Fig 4.

Absolute cell numbers calculated from total cell numbers (Fig. 2) and abundances retrieved in triplicate from CARD FISH analyses of 3 independent filters. For simplification, error bars show the standard errors of the CARD FISH triplicates. Absolute cell numbers of IN (black, straight lines) and OUT (white, dotted lines) stations are shown for SAR11 (A), Roseobacter (B), the Roseobacter subgroup clades OCT (C) and DC5-80-3 (D), Bacteroidetes (E) and the subgroup Polaribacter (F), and Gammaproteobacteria (G) with the subgroup SAR86 (H). We used a different scale for the SAR11 clade numbers. The days of iron fertilization events are marked with asterisks. t, time.