分阶段接菌对中药残渣堆肥腐熟度及微生物多样性的影响

Effect of Multi-Stage Inoculation on Maturity and Microbial Diversity during Chinese Medicinal Herbal Residue Composting

堆肥通常用于处理有机固体废弃物,可通过接种木质纤维素降解功能菌群提高堆肥进程及产品品质.然而,堆肥过程中传统的功能菌群一次性添加方式,不仅造成了堆肥过程中较低的堆肥效率,而且堆肥产品品质也并不稳定.为了探究基于不同接种方法对堆肥过程腐熟度和品质的影响,设置M0(不接菌)、M1(分阶段接菌)及M2(一次性接菌)3个好氧堆肥处理,考察各处理堆肥过程中理化性质变化、木质纤维素降解及微生物群落多样性.结果表明:M1处理下,堆肥至第20天,堆体温度达到51.2℃且拥有最高的嗜热温度(67.8℃);堆肥至第67天,发芽指数达到83.61%.此外,M1处理下腐殖质增长率、总有机碳降解率、纤维素降解率和木质素降解率均最高,分别为50.20%、53.86%、59.87%和40.61%,远高于其他2个处理.变性梯度凝胶电泳(DGGE)分析显示,在嗜热期,真菌种群对于木质纤维素生物降解的作用比细菌种群更加突出,并且受到总磷含量、pH、碱解氮含量和碳氮比的显著影响.研究显示,分阶段接菌可以显著提高堆体温度及堆体中木质纤维素降解酶活性,促进堆体腐熟进程及堆肥产品中腐殖质等养分积累.

Composting is usually used to treat organic solid waste.The composting process and product quality can be improved by inoculating lignocellulose-degrading functional consortium.However,the traditional single-stage inoculating method of functional consortium in the composting process not only reduces composting efficiency,but also causes the unstable quality of compost product.In this study,the effect of different inoculation methods on composting maturity and quality during composting were investigated.Three aerobic composting treatments were set up,including:no inoculation in the whole composting process(M0),multi-stage inoculation(M1),and single-stage inoculation(M2).The physicochemical parameters,lignocellulose degradation,and microbial community diversity were determined during composting.The results showed that the composting temperature of M1 reached 51.2℃on the 20 th day of the experiment with the highest thermophilic temperature up to 67.8℃,and the germination index(GI)of this treatment was 83.61%on the 67 th day.Moreover,the increase in humic substances and the degradation of total organic carbon,cellulose and lignin in composting treatment M1 were significantly higher than the other two composting treatments,reaching up to 50.20%,53.86%,59.87%and 40.61%,respectively.The results of DGGE showed that compared with the bacterial community in the thermophilic stage,fungal community which was significantly affected by total phosphorus,pH,available nitrogen,and carbon to nitrogen ratio played a more important role in the degradation of lignocellulose.Overall,the results showed that the multi-stage inoculation treatment had the highest thermophilic temperature,increased the activity of lignocellulose degrading enzymes,accelerated the compost maturity process,and improved the accumulation of humus in the compost products.