Fig 1.

Chloroflexi and Cyanobacteria are the two most abundant phototrophic phyla – their abundance varies with temperature. The natural log of the relative abundance of Cyanobacteria and Chloroflexi for each site is plotted at the phylum level. Each panel represents one phylum.

Biomass was collected from seven Rabbit Creek (RC) sites and three Bison Pool (BP) sites in June 2018. Samples (n = 3 for each site) were collected using flame‐sterilized spatulas or forceps, placed in sterile 2.0‐ml vials and immediately frozen on dry ice and stored at −80°C until nucleic acid extraction. Total DNA was extracted from ∼250‐mg samples using a DNeasy PowerSoil kit (Qiagen, Carlsbad, CA, USA) according to the manufacture's instructions. Amplicons were sequenced using MiSeq Illumina 2 × 300‐bp chemistry at the University of Minnesota Genomics Center (UMGC). We targeted the V4 hypervariable region of bacterial and archaeal 16S small subunit rRNA gene using the modified primers 515F and 806R (Gohl et al., 2016). Postsequence processing was performed using mothur version 1.37.6 (Schloss et al. 2009) following the MiSeq SOP with the following modifications: sequences were classified at a 99% cutoff using the Silva database (v132) and remove. rare was used to remove sequences with less than three reads. Sequence data was analysed using R version 3.6.1 (R Core Team, 2018) and the ggplot2 and tidyverse package (Wickham, 2014, 2016).