Method for improving soil nitrogen retention

The invention belongs to the technical field of sewage treatment, and particularly relates to a method for improving soil nitrogen retention, actinomycetes are adopted for treatment, the actinomycetes strain is a strain Streptomyces mediolani EM-B2, and the preservation number is CCTCC NO: M 2024551. The actinomycete strain EM-B2 shows broad-spectrum environmental adaptability and can efficiently dissimilate nitrate and nitrite to produce ammonium through reduction under the aerobic condition, and the generation rates of NH4 < + > are up to 80.24% and 74.47% respectively; ammonium can be efficiently produced under the condition of mixed nitrogen sources of nitrate and nitrite with various proportional concentrations, the ammonium production effect is better than that of a single nitrogen source, high-concentration nitrate can be tolerated, ammonium is produced through dissimilatory reduction, the actual application range is wider, and the method has good application prospects in the aspect of DNRA and the asp