Positive influences of the compost made from distillers’ grains waste on maize agronomic performances and greenhouse gas emissions

To integrate the harmless treatment and resource utilization of piled distillers’ grains waste (DGW) is a great challenge. Thus, the DGW was industrially composted, and a three-year field experiment was conducted to investigate the agronomic and environmental performances of the compost in maize cultivation. It was well composted to organic fertilizer (OF) within 42 days by the addition of lime, microbial starter, and adjuvant with ventilation and pile-turning. Compared with synthesized fertilizer application (SF), SF+OF increased maize yield, N uptake, utilization efficiency, and economic benefits. OF slowly released N in the early growing stage, which synchronized less N uptake by the young maize seedlings and thus significantly reduced inorganic N (NH4+-N and NO3–-N) levels in the soil. SF behaved oppositely, increasing NH3 and N2O emissions. Total CO2 emissions from the soils varied little between SF and SF+OF, and CH4 emission was very low in all treatments. These results suggested more organic matter depletion in the soil fertilized with only SF than that with SF+OF, and CH4 emission could be overlooked in the maize field. Moreover, SF+OF greatly decreased the emissions of NH3 and greenhouse gases for producing each unit of maize grains, showing better agronomic and environmental performances.