Application of highly efficient microbial agent in pig manure compost.

[Objective] The aim of this study was to develop a cheap and localized microbial agent so as to solve high cost of microbial agent for pig manure composting in Jiaxing City. [Method] Pig manure in the experimental group and control group was inoculated with the self-developed microbial agent and commercial microbial agent, respectively. The manure was decomposed for 38 d, during which the indicators of compost including physical properties, temperature, pH value, water content, organic matter, dissolved nitrogen, carbon nitrogen ratio and germination rate were studied. [Result] The water content in the experimental group declined to 26.10% after 33 d of compost, meeting the standard upper limitation of 30% for maturity. By comparison, the water content in the control group was slightly higher than 30% even after 38 d. The germination rate of seeds fertilized with the experimental manure compost met the standard for maturity on Day 28, while that in the control group met the standard for maturity on Day 35. When the composting was finished, the ratio of total carbon to total nitrogen in the pig manure was 14.64 and 16.43 respectively in the experimental and control group, and the organic matter content was about 45% for both. All these indexes could meet the standards for organic fertilizer products. [Conclusion] The self-developed microbial agent can meet the requirements for pig manure composting, and it can shorten the composting time by 5-8 d compared with the commercial agent. In addition, the fertilizer product composted by the self-developed microbial agent has lower water content and thereby is much more beneficial for preservation.