Spectral characteristics changes as affected by inoculating microbial agents during composting

xiayan liu; Lingyu Kong; Rongsheng Zhu; Zhaojun Li; yizhong Lv

Just Accepted

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Spectral characteristics changes as affected by inoculating microbial agents during composting

xiayan liu, Lingyu Kong, Rongsheng Zhu, Zhaojun Li , yizhong Lv

Abstract

Context. Microbial inoculations have become a key strategy to overcome the limitations of traditional composting (such as low microbial activity and degradation efficiency of organic matter), attracting significant research interest. Aims. This study aimed to explore the effect of microbial inoculation on on the spectral characteristics of the organic matter transformation during primary and secondary fermentations. Methods. Aerobic composting was carried out for 39 days and compost samples at different stages were analyzed by UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). Key results. The findings revealed that the humification and high polymerization of compost organic matter mainly occurred during primary fermentation and the early secondary fermentation, while humification degree decreased in the late secondary fermentation. Microbial inoculation facilitated the oxidative decomposition of fatty chains attached to benzene rings in organic matter during the early stage of secondary fermentation, lesding to the formation of functional groups such as carbony1, carboxyl, and hydroxyl, which promoted the transformation of compost organic matter into humus. As composting progressed, carbohydrates, proteins, lignin, and aliphatic compounds gradually decomposed, with an increase in aromatic substances containing carbonate-containing aromatic rings. Microbial inoculation enhanced complete decomposition of carbohydrates, aliphatic compounds and lignin, thus promoting the transformation of humus in the early secondary fermentation. Microbial inoculation effectively facilitated cellulose-like polysaccharide degradation during composting. Conclusions. Microbial inoculum promote the transformation of humus in compost by affecting physical and chemical factors. Implications. This study can provide theoretical guidance for optimizing composting conditions, improving composting quality and soil fertility.

SR24189 Accepted 25 March 2025