Abstract Molecular assessment of the origin and transformation processes of soil organic matter (SOM) was carried out based on information obtained from 13C NMR and analytical pyrolysis of humic acids (HAs) in soils from wine-growing regions in Tenerife (Canary Islands, Spain). Principal component analysis, using as variables pyrolysis products, shows different soil groups defined by the molecular assemblages released from the corresponding HAs, characterized by the predominance of: i) plant biomacromolecules (lignin) in soils on pumice substrate, ii) heterocyclic N-compounds and methoxyl-lacking aromatic structures, iii) a substantial domain of alkyl compounds in cultivated soils with active C turnover and finally, iv) polysaccharide and protein-derived compounds in soils developed on amorphous gels. The proportions of the pyrolytic compounds from soil HAs were represented by an upgraded graphical-statistical method (3D Van Krevelen plot) that was used to compare the major SOM structural domains in the different soils. The above results coincide with those suggested by the 13C NMR analysis, and were associated to two groups of local land management practices, in terms of their intensity respectively favoring either the transformation of plant-inherited macromolecular precursors from vascular plants, or the humification of aliphatic precursors in the presence of specific mineralogical substrates controlling microbial degradation and humification processes.

中文翻译：

---

农业火山土壤中腐植酸热解特征反映的土壤碳稳定途径

摘要 基于从特内里费岛（西班牙加那利群岛）葡萄种植区土壤中腐殖酸 (HAs) 的 13C NMR 和分析热解获得的信息，对土壤有机质 (SOM) 的起源和转化过程进行了分子评估。 . 使用作为变量的热解产物的主成分分析显示了由相应 HA 释放的分子组合定义的不同土壤组，其特征在于：i) 浮石基质土壤中的植物生物大分子（木质素），ii) 杂环氮化合物和缺乏甲氧基的芳香结构，iii) 栽培土壤中具有活性 C 转换的大量烷基化合物，最后，iv) 在无定形凝胶上开发的土壤中的多糖和蛋白质衍生化合物。来自土壤 HA 的热解化合物的比例由升级的图形统计方法（3D Van Krevelen 图）表示，该方法用于比较不同土壤中的主要 SOM 结构域。上述结果与 13C NMR 分析结果一致，并与两组当地的土地管理实践有关，在强度方面分别有利于维管植物的植物遗传大分子前体的转化，或脂肪族植物的腐殖化。在控制微生物降解和腐殖化过程的特定矿物底物存在下的前体。