沼渣堆肥过程中水溶性有机物的稳定化研究

Study on dissolved organic matter stabilization during biogas residue composting

设计了不同原料配比的沼渣堆肥试验,研究堆肥微生境因子对沼渣堆肥过程中水溶性有机物(DOM)稳定化的影响。结果表明,沼渣堆肥过程中,原料配比不同导致堆肥理化性质不同,细菌群落多样性各异。沼渣为5.85 kg、猪粪为8.490 kg、鸡粪为8.190 kg的原料配比最有利于沼渣堆肥的DOM稳定化。用DOM的光谱学指标表征的稳定化程度,总体与微生境因子pH、种子发芽指数(GI)、香农指数(SWI)具有正相关性,与微生境因子氨氮(AN)具有负相关性,其中GI对DOM光谱学指标方差贡献率最大,是影响DOM稳定化的关键微生境因子。pH、AN通过影响GI间接作用于DOM稳定化。SWI在堆肥过程中对芳香族化合物含量升高具有促进作用。综上所述,升高pH、GI、SWI,降低AN可加速腐殖质向腐殖酸转化,达到促进沼渣堆肥稳定化的目的。

Different material components of biogas residue composting experiments were designed.The effect of microhabitat factors on dissolved organic matter(DOM)stablization was studied.Results showed that different material components led to different chemical and physical properties of the compost,and the bacterial community abundance was also different.When biogas residue was 5.85 kg,pig manure was 8.490 kg,and chichen manure was 8.190 kg,it was most helpful for DOM stabilization in composting process.When DOM spectroscopic indexes were used to represent DOM stabilization,it was found that microhabitat factors pH,seed germination index(GI)and Shannon index(SWI)were positively correlated with DOM spectroscopic indexes in general,while ammonia nitrogen(AN)was negatively correlated.Among them,GI had the largest contribution to the variance of DOM spectroscopic indexes,as the key microhabitat factor.pH and AN indirectly affected DOM stabilization by affecting GI.SWI could promote the content of aromatic compounds in the composting process.To sum up,increasing pH,GI and SWI,or reducing AN could accelerate the transformation of humus to humic acid,thus promoting the biogas residue composting stabilization.