been counted in both size fractions, to investigate whether a 25 μm difference in the counted fraction is already sufficient to have an impact on ecological studies. We analyzed the influence of the difference in size fraction on studies of biodiversity as well as multivariate assemblage analyses of the sample material. We found that for both types of studies, the general trends remain the same regardless of the chosen size fraction, but in detail significant differences emerge which are not consistently distributed between samples. Studies which require a high degree of precision can thus not compare results from analyses that used different size fractions, and the inconsistent distribution of differences makes it impossible to develop corrections for this issue. We therefore advocate the consistent use of the >125 μm size fraction for benthic foraminiferal studies in the future.</p

Modern_station_IDs

This file contains the station IDs used in the Reduced_modern_data.txt, their original station IDs, water depth (in m) and station location (Adriatic Sea or Western Mediterranean Sea (Alboran Platform, Oran Bight and Mallorca Shelf)). The data from the Adriatic Sea are from Jorissen (1987, 1988): -Jorissen FJ. The distribution of benthic foraminifera in the Adriatic Sea. Mar Micropaleontol. 1987;12:21-48. doi: 10.1016/0377-8398(87)90012-0. -Jorissen FJ. Benthic foraminifera from the Adriatic Sea: principles of phenotypic variation. Utrecht Micropaleontological Bulletins. 1988;37:1-174

WMed_census_counts

This file contains the complete modern dead benthic foraminiferal census counts (fraction >150 µm), total foraminiferal numbers, sample split, and sample volume from three study areas in the Western Mediterranean Sea (Alboran Platform, Oran Bight and Mallorca Shelf). In the first two columns the station IDs and the water depth (in m) is given

Reduced_Pefka_E_data

This file contains the relative abundance of fossil benthic foraminifera from the Pefka E section used for the application of the transfer function in this study. In the first column the adjusted section depth (in cm) is given

Composition and grain sizes of the end members in core M40/4_SL71.

<p>A: grain size end members, B: clay mineral end members, C: XRF end members.</p

Variation patterns of the grain size end-member loadings in core M40/4_SL71 through time.

<p>Grey shaded areas mark the sapropels, and the ash layers are indicated by the red lines.</p

Results of the end-member modelling of the three datasets from sediment core M40/4_SL71.

<p>(A) grain size dataset, (B) clay mineral dataset, (C) XRF dataset. Left: <i>r</i>² mean = mean coefficients of determination versus the number of end members in each end-member model. Right: <i>r</i>² = coefficient of determination for each variable used in the end-member modelling.</p

Variation patterns of the clay mineral end-member loadings in core M40/4_SL71 through time.

<p>Grey shaded areas mark the sapropels, and the ash layers are indicated by the red lines.</p

Pefka_E_census_counts

This file contains complete fossil benthic foraminiferal census counts (fraction >150 µm), total foraminiferal numbers, sample split, and (modified) plankton to benthos ratios (of the >125µm fraction) from the Pefka E section. In the first column the adjusted section depth (in cm) is given

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