The Data QC and OTU Clustering workflow consists of 3 tools being executed sequentially (figure 4.26). The only necessary input to run the workflow are the reads you want to cluster. You also have the option to provide a list of the primers that were used to sequence these reads if you wish to perform the adapters trimming step with the Trim Sequences tool.
The first tool is the Trim Reads tool. Together with the sequencing primer list, this tool provides a list of trimmed sequences that will be the input of the Filter Samples Based on Number of Reads tool. The results of the trimming and the filter steps are compiled in two reports. The "filtered" list of reads (devoid of reads of poor quality) will be used for the final tool of the workflow, the OTU clustering tool. This tool will give a report, and an abundance table with the newly created OTUs, their abundance at each site as well as the total abundance for all samples.