National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology;
Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering;
Beijing University of Technology;
Beijing 100124;
China;
Shuifa Shandong Water Development Group Co.Ltd.;
Shandong 274200;
China;
Partial nitritation; Fulvic acid; Microbial community; Functional genes; Metagenomic;