Figures
Figure 1. Map of the stations in the LTER HAUSGARTEN at the West Spitsbergen Current in the Fram Strait. The sediment traps used in this study were deployed at station HG-IV.
Figure 2. Summary of the different community profiles collected from the sediments traps and generated using different primer sets but the same mock community.
Figure 3. The summer and spring eukaryotic microbial communities collected from the sediment traps deployed at 200 to 300 m in HAUSGARTEN, Fram Strait, from 2000-2011, and amplified using the Stoeck, Wolf938 and Wolf964 primer sets.
Figure 4. Results of the EPA-RAxML placement of the OTUs generated by the Stoeck, Wolf938 and Wolf964 primer sets back onto the reference trees for (A) chlorophytes, (B) haptophytes, and (C) diatoms. The black circles correspond to the placement of the OTUs in the tree, the size represent the number of OTUs placed in a particular node relative to each primer dataset for each species.
Figure 5 . Dominant OTUs exhibited alternating patterns before, during and after the warm anomaly years 2005-2007 in both spring and summer periods, including the (A, C) Micromonas OTUs 2 and 268, which represent warm-adapted (Clade C) and cold-adapted (Clade Ea), and (B, D) the warm-associated Emiliania and Arctic residentPhaeocystis from the haptophyte group.
Supplementary Figure 1S . Result of the in silico test to evaluate the sensitivity of the different primer sets to the major phytoplankton groups in the Arctic including the chlorophytes, haptophytes, dinoflagellates and diatoms.
Supplementary Table S1. Summary of the cultures and strains used to generate the mock community that was used to evaluate the biases and limitations of the primer sets.