title: 18S amplicon sea ice
design: DNA was extracted directly from the filter, following the power soil pro kit protocol (Qiagen), including a DNA extraction negative control. 18S rRNA gene copies were quantified using primers Euk345F (5- AAGGAAGGCAGCAGGCG-3) and Euk499R (5- CACCAGACTTGCCCTCYAAT-3) Golden, K. M., Eicken, H., Heaton, A. L., Miner, J., Pringle, D. J., Zhu, J. 2007. Thermal evolution of permeability and microstructure in sea ice. Geophysical Research Letters, 34. https://doi.org/10.1029/2007GL030447.