Study on the Ecological Succession of Microbial Communities During Hot Composting of Livestock Manure

There have been various environmental issues in the treatment and resource utilisation of solid waste of livestock and poultry industry in Gansu Province. Thus, in this study, manure of cattle, pig, and chicken from farms near the Lanzhou University of Technology in Lanzhou City, Gansu Province were selected as raw materials for composting using 10 % corn stalk as a leavening agent for aerobic static composting. This study focused on bacterial, fungal, and actinomycetes community succession during livestock manure composting and the underlying microbial degradation mechanism. The results demonstrated that during livestock manure composting, the number of the above-mentioned types of microbes was all positively correlated with the temperature of the compost piles. In the initial stage of composting, the number of microbes increased as the temperature increased, and reached the peaks at the highest temperature, after which, their numbers decreased with the decrease in temperature. At the end of composting, in the cattle, pig, and chicken manure compost piles, the number of bacteria were respectively (3.1 ±1.0) · 10⁹ CFU·g⁻¹ d.w., (4.4 ±1.0) · 10⁹ CFU·g⁻¹ d.w. and (6.7 ±1.8) · 10⁹ CFU·g⁻¹ d.w., respectively, those of fungi were (8.6 ±1.2) · 10⁴ CFU·g⁻¹ d.w., (7.2 ±1.6) · 10⁴ CFU·g⁻¹ d.w. and (8.0 ±2.8) · 10⁴ CFU·g⁻¹ d.w., respectively, while those of actinomycetes were (8.8 ±2.2) · 106 CFU·g⁻¹ d.w., (9.5 ±2.1) · 106 CFU·g⁻¹ d.w. and (6.32 ±0.98) · 106 CFU·g⁻¹ d.w., respectively.