Soil-Easily Extractable Glomalin: An Innovative Approach to Deciphering Its Molecular Composition under the Influence of Seasonality, Vegetation Cover, and Wildfire

Easily extractable glomalin (EEG) is a fraction of soil organic matter thought to contain mainly glomalin-related soil glycoproteins produced by mycorrhizal fungi. The EEG has an impact on various soil ecological functions, primarily related to soil aggregation formation and stability as well as wat...

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Detalles Bibliográficos
Autores: San-Emeterioi, Layla M., Lozano, Elena, Arcenegui, Victoria, Mataix-Solera, Jorge, Jimenez-Morillo, Nicasio T., González Pérez, Jose A.
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universidad Miguel Hernández de Elche
Repositorio:REDIUMH. Depósito Digital de la UMH
OAI Identifier:oai:dspace.umh.es:11000/37769
Acceso en línea:https://hdl.handle.net/11000/37769
Access Level:acceso abierto
Palabra clave:soil organic matter
glomalin-related soil protein
analytical pyrolysis
wildfire
chemometrics
CDU::5 - Ciencias puras y naturales
Descripción
Sumario:Easily extractable glomalin (EEG) is a fraction of soil organic matter thought to contain mainly glomalin-related soil glycoproteins produced by mycorrhizal fungi. The EEG has an impact on various soil ecological functions, primarily related to soil aggregation formation and stability as well as water repellence. Here, analytical pyrolysis−gas chromatography/mass spectrometry (PyGC/MS) was used for studying the molecular composition of soil EEG, and a detailed description of the chemical composition is reported. Samples extracted from Mediterranean soils under different vegetation covers (Pinus halepensis and shrubland species, Rosmarinus officinalis, and Brachypodium spp, predominantly), impacted or not by forest fires and collected at different times, were studied. A total of 139 compounds were identified and grouped based on their probable biogenic origin. The EEG chemical composition is dominated by lipids, aromatic compounds, steranes, and hydroaromatics with a remarkable abundance of compounds from plant origin. Significant EEG structural changes can indicate environmental disturbances such as those after a wildfire. The EEG soil organic fraction is found to be a stable and heat-resistant material in nature if soil temperatures remain below 200−250 °C. This study advances the understanding of EEG by providing a detailed molecular characterization and highlighting its role as a stable, heat-resistant component of soil organic matter in Mediterranean ecosystems. The main findings indicate that while EEG is structurally resilient and mostly originates from plant material, its composition is more similar to that of humic acids than to that of glycoproteins.