不同退化程度与人工恢复方式对草原土壤胡敏酸结构的影响（英文）

发布时间：2018-03-02 13:46

本文选题：胡敏酸　切入点：结构变化　出处：《光谱学与光谱分析》2017年09期 　论文类型：期刊论文

【摘要】：该研究主要探讨不同退化程度和人工恢复方式对草原土壤胡敏酸结构的变化特征,为退化草原恢复提供理论依据。在鄂尔多斯沙地不同退化样地与人工恢复草地,对草原土壤的腐殖酸进行了分离提取,采用元素分析、~(13)核磁共振(NMR)等方法对荒漠草原土壤退化与恢复过程中土壤胡敏酸(HA)不同官能团的含量变化进行分析,并用因子分析法研究它们的结构特征和差异。结果表明:不同退化及恢复阶段HA碳骨架相似,但各类碳原子(官能团)的含量不同,芳香族和脂肪族结构在胡敏酸结构中发挥了重要作用。退化阶段,土壤HA的芳香碳减少,碳水化合物减少,土壤HA的氧化程度增加,疏水程度降低。恢复阶段土壤芳香碳含量增加,碳水化合物含量增加,疏水程度略有降低。土壤退化及恢复阶段,胡敏酸(HA)的结构变化最大的部分是芳香碳、取代脂肪碳结构,其次是羧基和酯基碳和未取代脂肪碳结构。植被恢复对腐殖酸结构的变化有重要的影响,本氏针茅区和本氏针茅+油蒿区的HA结构中芳香化程度和复合程度较高,氧化程度低。围栏样区内土壤胡敏酸(HA)的酸度相对较高,芳香化程度和复合程度仍然较低。因此,土壤胡敏酸结构特征的变化可以反映草原土壤的退化程度,进一步揭示草原土壤退化的机制。
[Abstract]:In this study, the variation characteristics of Hu Min acid structure in grassland soil with different degree of degradation and artificial restoration were studied, which provided theoretical basis for restoration of degraded grassland. Different degraded plots and artificial restoration of grassland in sandy land of Ordos were studied. The humic acid in steppe soil was isolated and extracted. The content changes of different functional groups of soil Hu Min acid in the course of soil degradation and restoration in desert steppe were analyzed by elemental analysis and nuclear magnetic resonance (NMR). The structural characteristics and differences of HA were studied by factor analysis. The results showed that HA carbon skeleton was similar in different degradation and restoration stages, but the content of various carbon atoms (functional groups) was different. Aromatic and aliphatic structures play an important role in the acid structure of Hu Min. In the degradation stage, the aromatic carbon and carbohydrate of soil HA decrease, and the degree of oxidation of soil HA increases. The content of aromatic carbon increased, the content of carbohydrates increased and the degree of hydrophobicity decreased slightly in the recovery stage. In the stage of soil degradation and restoration, the most important part of the structural changes was aromatic carbon, which replaced the fatty carbon structure. Secondly, carboxyl and ester carbon and unsubstituted fatty carbon structure. Vegetation restoration has an important influence on the changes of humic acid structure. The aromatization degree and compound degree of HA structure in Stipa bungeana area and Artemisia Bungei oil area are higher. The acidity of soil Hu Min is relatively high, the degree of aromatization and the degree of compounding are still low in the fenced area. Therefore, the change of the acid structure characteristics of soil Hu Min can reflect the degree of grassland soil degradation. Further reveal the mechanism of grassland soil degradation.
【作者单位】：中国农业大学资源与环境学院;沈阳农业大学农学院;
【基金】：the planning subject of“the twelfth five-year plan”in national science and technology for the rural development in China(2012BAD14B01-1)
【分类号】：S812.2

【相似文献】