蜉金龟堆肥施入后土壤腐殖质表征及特性研究

采用元素组成、红外光谱及差热分析对土壤施用蜉金龟堆肥后腐殖质结构特征的变化进行表征。元素分析结果表明,与对照处理相比,土壤施用蜉金龟堆肥后焦磷酸钠浸提胡敏酸(NaHA)、氢氧化钠浸提胡敏酸(PAHA)、焦磷酸钠浸提富里酸(NaFA)及氢氧化钠浸提富里酸(PAFA)的碳含量增加,H/C减小,表明施肥后土壤腐植酸(胡敏酸和富里酸)的芳香性增加。差热分析结果表明,与NaHA相比,对照处理和施蜉金龟堆肥PAHA的高温放热峰消失,说明PAHA的热稳定性低于NaHA;而NaFA在两种处理中的中温反应热也均高于PAFA,进一步说明了氢氧化钠浸提腐植酸的热稳定性高于焦磷酸钠浸提的腐植酸。红外光谱结果表明,两种提取剂提取的土壤腐植酸均含有大量的芳香化合物和碳水化合物。综上,两种提取剂对土壤腐植酸在热性质及官能团的组成上存在着差异性。

Characteristics of Humic Substances of Soil Applied with Aphodius-processed Cow-manure

The structural features of humic substances were characterized using elemental analysis, infrared spectrometry and thermal analysis techniques. Elemental analysis showed that it was lower and higher aromaticity that carbon content of Na4P2O7-extracted humic acid (NaHA), NaOH-extracted humic acid (PAHA), Na4P2O7-extracted fulvic acid (NaFA) and NaOH- extracted fulvic acid (PAFA) in application vermi-compost compared with control treatment. Thermal analysis suggested that high temperature exothermic peak of PAHA disappeared in application vermi-compost and control treatment compared with NaHA. NaHA had larger thermal stability and mid-temperature exotherm than PAHA. Infrared spectrometry suggested that soil humus from Na4P2O7-extracted and NaOH-extracted humus included a large number of aromatic compounds and aliphatic compounds. In summary, some differences between Na4P2O7-extracted humus and NaOH-extracted humus existed in thermal properties and composition of functional groups.