Salinity is the major driver of the global eukaryotic community structure in fish-canning wastewater treatment plants

Fish-canning wastewater is characterized frequently by a high content of salt (NaCl), making its treatment particularly difficult; however, the knowledge effect NaCl on eukaryotic communities very limited. In present study, global diversity eukaryotes in activated sludges (AS) from 4 different plants (WWTPs) treating fish-canning effluents varying salinity (0.47, 1.36, 1.72 and 12.76 g NaCl/L) was determined sequencing partial 18S rRNA genes using Illumina MiSeq. A greater than previously reported observed AS community, which comprised 37 330 phylum-like genera-like groups, respectively. this sense, more abundant genus-like groups (average relative abundance (RA) > 5%) were Adineta (6.80%), Lecane (16.80%), Dictyostelium (7.36%), Unclassified_Fungi7 (6.94%), Procryptobia (5.13) Oocystis (5.07%). The shared common core 25 clades (95% total sequences); therefore, narrow selection populations found, despite differences abiotic characteristics reactor operational conditions inflicted. concentration main factor that influenced structure modulating RAs core. Higher levels increased Ascomycota, Chlorophyta, Choanoflagellata, Cryptophyta, Mollusca, Nematoda, Other Protists Unclassified Fungi. Among genera here RA (Chlorophyta) intimately correlated to increasing concentrations it proposed as bioindicator community WWTPs.