Study on the promotion of composting process of cow dung aerobic composting by biochar-based microbial agents

Abstract

In order to evaluate the effect of biochar-based microbial agent on promoting the maturity of aerobic composting of cow dung, a composting experiment was conducted with cow dung as raw material and self-made biochar-based microbial agent for 34 days, and the changes of physical and chemical indexes and microbial communities during composting were studied with pure cow drug as blank control. The results show that after adding biochar-based microbial agents, the composting temperature could reach 53 ℃ within 1 day, and the highest composting temperature is 717 ℃, which is 46 ℃ higher than that of the control group, and the high temperature period is prolonged for 3 days. By the end of composting, the moisture content, E4/E6 and GI of treatment group and control group are 29% and 33%, 15 and 19, 1455% and 1276%, respectively. Through the correlation analysis, it is found that the correlation value of accumulated temperature, moisture content, pH value and other physiochemical indicators increases by 67%, and the correlation value with bacterial phylum level increases by 56%. Therefore, the addition of 01%(w/w) biochar-based microbial agent could accelerate the decomposition process, improve microbial diversity, accelerate the succession of microbial communities and the catabolism of materials, and promote the compost maturity process, which provides theoretical basis for the application of biochar-based microbial agents in aerobic composting.

Keywords

• applied microbiology; biochar-based microbial agent; aerobic composting; cow dung; maturity; bacterial communities