Abstract:
In order to explore the effects of micro-nano bubble water (MNBW) on compost maturation and the microbial community in cow manure and straw during aerobic composting, we conducted composting tests using tap water with 12 mg/L (O12), 15 mg/L (O15), 18 mg/L (O18), and 21 mg/L (O21) dissolved oxygen in MNBW, as well as tap water with 9 mg/L dissolved oxygen as a control (CK). The results showed that O21 increased the maximum compost temperature to 64 °C, which was higher than the other treatments. All treatments met the harmless standards for compost. The seed germination index (GI) was largest under O21 and 15.1% higher than that under CK, and the non-toxic compost degree was higher. Redundancy analysis showed that the temperature, C/N, pH, and GI were important factors that affected the microbial community composition. The temperature, C/N, and pH were significantly positively correlated with Firmicutes and Actinobacteria (p < 0.05). Firmicutes was the dominant phylum in the mesophilic stage (2-6 days) and it accounted for a large proportion under O21, where the strong thermophilic metabolism increased the production of heat and prolonged the high temperature period. The bacterial genus Ammoniibacillus in Firmicutes accounted for a large proportion under O21 and it accelerated the decomposition of substrates. Therefore, the addition of MNBW changed the microbial community to affect the maturation of the compost, and the quality of the compost was higher under O21.
摘要:
为探讨微纳米气泡水(MNBW)对好氧堆肥过程中堆肥成熟及牛粪和秸秆微生物群落的影响,我们用12mg/L(O12)的自来水进行堆肥试验,15mg/L(O15),18mg/L(O18),MNBW中的溶解氧为21mg/L(O21),以及含9mg/L溶解氧的自来水作为对照(CK)。结果表明,O21将堆肥的最高温度提高到64℃,高于其他治疗。所有处理均符合堆肥的无害标准。O21下种子萌发指数(GI)最大,比CK下种子萌发指数高15.1%,无毒堆肥程度较高。冗余分析表明,温度,C/N,pH值,和GI是影响微生物群落组成的重要因素。温度,C/N,pH值与Firmicutes和放线菌呈显著正相关(p<0.05)。Firmicutes是中温阶段(2-6天)的主要门,在O21下占很大比例,在O21下,强烈的嗜热代谢增加了热量的产生并延长了高温期。在O21下,Firmicutes中的细菌氨芽孢杆菌属占很大比例,它加速了底物的分解。因此,添加MNBW改变了微生物群落,影响堆肥的成熟,O21下堆肥质量较高。