The
key limiting factors in the treatment of low C/N micropolluted
water bodies are deficient essential electron donors for nitrogen
removal processes. An iron/activated carbon aquagel (IACA) was synthesized
as a slowly released inorganic electron donor to enhance aerobic denitrification
performance in low C/N micropolluted water treatment. The denitrification
efficiency in IACA reactors was enhanced by more than 56.72% and the
highest of 94.12% was accomplished compared with those of the control
reactors. Moreover, the CODMn removal efficiency improved
by more than 34.32% in IACA reactors. The Illumina MiSeq sequencing
consequence explained that the denitrifying bacteria with facultative
denitrification, iron oxidation, and iron reduction function were
located in the dominant species niches in the IACA reactors (e.g., Pseudomonas, Leptothrix, and Comamonas). The diversity and
richness of the denitrifying bacterial communities were enhanced in
the IACA reactors. Network analysis indicated that aerobic denitrifying
bacterial consortia in IACA reactors presented a more complicated
co-occurrence structure. The IACA reactors presented the potential
for long-term denitrification operation. This study affords a pathway
to utilize IACA, promoting aerobic denitrification during low C/N
micropolluted water body treatment.