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

ABSTRACT

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.

KEYWORDS:

• Distillers’ grains waste
• organic fertilizer
• crop cultivation
• greenhouse gas
• circular economy

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data that support the findings of this study are available from the corresponding authors upon request.

Additional information

Funding

This work was supported by the the Scientific Innovation Project for Postgraduates, Chongqing, P. R. China [CYB20097]; Zunyi Company of Guizhou Provincial Tobacco corporation, Guizhou, P. R. China [2020XM03].