Change *with the sequences rarefied to a depth of 100* to *with exactly 100 sequences per sample* - less jargon-y. Also, describe the motivation for this step: we're doing this to control the runtime of this step, and also to compare all samples based on an even number of sequences, which is known to affect the results of some methods of community comparison. @danknights, did you specifically check whether uneven sampling depth is an issue for SourceTracker?