采用红外光谱法探讨了有机肥以及有机肥与化学肥料配合施用26年对棕壤腐殖质及其组分富里酸和胡敏酸的结构变化。 结果表明, 采用红外光谱仪测定肥料施用对腐殖质及腐殖质组分富里酸和胡敏酸结构的影响是可行的。 施肥26年后, 不同处理肥料施用后腐殖质具有基本一致的结构; 在某些特征峰吸收强度上有不同程度的差异, 反映了不同肥料处理对土壤腐殖质的结构单元和官能团数量及组成有明显的影响。 不同施肥处理胡敏酸也存在一些差别。 红外光谱解析表明, 与CK相比, 施用有机肥或氮磷钾配合施用后, 土壤腐殖质中小分子糖类物质减少, 芳族类物质增加。 试验结果证实, 施用有机肥可明显增加土壤水溶性有机物芳构化程度。 利用不同肥料处理腐殖质的红外光谱, 可以判断土壤有机质的演变程度。

The infrared spectrum was used to discuss structure change of soil humus and components of chemical groups in soil humic acids (HA) and fulvic acids (FA) isolated from soils in different fertilization treatment after 26 year’s fertilization. The result indicated that using the infrared spectroscopy method for the determination of humus, humus fractions (HA and FA) and their structure is feasible. Fertilization affected the structure and content of soil humus and aromatization degree. After 26 years’ fertilization, the infrared spectrum shapes with different treatments are similar, but the characteristic peak intensity is obviously different, which reflects the effects of different fertilization treatments on the structure and amounts of soil humus or functional groups. Compared with no fertilization, little molecule saccharides decreased and aryl-groups increased under application of inorganic fertilizer or combined application of organic and chemical fertilizer. The effect was greater in Treatment NPK and M+NPK than in Treatment M1N and M2N. Organic and NPK fertilizer increased the development of soil and increased soil quality to a certain extent. Results showed that organic fertilization increased aromatization degree of soil humus and humus fractions distinctly. The authors could estimate soil humus evolvement of different fertilization with infrared spectroscopy.