秸秆-牛粪发酵过程中溶解性有机质的荧光光谱特征

溶解性有机质(DOM)在自然生态系统有机物向无机物的转换过程中起重要作用。DOM在发酵过程中为微生物提供营养和能量，同时对腐殖质的迁移和转化具有重要的指示作用。牛粪有助于提高玉米秸秆腐殖化效率，使农业废弃物得以更好的利用。为探讨玉米秸秆-牛粪体积比2∶8(T1)、4∶6(T2)、6∶4(T3)和8∶2(T4)处理发酵过程中DOM的特征，采用三维荧光光谱-平行因子分析法，分析发酵底物中DOM的荧光组分；通过荧光指数(FI)和自生源指数(BIX)来表征DOM的来源，用腐殖化指数(HIX)分析发酵物料的腐殖化程度，并分析DOM各组分间最大荧光强度的相关性。结果表明：4个处理过程中DOM来源受自生源和外生源的共同影响(FI>1.4，0.8类富里酸>类胡敏酸。类富里酸和类胡敏酸之间呈现极显著正相关。基于此，根据DOM荧光光谱特性，为提高玉米秸秆在有机物料发酵中的利用率，秸秆-牛粪体积比为6∶4可作为实际堆肥的参考值。

Fluorescence Spectroscopy Characteristics of Dissolved Organic Matter Analysis of Straw-Cow Dung Fermentation in Different Proportion

Dissolved organic matter (DOM) plays an important role in transforming organic matter into inorganic matter in the natural ecosystem. DOM can provide nutrition and energy for microorganisms and has an important role in indicating the transfer and transformation of humus. Cow dung can improve the humification efficiency of corn straw, which makes better use of agricultural waste. In order to study the characteristics of DOM in the fermentation process of corn straw-cow dung, which were treated with 2∶8 (T1), 4∶6 (T2), 6∶4 (T3) and 8∶2 (T4), we adopted three dimensional fluorescence spectrum - parallel factor analysis method to analyze the fluorescence components of DOM in the fermentation substrate. Fluorescence index (FI) and biological index (BIX) were used to analyze the source of DOM; humification index (HIX) was used to characterize the humification degree of fermentation, and the correlation among the maximum fluorescence intensity of DOM components was analyzed. The results showed that the sources of DOM were influenced by both autochthonous and allochthonous sources (FI>1.4, 0.8fulvic-like acid>humic-like acid. There was a significant positive correlation between fulvic-like acid and humic-like acid. Based on these, according to the DOM fluorescence spectroscopy characteristics, to improve the utilization rate of straw in the fermentation process, the ratio of straw and cow dung is 6∶4, which can be used as the reference value of actual composting.