Figure 4.

Taxonomic representation of source and mesocosm column sand samples, assigned from the 16S rRNA gene sequencing data. Genera (and un-resolved genera) composing ≥1% of the community at any time (day 0, 6, or 13) within any mesocosm (average of the 2 experimental columns) spiked with PAHs are represented. Source represents the population determined from the field sand sample, prior to manipulation of the sand for the mesocosm experiments. Day 0 represents approximately 6 h during the assembly of the mesocosm experiments in which the bulk of the sand samples were mixed with PAH containing sand mixture. A genus was considered only if it constituted ≥0.01% of the community from any single sample.