“…In the microbial composition at the genus level (Fig. 6) denitrifying bacteria genera were relatively more abundant in the solar radiation device, such as norank__f__AKYH767 (TY16.19%, HW12.99%, SW17.24%) and unclassi ed__f__Comamonadaceae (TY6.84%, HW3.30%, SW4.02%), while organic matter-degrading functional bacteria such as norank__f__JG30-KF-CM45 (TY2.66%, HW7.63%, SW3.66%), a genus itself belonging to Chloro exi, which is greatly affected by anaerobic and anoxic conditions, dominated the thermostatic room temperature device [41], the degradation of organic matter by this group of genera provided a carbon source for the growth and metabolism of nitrogen-metabolizing functional bacteria, which further enhanced the nitrogen removal capacity.There were fewer species of denitrifying bacteria genera in this study, whereas a variety of denitrifying functional bacteria genera were found to be present in the A 2 O reactor in the study of Yu Z et al [42] The reason for this is that the higher intensity of solar radiation in the plateau can damage the nucleoprotein and DNA of microorganisms, and some microorganisms are inhibited or even eliminated under the selection of strong solar radiation conditions [43,44]. And this inhibitory or destructive effect is extremely signi cant for unclassi ed_f__Saprospiraceae.…”